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CS3099 2006 Group 5 - Computer Science Blogs

1. 32 defero T4 Every group member participated in writing documentation with Angus editing submissions and compiling the complete document 5 7 Novel Features In this section we highlight a number of the most interesting features that our system possesses When considering possible solutions for interface design Flash regularly used for animation and games is not a solution that springs to mind However its tight state control coupled with ActionScript allows it to deliver stylish graphics to produce an impressive graphical user interface Connecting securely to our Java based UMS implementation proved difficult however it was achieved using a tomcat server We felt the benefits far outweighed the connectivity issues resulting in a fresh creative implementation unique amongst our peers The teams earliest documentation project plan and specification stated a desire for a loosely coupled highly modular system We feel that this aim has more than been achieved with each team member initially designing their components in isolation testing internally and then integrating at a later stage In order to achieve this a number of techniques were used including factory classes and independent processes The former are used for requests meaning that the UMS and the VSTM interface only need to know one call to the FDC irrespective of the type of request they are making This single call is applicable to all requests ir
2. wait for the end of the transmission Using a while loop for this will simply cause the Flash to crash as does recursion as due to a bottleneck of 256 levels of this solution The solution was to set an interval and then display the results this period had elapsed Such an interval can only be hardwired making it problematic and potentially causing information be cut off if the network and or server are under heavy load The team chose an interval that was successful in displaying all share details during the demonstration while the lab including our server was attacked by our security program The ideal solution to this problem given enough time would be to essentially use the UMS to make the Flash wait This would be achieved by a new state request to the UMS which would not complete until the other requests were finished On reply of this new request we would then display the full results Another issue that was tackled was with sorting data when displayed in the matrix the table showing the results of queries When we request all shares for example the first share to be displayed is placed in the first index of the matrix Data is then taken from this structure and placed in the table in the same order as the array so when a user clicks on the share or row the row number is used to index into the matrix and show that share in detail This solution works until data in the table is sorted for example by sector name Ins
3. creating the database He helped out in other areas where necessary but his experience was most apparent with the successful creation of the database Ewan A number of members had previous experience in designing websites however Ewan s previous experience with Flash and the languages suitability to our task made him a clear choice for interface design During development he built upon his knowledge of action script to develop a clear well designed interface Greg Having worked with Java sockets before and been introduced to Java security in CS2003 Greg was chosen to focus on the User Management System the component which utilised this experience best His work on security led the standards committee to appoint him Security Co ordinator a role which saw him help other groups create certificates and set up their SSL connections We feel that this division of labour enhanced the teams overall productivity and produced a robust developed system This was in part due to our approach to the analysis of group members relative 23 24 25 26 27 strengths as developed by Belbin and use of other management techniques Members of the team took it in turns to attend standards meetings and all major decisions were made as a group Team members freed their time on Wednesday to allow for at least one day of project work a week In practise all team members spent time out with this often at nights and weekends
4. it first has to be considered what data it needed to store AII team members were consulted about what data their modules needed to store access and perform operations on From this it was found that four main tables were needed users stocks transactions and portfolio as the following diagram illustrates username code PK transaction id PK portfolio item id password currency username username fullname timestamp stock stock access level bid buy quantity mid offer exchange sector official code disp name dividend div pay code Figure 17 Database Schema The underlying SQL was based on these diagrams along with the database management engine that has similar data structures into which data is formatted for communication with the database This highlights the benefits of using an object oriented programming language the data structures could be constructed from a number of forms XML Java arrays and URL encoded strings and vice versa Communications with other modules were fluent and effective When our customer Alice wishes to view her portfolio the UMS invokes a method in the Database Manager that looks up her details and then retrieves her portfolio This is formatted as a URL encoded string and returned to the UMS This is done by sending an SQL query to the JDBC Connector with the result being returned as a linked list The JDBC Connector manages mySQL specific parts of the implementat
5. to reformat into URL encoded data to be sent to the user interface The connection to the user account database interface is done via method invocation The UMS calls the methods of the control class when it needs access to the database This takes the form of adding data to the database or retrieving data stored within the database The UMS has no direct access to the data or the user account database itself thereby abstracting away from the idea of a database entirely a design decision that allowed for a more modular structure benefiting the team if problems occurred on a particular component Structure The UMS is built around a switch statement within the statemachine class When a message is received from the user interface the statemachine class is invoked The message from the user interface contains a state number as well as various fields and parameters Depending on the state different fields and parameters will be present in the message from the user interface The statemachine reads the state from the input and then takes appropriate action for example when in the login state the data sent from the user interface also contains a username and password The username and password are forwarded to the database control class and the return value of this call is an integer that is returned to the user interface The user interface interprets this value to decide what action to take next The UMS was created without any persi
6. Component 2 1 2 2 2 Web Interface The user interface should be viewable on a graphical web browser which has a flash plug in installed The interface will be created on a Windows XP computer but should be tested on the Linux distribution installed in Labs at the time of the acceptance test The focus of this module is on providing a reliable easy to understand interface that can accurately display and interpret the information created in other areas of the system It should show a dynamic representation of data on the fly This module is one of the key elements of the system as the presentation of stock data is vitally important in its understanding 67 un defero 74 Section 8 1 in the appendix shows mock up drawings of a possible user interface 2 2 8 Accounts This like 2 1 4 encompasses the implementation of the user accounts database and the functions required to parse data between it and the User Management System 2 2 1 The database needs to store user details username password access level etc and their portfolio data The latter will need to include references to any company shares stored in the share database 2 1 4 We also plan to store transaction histories here in order to be able display more relevant information to users 3 Communications 3 1 Group Meetings During term time the group intends to meet a minimum of one afternoon a week for project work The actual time spent in this activity is d
7. In compliance with the standards meeting ruling on this these fractions are decimalised correct to five decimal points This is done immediately prior to the data being entered into the database Group control of sectors adds another factor of complexity to the update operation as the feed can only be used for sectors which the group controls shares allocated to other groups must be obtained through the VSTM Updating from Other Groups To abstract the distributed nature of the stock information from the UMS side of the system the team had to create a system for compiling the results of what amounted to requests to a number of other groups Having explored the problem a number of possible solutions were found 1 Every time a request is made route this to all 5 groups including our own request handler N ON o o fe Pd and combine what results are received Request Co ordinate Processor Search Compile Results Results S 2 Every time a request is made get the results solely from our own database This assumes that Figure 11 Proposed Query Request Structure i we attempt to update our database as often as is reasonably necessary Request Processor Seach DIE Figure 12 Proposed Query Request Structure ii y While the first solution potentially gives up to date data it suffers if not all groups are operating and so l
8. This ensured that we learnt a lot about how to defeat the attacks e We developed a strong parser which could the various types of attack shown above without crashing the system e We developed methods of defending against system resources being used up by the creation of multiple threads and the starvation of IP addresses by such a large amount of incoming connections These are documented in the security section page 29 7 Evaluation The section provides a critical evaluation of the teams work based on targets set in the project specification and the final state of the system 38 defero 74 7 1 Project Evaluation We assessed our work on several e Deadlines and hand in dates o Were the deadlines set by the module co ordinator met e Personal goals o Were the teams objectives met e System requirements o The team drew up functional and non functional requirements did the implemented system fulfil these requirements e Standards committee requirements o Did the team adhere to all of the standards drawn up by the standards committee The system was tested in a variety of ways the majority internal testing within the group Other than this testing took place during TUP s and the final integration test attempting functionality with the other groups On an individual component level the components were tested using unit level testing by the developers and then an inter component test would be conducted to
9. User Centred Systems Design Lauesen S 2005 User Interface Design Addison Wesley Burke E 2001 Java and XSLT O Reilly Mangano S 2002 XSLT Cookbook O Reilly Adam Smith 1776 The Wealth of Nations P17 Belbin R M 1981 Management Teams Why They Succeed or Fail London Heinemann Belbin R M 1993 Team roles at work Oxford Butterworth Heinemann Kanter R M 1994 Collaborative Advantage The Art of Alliances Berkun S 2005 The Art of Project Management O Reilly Argyris C 1976 Increasing Leadership Effectiveness John Wiley and Sons Ltd http nds dcs st and ac uk pic details php pic file posters ddos pic info http en wikipedia org wiki DDoS Muck T 2003 Flash Remoting The Definitive Guide O Reilly http www macromedia com software flashremoting Sommerville I 2004 Software Engineering 7 Pearson Addison Wesley 50 defero 74 10 Appendices 10 1 Maintenance The system was designed to be loosely coupled and easily modifiable an aim that was adhered to throughout implementation This along with the following documentation makes the system highly maintainable This section is further split up by system component with each subsection explaining how maintenance of that component should be carried out For details on the purpose of each component please refer to the project details section on page 10 This is a technical document Requirements Ja
10. analysis of the requirements we feel that we have fulfilled our aims and created a successful system that users would benefit from using This is due our creating a solid plan and sticking to the design drawn up We found the modular structure we followed enabled us to create a system that came together well and that was easily expandable We played to our individual strengths in regards to assignment of tasks and distribution of sections Our team fit well into the spiral development model chosen and the use of CVS and our project space for the constant creation of iterations meant that all separate modules were developed in parallel and functioned together as a whole Constant contact with our supervisor kept us up date with progress solidifying in our own minds the status of the project and leading everyone in the team to put aside a set time each week for development work as well as committing extra work when necessary We handled the varying nature of the customers needs by making sure to keep in mind as many possible paths project development as possible and this wide scope coupled with the adventurous decision on the interface design meant we could cater for a variety of possible challenges whilst still allowing our own creativity come through With any project there will be problems that need to be overcome but we feel we handled the emerging challenges well and developed dynamic solutions based on our communications models that enab
11. be contacted via the module co ordinator out with these meetings 68 defero 74 4 Standards 4 1 Header Standards Given that code written by one group member will often be reviewed or modified by another we feel that it is essentially to create a standard for comments within code Class File Header Class Name Author Name Author e mail address Group Name Number Date of Creation See also field Summary of Class Functionality Example Title FeedParser Author Angus Macdonald adm15 Group 5 Created on 29 11 05 See Other related documents This parses stock data from the feed provided and presents it in a format that the financial data centre can interpret a DOM tree In areas where JavaDoc can be appropriately used we will endeavour to utilize this Specific functions or methods within the class should be commented with a summary of functionality and comments on parameters and return values 4 2 Inter Group Communication Standards This section partially deals with decisions already made in standards meetings as described in 3 3 The groups have agreed to use TCP sockets as a means of communicating between groups along with the SHEEP protocol for error handling http en wikipedia org wiki Standard_for Handling of Exception Error Protocol_ 28SHEEP 29 69 defero 74 5 Testing 5 Testing Strategies Software testing is a vital part of the software dev
12. development 16 defero T4 1 Consistency Colours the main menu text style and screen layout are consistent through the states 2 Offer Informative Feedback Buy and sell requests display a message whether or not the request was successful 3 Reduce Short Term Memory Load The main menu has only five menu items at the low end of the 7 2 band used as guide to the number of items a user should deal with at a time Additionally when a confirm window appears the back and forward buttons temporary disappear to reduce the number of buttons on the entire page further reducing confusion 4 Allow Reversal of Actions when a share is selected in the buy or sell screen a back button exists to return to the previous page Additionally when the confirm window appears the user can close this window by clicking the top right x or by the cancel button 18 19 Additional design principles used included 1 Colour association Red was used to cancel things and logouts whereas green was used for forwarding actions 2 Quick logout the logout button is always present in the main menu Communication Communication between the interface and the rest of the system is achieved through a Tomcat server The Flash is embedded in html which is viewed in a secure HTTP environment This ensures that data passed between Flash and Tomcat is secure Data is sent by the post method to the tomcat server URL which then forwards th
13. exception though we found that most problems that cause errors merely caused an exception in a given thread and could not cause the entire system to crash Data and transaction histories will be logged Yes Our system used dual logging to corroborate the details of transactions This ensures that if the system crashes or a discrepancy occurs that the information will be output in a hard copy and in the database history so that the origin of the discrepancy is for more easily locatable All transactions were logged in the database and also as xml output by the FDC Historical data is logged by the database for use with queries within the system Efficiency User event response time will be less than 2 seconds assuming normal load conditions on the host server Partially Whilst the system does respond in less than two seconds to user actions under normal load conditions within the VSTM at the project demo the query to return all shares took some time to be returned This is mainly because we had to wait for the other groups to process our request and reply All user events pertaining to our own system were handled within the two second time frame Action Approximate Response time Loading flash 1s with ADSL Login 0 35 Portfolio 12s Sell ls Logout 0 5 s View all shares 4 s Co operation The system will implement all standards agreed to by the standards committee Yes We succes
14. have any comments on the design of the interface or suggestions for improvements please state them here Name Diii Camo Signature Compt CS3099 Team 5 Stock stem Please answer the following questions circle where applicable Were you able to view your portfolio without reference to the documentation no Were you able to buy companies shares without reference to the documentation no Were you able to sell shares from your portfolio without reference to the o documentation Did you find it difficult to use any of the features of the interface without having yes fi to refer to the docurnentation Were you able to use other interface functionality to the desired effect with use of o documentation provided Were you happy with the load times of the system on queries nol If no please explain here If you have any comments on the design of the interface or suggestions for improvements please state them here Ve MANE ndor faca Name John nacLach la Signature th Peur 93 If you have any comments i rang cde tl on the design of the interface or suggestions for improvements 94 I ru 3 documentation name Michael Timmons seem Ml A J limiares D amp 0 ALL Bh aandaa C83099 Team 5 Stock trading system Please answer the following questions circle where applicable Were you able to view your portfolio
15. is just as simple This is achieved by adding a new state or frame with additional ActionScript added to this and graphical elements placed in their relevant layers To set up new communication with the User Management System a new state code is required along with the relevant details of the functionality the User Management System must be updated to cater for these changes User Management System Java The UMS is simple to maintain due to the simple design This was a conscious design decision since we planned to have to add lots of features towards the end of the development once the data routing between the separate components was set up The servlet would not need updating via maintenance unless the URL encoding communication interchange format was altered this would require a different implementation of the wrapper class inside the servlet java class The session timeout can be altered by adjusting the web xml file within the web app This is a simple modification In order to add extra functionality to the UMS simply add a new state code and a new case within the switch statement This will provide the UMS with a new state New parameters to be received from the user interface can be added to the InputParser class There are comments inside the source to tell the programmer where to update in case of necessary maintenance It would be required that the necessary functionality be provided within the FDC database cont
16. over the VSTM 4 2 1 3 The user will be able to view their portfolio 4 2 1 4 The user will be able view expanded details of their shares including but not limited to Code Currency Timestamp Mid price Bid price Offer price 60 defero 74 4 2 1 5 The user will able to query stock details listed in 4 2 1 4 within the system and the wider VSTM 4 2 1 6 The system will have a graphical user interface This will Relay all aforementioned data to the user Inform the user of any errors should they occur 4 2 1 7 The system should support multiple users 4 2 2 Co operation 5 4 2 2 1 The system will be able to transfer stock data including but not limited to 4 2 1 4 bullet list over the VSTM Terminology 5 Project Terminology System A collection of components organized to accomplish a specific function or set of functions In our case this includes all the software our group writes User A person that uses the system Virtual Stock Trading Marketplace VSTM This is an abstract notion representing the network of group project systems over which users will trade 5 2 Domain Terminology Stock Market Where stocks and shares are bought and sold a market in which the shares of corporations are traded Stocks Shares A stock also referred to as a share is commonly a share of ownership in a corporation Code Share code The 1 5 letter abbreviated a company uses for listing on th
17. page the user often having to swap between pages to find what they require This highlighted the importance of layout in displaying content Little user interaction is required in the form of data entry consequently the layout of the user interface is a driving factor for an intuitive system However the TSimLite system suffered from similar problems leading us to conclude that neither system is ideal The scope of the project limits the depth of our program from areas such as dynamic graphing and advanced transaction types making it easier to fit relevant information into one page defero 74 5 Project Details The system delivered by Defero manages to meet the majority of the system requirements this section explains the methods used to achieve these goals Early in the design stage the team decided to focus on a number of core components as explained in Interim Report appendix page 76 identified as crucial to the operation of the system These core components were e Feed Parser parsing of the data feed provided e Basic Request Handling enabling the system to communicate with others at inter group tests e Basic User Interface a command line interface allowing us to request from ourselves and other groups Implementation of these components was prioritised over others ensuring a solid foundation for later work Before designing specific components of the system the group agreed on the global system
18. regulations of the University Library We also give permission for the title and abstract to be published and for copies of the report to be made and supplied at cost to any bona fide library or research worker and to be made available on the World Wide Web We retain the copyright in this work Gregory Bigwood gjb4 Duncan Fowler df15 Angus Macdonald adm15 Ewan Summers es54 defero Contents 1 j 2 2 I Tore M 2 3 jUnn 5 3 1 ANG EDI EUER 5 3 2 Theas keon EE 5 3 3 AMIS OL REPOT E 6 4 Context SULVOY os oo Sevecdacedsceectestsoscesdaacscosssosssueeessaesseoussnicessecessasasvocscosssessossssecseesesabessonsesnes 8 5 Project cci ce 10 5 1 Development hs EUR 11 5 2 Standards Meeting E eioi a R EAEE A EE RE RER EE 13 2 9 Ib spagbs re 14 5 4 MDOSI PI OVERVIEW EUER 14 RN EE Sic n 15 5 4 2 User Management System UMS sese een rennen nnne 19 34 3 Pimaneral Data Centre eee rr etm e PEE oa Ta r EE Rer ene Fere e aee EEE EE EE 21 34A Databas MEC 26 RU RNMEME I de eie EEE EE AEE E E EE E RETE A EEE EE EER 28 5 3 Nang AM E E EEE EPEE A EEEE EEEE E TEE E EEE EEEE E E e E TEE ne EE EEEE 29 5 6 Alloc
19. secondary preferred and tertiary optional extras goals to prioritize our specification and aid our design 2 1 Core Aim To create a system that simulates buying and selling shares over a virtual stock trading marketplace VSTM This is an abstract notion representing the network of group project systems over which users will trade Users will have their own accounts allowing them to view their details and details of other shares 2 2 Portfolio Management System We view a portfolio as a collection of investments held by our user s 2 2 1 Primary To create a system which allows a user to buy view and sell shares The user should be able to query stock details from within our system and the wider VSTM Graphical user interface for the end user 2 2 2 Secondary System should be able to support multiple users with individual logins They should be able to have personalised portfolios 2 2 3 Tertiary The system should support concurrent connection oriented requests The system should support concomitant users logged in 57 defero 74 2 3 Co Operation 5 3 2 Primary To exchange stock information with other groups Implement all standards agreed to by standards committee 5 3 3 Secondary To be able to buy and sell shares where there are a limited number of shares available over the whole VSTM 5 3 4 Tertiary The number of shares within the VSTM remains constant 3 Context Survey I
20. semester This section summarises the achievements of the project discussing aspects of particular interest and explaining implementation details deemed interesting The teams project specification identified the following use case 14 defero T4 The user will want to be able to login to the system to trade shares view their portfolio and to query share information The following example gives an idea of how a user might wish to use the system The user wants to check how their portfolio is performing They login to their account and view a list of shares they own with relevant details Wanting to know more about a particular share they choose to view expanded information on it Having looked at the data shown they decide they want to sell all their shares in the given company Having sold these shares the user wishes to buy some more in a different company They query the shares available over the VSTM to find one of relevant interest to them Later having found a share they wish to purchase they are able to buy the share This is then added to their portfolio This will be used as an example throughout this section highlighting the functionality and purpose of each module used Our fictional user will be called Alice 5 4 1 User Interface The Flash MX developing environment is primarily designed towards movie design or animation It includes the ActionScript scripting language Underlying Design As ment
21. to cause extra load on their system to slow it down as well as creating a large number of threads within their system e Malformed request Creates and transmits a malformed query request invalid XML by leaving out some brackets This is designed to crash a poorly implemented parser e Incorrect order Sends a message containing xml tags incorrectly nested in order to crash a poorly implemented parser e Junk data This sent a string saying connection error to the group rather than XML e Extra New lines A number of groups had problems parsing incoming messages if they contained new line characters This was designed to see if they could be handled e Infinite connection This connected to the target and didn t send a message This meant that if they didn t have socket timeout that the connection would permanently remain open and a large number of these connections would cause the memory to fill up or the ports to be fully allocated e ll Formatted Trade Request Try to buy some shares using a badly formatted trade request e Slowdown Used to demonstrate the superiority of our web based system compared to other user interfaces that were slower and based unnecessary strain on users systems This attack spawned a very small C program that allocated as much system memory as possible It was allowed on a machine running the zombie program with the intention of disrupting the demonstration of anyone using the computer When first tested so
22. without reference ta the documentation no Were you able to buy a companies shares without reference to the documentation no Were you able to sell shares from your portfolio without reference to the Geno documentation Did you find it difficult to use any of the features of the interface without having _ yes 91 to refer to the documentation Were you able to use other interface functionality to the desired effect with use of no documentation provided Were you happy with the load times of the system on queries Pno If no please explain here If you have any comments on the design of the interface or suggestions for improvements please state them here 95 10 9 Sector Allocation Group 1 Asset managers Banks Building materials Food processors Inv tst international Inv tst geog speclsts Med equip supplies Media agencies Pharmaceuticals Shipping and ports Group 2 Airlines airports Business support Chems advanced mats House building Life assurance Other construction Real estate dev Tobacco Water Group 3 Aerospace Consumer finance Distillers vintners Inv tst european Investment banks Investment trust uk Leisure equipment Publishing printing Transaction payroll Group 4 Auto parts Computer services Electricity Electronic equipment Insurance non life Leisure facilities Other mining Restaurants and pubs Retailers e commerce Group 5 Biotechnology Brewers Builders m
23. 80208 Fri 240302 AN Mor 060003 Fr260303 GB Mor 100808 F Moe 100603 Moe 280208 Moe D amp 0203 Moe 180403 T Mor 100803 Mor 1004502 14 0403 AM DF ES GB Wed 301105 Ths 250506 GB Mor 150503 Fr 106508 AMDEES GB Wad 307105 The 250506 AN Wed 301105 The 250595 DF Wed saves TRIES ES Milestone Bb Deadine AM Angus Macdonald GB Gregory Bigwood ES Ewan Summers DF Duncan Fowler As the project report includes other documents created throughout the project this is listed as starting at once 7 2 Risk Identification Risk Probability Tolerability Agreed Action Loss of team Low Low Redistribution of workload evenly loss of 72 defern member functionality Dramatic increase in High Low Identify main goals attempt to achieve them scope prioritise goals allow more time for deadline due to inadequate time allowances Personal factors Med High Redistribution of tasks Change in High Med Use spiral model flexible to have prototypes requirements to show customer and maintain communication In event of change the previous cycle can be visited External factors dept Low Catastrophic Attempt best case solution extend deadlines is problems possible System security flaw Medium Low Pool all resources to combat flaw 73 c defern 8 Project Plan Appendix 8 1 Graphical
24. Diagram 2 1 1 Financial Data Centre This is the core of the stock trading simulation Unlike other modules described here its size requires it to be sub divided into sub modules These are described here Interfaces The data centre should be loosely coupled with the rest of the program We aim to achieve this by having two interfaces one for incoming data and one for outgoing data Financial Data Processing The data provided from the feed doesn t contain all the information users will need for their portfolio The aim of this sub module is to provide this extra information for example commission by processing the available data Another use of this module would be the calculation of indices for given shares the 100 most valuable shares in the London Stock Exchange would be in the FTSE 100 Share prices can be used to calculate overall market performance and other indicators of this nature Logging To provide means of testing and auditing of market and user data a logging function is needed This should simply log the actions of the module such as the selling of shares and save these logs to an external file 66 defero 74 Updating The database needs to be updated periodically with the latest share prices The updateDB module controls the timing of these updates and ensures that historical data is stored and accessible Its design should allow the timing of these updates to be altered as no information has ye
25. EST PHASES INTEGRA TIONAND N V AccEPT V TEST IMPLEMEN V ANCE TEST TATION 3 Figure 6 Spiral Model Diagram The main difference between the spiral model and other software process models is the explicit L 14 recognition of risk in the spiral mode While there were fewer changes to the original specification than anticipated the spiral model was integral to our success in creating operational prototypes for each inter group test Development on the first prototype focussed on the FDC as this functionality was required for the first TUP in week six of the first semester Following this test the FDC was developed further adding functionality and improving reliability of the feed parser Work on the UMS began in earnest prior to the start of the second semester however this component was not used in any TUP s until week 8 Meanwhile the request handling component of the FDC was re written improving robustness and adding additional functionality needed for future TUP s Design evolved with each prototype ensuring a solid foundation for further development 1 1 r Testing of Universal Progress the name given inter group tests 12 5 2 Standards Meetings All groups involved in the project sent a representative to weekly standards meetings These meetings were designed to create agreement on protocols for communication between groups Communication out with meetings was possible via email cs3099 stu d
26. S in buy requests 25 Interfaces with Databases ee Deed Ute P ERE RERO NEIN eee 26 Database Schema s RUNE OE E E SIR EIRISC WEE ME 27 Data flow through the logging package eeeeeeeneeneeneneneeeenenn 28 Flow of control within attack programs eseeeeeeeeeeeeeeeen nennen eene 38 defero 74 3 Introduction This report represents the body of work completed as part of the software team project and combines 1 2 3 previously published documents with expanded detail and conclusions 3 1 The Team We group five chose to name ourselves Defero Latin for communication as we feel this aptly conveys the aims of the project and the attributes that are needed for a successful team 3 2 The Task Stock exchanges exist to provide the facilities of a marketplace where potential investors can put their money to work by purchasing securities and those who already own securities can equally freely and speedily turn them into cash P The customer wanted a simulation of trading on a stock market to be created He appointed five teams to each create independent simulation systems which co operate to form a virtual stock trading marketplace VSTM We envisage this as a network of systems upon which simulated stocks may be traded Each team is responsible for one of these systems and acts as a market maker that is a body that maintains and trades in shares allocated to it by
27. Sir Stephen Killik E Couchman amp Co Ltd Bulls Bears and Microcomputers Programming for Successful Investment G T Childs Sigma http finesse ac uk tags finesse html 59 m defero http game marketwatch com http www tradingsimulation com tsimlite 4 Requirements Specification 5 4 1 Non functional Requirements 5 4 4 Reliability 4 1 1 4 The user will be able to login within the JH Lab John Honey Building The system will have a mean time to failure of greater than one hour 4 1 2 Usability 4 1 2 1 Auser new to the system will be able to use the systems core functionality viewing portfolio buying selling shares querying without reference to documentation 4 1 2 2 A user new to the system will be able to use the remaining percentage from 4 1 2 1 with documentation provided 4 13 Robustness 4 1 3 1 The system will be able to restart in less than 10 seconds upon any fatal exceptions 4 1 3 2 Data and transaction histories will be logged 4 1 4 Efficiency 4 1 4 1 User event response time will be less than 2 seconds assuming normal load conditions on the host server 4 1 5 Co operation 4 1 5 1 The system will implement all standards agreed to by the standards committee 5 4 2 Functional Requirements 4 2 1 Portfolio Management System 4 2 1 1 The user will be able to buy shares from any group over the VSTM 4 2 1 2 The user will be able to sell shares to the market maker
28. User Interface Diagrams These diagrams are indicative of the appearance of the interface Not all planned screens are shown here these screens show views for the stock trader Login page Portfolio page Query page Sell page Buy page 74 defern 8 2 Use Case Model Market owner view trader portfolio query stock odify workings o system program strategy Stock analyst Stock trader Developer Use case model for system visualised in section 2 8 3 Sequence Diagram display portfolio info click sell shares pass share info notify shares mark parsed portfolio info receive confirmatio update transaction history display protfolio info Sequence diagram for Stock Trading Using their Portfolio 75 defern 10 4 Interim Report 76 defero x This report aims to illustrate the progress made by the group since we outlined our schedule in the project plan Progress since submitting the report was initially slow in part due to the increased focus placed on exam revision The group spent some time researching various technologies needed to achieve a reliable and secure connection between our flash interface and Java implementation In addition we looked at more imaginative methods of parsing as the current Xerces implementation is computationally expensive While we are reluctant to alter fully functional modules at this stag
29. able to login within the JH Lab John Honey Building Yes It is possible for users to login within the JH lab and also from any location that is able to access our web server via the school network or internet The system will have a mean time to failure of greater than one hour Yes Throughout development the system was tested over extended periods of time and remained functional for well over the one hour requirement During the project demonstration the system was active for over an hour without failure The original one hour requirement was intended to mirror the time frame of the project demonstration Usability A user new to the system will be able to use the systems core functionality viewing portfolio buying selling shares querying without reference to documentation Yes We believe so since buttons are labelled and messages are given to the user This has been confirmed by our user survey carried out once the interface was functional All surveys returned are shown in the appendix on page 92 A user new to the system will be able to use the remaining percentage from 4 1 2 1 with documentation provided Yes As above our user survey appeared to confirm that this objective was achieved Robustness The system will be able to restart in less than 10 seconds upon any fatal exceptions Yes 42 defero T4 It is possible to restart the system in less than 10 seconds upon a fatal
30. are the choice bar would be modified and a new case in a switch statement would need to be added e Indication of how well the share is doing extra variables sent to Flash to be displayed to the user In addition to these the team would like to add a number of other features to the user interface Due to the structure of the code base this is a relatively simple task as all that needs to be created is a new state code and another case statement in the UMS This makes maintenance easier for the user interface Some considerations for improvements were e Tool tips e Graphing e More detailed stock information e Regular calculations displayed For example how many shares the user owns in all companies Database Java mySQL The database itself is efficient scalable and dependable and is unlikely to require major changes to adapt to having to store additional data To extend the database functionality by adding the ability to store previous stock prices data warehousing techniques would need to be used Changes to stock prices could be logged on change and snapshots of stock prices could be taken at intervals such as every hour If Java 1 5 had been available on the lab machines used for developing the system some of its features could have been used to improve the implementation of the JDBCConnector Variable numbers of arguments for functions and generic data types would have made passing data from the DatabaseManag
31. ares compared to this balance a buy request made and if all of this is successful then the UMS can return to the user interface that Alice s purchase was successful 5 4 3 Financial Data Centre This section describes the operation of the financial data centre FDC incorporating request processing and the reading of the data feed These functions are both called through a central start up class so we will observe this first System Start up systemStartup SystemStartup This class is responsible for starting up the entire system It starts server threads for every distinct division of the system Included in this are the two core features of the FDC beginning with the data update package Data Update Package fdc dataUpdate This package deals solely with updates to the database In the first prototypes created the package also contained a makeshift database a linked list consisting of share objects in Java For the purposes of this documentation the prototype using a linked list database will be called the original implementation and further prototypes identified as latter implementations 21 defero T4 This package is run from the UpdateServer class Once this has been started the class periodically updates information stored in the database by running the relevant method in the feed parser and requesting from other groups Feed Parser fdc dataUpdate feedParser The data feed was provided by the custom
32. arge chunks of data could be omitted from results not an acceptable situation Updating stock information from other groups frequently every minute reduces the problem of old stock data while timestamps inform the user if this is the case 23 un defero 74 The group decided that the second option was the better of the two We felt that omitting certain stock information could potentially be detrimental to a user and this situation should not occur Where historic stock information is viewed the user is informed through the timestamp field As this issue only affects queries and not transactions this decision doesn t affect the user financially To implement this solution the team had to rewrite our Update Server in order to request from other groups periodically The team encountered difficulties when a buffer problem meant that large parts of requests were being truncated before completion To solve this problem the following method of multiple requests was created Query Shares gt A lt queryReply gt 1 Search for all shares 2 If the queryReply end tag is not received remove all characters after lt mi the last valid share data i e remove everything after the last lt share gt lt queryReply gt 3 Find the code for the last share n lt code gt MNR lt code gt received In the example shown this is MNR lt share gt 4 Search for all shares
33. at Currently code is available for adding data into the database from XML files and Java Arrays and code is available to output data as XML files Java Arrays and URL encoded Strings The framework provided for this code makes adding support for other data formats a straightforward task 54 defern 10 2 Project Specification 55 defern 74 Problem Definition 1 1 Introduction Stock exchanges exist to provide the facilities of a marketplace where potential investors can put their money to work by purchasing securities and those who already own securities can equally freely and speedily turn them into cash The customer would like a simulation of trading on a stock market to be created They have appointed five teams to each create independent simulation systems which can co operate to form a virtual stock trading marketplace VSTM This is a network of systems upon which simulated stocks can be traded Each group is responsible for one of these systems The stock market is a complex environment that new users could find difficult to understand Inexperienced users may be hesitant to deal with real money when they don t feel comfortable with the market procedure e The customer shall provide a data feed containing historical stock information hence the groups will be trading on a liquid market This should be seen as ability to buy or sell a stock quickly and in large volume without substantial
34. ation OF TASKS 5er mr eterne Peto teet ee EEr EE URS EEEE e E E A TERR na PEEKE EETAS 31 5 7 oda lc ESEAS 33 6 ID T 34 6 1 ecu M 34 6 2 TUP Testing iude eur RU OR E es DII MINORE 35 6 3 Robustness Testing 31 sienne DIR HONO ORI E Sie neni 35 7 Evaluation 38 7 1 Project Eyaluation 5 sie aD nd ed eR REN ORE E 39 7 2 Integration Testi ue Eee ERRORI OO RIS ORE UE Bee NER RU 39 7 3 ec Sorrisi a eles E Rios iis EG VE SE ee Re ee 40 7 4 Requiremenits e retener eme A we BE a lee Ye DRE ee EN HUS SERRE NA ERE ERE THERE 42 7 5 Design DecisiOfis c nire o A eee A RA IS DERE EU EE ee 44 7 6 Comparison With Other Groups sesseseeseeeeeeeneenren eene nenne nennen trennen renes 45 dun Comparison With the Public Domain eese nennen nennen 45 8 Unn 47 8 1 Achievem ents of Teatri eerie erepti ee ene R e XR EE RE P TREES ERR EY PER UU REY EER E ERE ERE NH n 47 8 2 Future Direction Of WOtKk i eto ete te cte PER eR E Ee PEN Yr Gee NER eere exe ce Esa ce VETE 48 User Management System UMS sess nennen trennen ren rennen ieS 48 ser Interface Flash pena demittere unir 49 Database Java mySQL isis eet etie cbe Ene Qe RUNE FR FER Y cR PESE e R
35. be shown e Ifa timeout occurs you will be taken to this screen A timeout after five minutes Portfolio Your shares will be displayed in a scrollable table with the following information Code This is a word with maximum length of 4 letters that represents the share Mid price This is a rough average of the bid price and the offer price Bid price This is the highest price that the market maker is willing to pay for a specific security Offer This is the lowest price acceptable to a market maker for a specific security Held This is the number of shares you hold for a particular share Available This is the number of shares available for a particular share Note on available This is not implemented across the share network All shares controlled by the Defero sector will have this value shares controlled by other market makers will have value N A e You can sort this table ascending or descending order by clicking on the Code column e Below the table your balance will be displayed portfolio worth the amount you would earn by selling all the shares in your portfolio the currency and the exchange 80 Main menu The main menu is the set of buttons located at the bottom of the portfolio options buy and sell screens e The options button displays the user options e View portfolio displays the user portfolio details e The Buy shares button allows you to search for and select shares to buy e The Se
36. ceed total memory available on the system Flat file storage provides a simple mechanism for data storage and retrieval however it can lead to slow data access times when the data is being searched upon Using a database management system it is possible to store large amounts of structured data in a way that allows data to be searched very quickly by using a technique known as indexing Like an index in a book the index is a small and can be quickly searched to find the data required User Stock Price Interface Feed Reader Database Trading Server Figure 16 Interfaces with Databases As the above diagram shows many sections of the project require the use of structured data storage These sections are developed in both Java and Action script and communicate using various combinations of XML URL encoded strings and Java function calls To communicate successfully to these different modules it was decided to write the database management engine in Java 26 defero 74 Java is a flexible programming language which has good support for database engines XML parsing and data manipulation MySQL was chosen as the database management system as it is available on the junior honours laboratory server it can be accessed from Java using a JDBC Java Database Connectivity database driver and the team already had experience in using it To design the structure of the database
37. cks the flexibility required for a project where the risk of requirements slippage is high We can assume this as the customer appears to be unsure about the exact nature of the product they want and is vague about exact requirement details The spiral model allows for this kind of evolutionary development whilst maintaining the documentation structure of the waterfall model CUMULATIVE coat PROGRESS 2 lt I j DETERMINE EVALUATE OBJECTIVES ALTERNATIVES ALTERNATIVES IDENTIFY CONSTRAINTS RESOLVE RISKS j P S RISK ANALYSIS RISK ANALYSIS COMMITMENT PARTITION REVIEW SOFTWARE DETAILED PRODUCT DESIGN REQUIREMENTS DESION VALIDATION DESIGN VALIDATION AND VERIFICATION TIONAND N ACCEPT M TEST IMPLEMEN V ANCE TEST Software Engineering A Practitioner s Approach Roger S Pressman McGraw Hill Higher Education 2004 Page 35 Spiral Model Diagram taken from http www stsc hill af mil crosstalk 2001 05 boehm html 63 defero T4 Figure 1 The main difference between the spiral model and other software process models is the explicit recognition of risk in the spiral model 1 3 System Software modules From a high level perspective the system can be divided into two components the Market Maker component and the user management component The Market maker component consists of the following modules the database module
38. connection oriented requests Our system supports many concurrent connection orientated requests from one or more different parties This number is limited only by the hardware upon which the software runs and network capacity The system should support concomitant users logged in It is possible for many users to be logged in using the system at the same time from a variety of locations ranging from a single machine to any machine that can access our web server This is all done securely via https Co Operation Primary To exchange stock information with other groups Our system exchanges a variety of information with the other groups including and not limited to the stock information that was provided to all groups by the customer Implement all standards agreed to by standards committee We adhered to and implemented all standards agreed to by the committee Secondary To be able to buy and sell shares where there are a limited number of shares available over the whole VSTM The shares were limited to a maximum quantity of 100000 per share and we are able to trade with these shares over the VSTM 41 defero 74 Tertiary The number of shares within the VSTM remains constant Due to factors out with our control the feed can periodically add new companies to its data making this aim infeasible 7 4 Requirements Non functional Requirements Reliability The user will be
39. cs st andrews ac uk but decisions on standards issues could only be made and verified during the meeting It was agreed that no person could represent his or her group in consecutive meetings Good efficient decision making in these meetings was identified as critical to our teams success As a result the team actively took a lead in decision making presenting several comprehensive proposals The XML schema which defines the format of communication was created and maintained by our team We took note of all schema related issues raised however we were solely responsible for all significant changes All schemas were designed with simplicity in mind to prevent confusion on such a vital area The schema went through several iterations gradually adding functionality with the final version shown in the appendix 7 10 6 Tow types of requests are specified here The first the queryRequest is used to request share details with the latter tradeRequest used to buy and sell shares within the system The format for sending XML was a more divisive issue with our group arguing for the use of TCP over HTTP requests This decision was justified by the success of inter group communication in later TUP s and in the final integration test Groups created a standard list of errors based on the SHEEP system This concept is explained and the codes are listed in the appendix page 89 Following a number of customer meetings it became clear that s
40. ct Specification see page 56 and states whether we were successful in achieving them Portfolio Management System Primary To create a system which allows a user to buy view and sell shares This aim was achieved fully our system successfully allowed users to view share information and to successfully buy and sell these shares within the VSTM The user should be able to query stock details from within our system and the wider VSTM Users can perform various queries on the stock data in order to select the shares that they wish to buy or sell or even just for basic browsing More specific data is also available to the user including all the 40 defero T4 information we were able to access from the feed and also extra information such as the current amount of a particular stock held by our group Graphical user interface for the end user We created a graphical interface that allowed the user to perform the actions specified above and also extra features not laid out in the requirements Functionality within the user interface is described on page 15 Secondary System should be able to support multiple users with individual logins They should be able to have personalised portfolios The Defero system allows for multiple users and each of these users has an individual portfolio that they can buy and remove shares into and out of respectively Tertiary The system should support concurrent
41. documentation no Were you able to buy a companies shares without reference to the documentation no Were you able to sell shares from your portfolio without reference to the no documentation Did you find it difficult to use any of the features of the interface without having lyes to refer to the documentation Were you able to use other interface functionality to the desired effect with use of Kehno documentation provided Were you happy with the load times of the system on queries yeso Ino please explain here whan byth te wew a charts lods If you have any comments on the design of the interface or suggestions for improvements please state them here Name Dewars FeERGISON 92 defer CS3099 Team 5 Stock tradi Please answer the following questions circle where applicable Were you able to view your portfolio without reference to the documentation fyes no Were you able to buy a companies shares without reference to the documentation ey no Were you able to sell shares from your portfolio without reference to the yey nol documentation Did you find it difficult to use any of the features of the interface without having yesAfioJ to refer to the documentation Were you able to use other interface functionality to the desired effect with use of Fesina documentation provided Were you happy with the load times of the system on queries yeso If no please explain here Sansa re dn If you
42. e This feature is especially useful when attacking all groups systems at once Attack types During the year at the TUP tests we would learn about different groups problems and problems we had encountered ourselves constantly updating our parsing to protect against them As an example incorrect XML formatting would cause some groups XML parsers to malfunction and therefore crash their system In every message sent to the other groups we declared out team name to be that of the group we were attacking the idea being that the victim would read the request and return the response to themselves causing extra processing not to mention confusion 36 defero T4 Throughout testing we saw the biggest loophole in the communication protocol as being the lack of security a connection could come from anyone For this reason we suggested that SSL be implemented for inter group communication This meant that only authorized groups could make connections to each other As a result our zombie program had to use an SSL connection and therefore our groups certificate This meant it could be traced back to us if the certificate was examined but as the object of the testing was to point out weaknesses this was not of any importance The following attacks were implemented e Request all Creates an SSL TCP connection to the target and requests all the shares in their system to be returned the connection is then dropped This is intended
43. e initial parsing may in future be altered to a partial XSLT Xalan J implementation Once exams were completed the group took advantage of the inter semester break spending a week implementing the core system These areas identified as critical to the systems operation included the parsing of XML the database and a secure connection between Java and Flash In addition the group created formal plans for the structure of the User Management System and Financial Data Centre introduced in the project plan Progress with XML parsing and the creation of a system update module was relatively unhindered however the creation of a request handling module was restrained by a lack of agreement on inter group standards As a result proposals were drawn up to present to the standards committee at the next meeting The group is currently in charge of all inter group standards as we control the XML schema for communication and are responsible for updating it Group members working on the Flash Java connection made slow progress initially due to difficulties in connecting securely to the interface via Apache Tomcat the servlet handler being used Following further focus on this problem the connection is now secure and fully functional Despite these setbacks we are satisfied with the progress that has been made since November and are confident that our implementation is adaptable enough to cope with further requirements changes These changes
44. e data A listener is set up to act upon data sent from tomcat which has been URL encoded As the reply is placed in another object variables can be accessed using specific notation For example if name 5 amp was sent from tomcat myreturnvars name would give the value 5 ActionScript needs to be told what to take from each LoadVars object To resolve this state codes are sent from the Flash to the UMS and variables are sent by comma separation For example the code of the shares is sent as code firstcode secondcode thirdcode amp The team wrote a method to convert the data from comma separated to an array of strings that could then be indexed into to display or act on the data Design Issues Our initial method of communication was unfortunately unsuitable for sending large amounts of data flash has a fixed buffer size of two thousand we required twenty six thousand but the team iterated on our initial design and found a solution The solution was simple another state was created to request the number of 2000 requests to make Then using a loop we make all the requests using the looping count as an index into an array on the UMS side Each request is then stored in a matrix By making 17 defero T4 use of the function to convert comma separated data to an array we can concatenate the resultant array with the matrix making use of Flash s loose typing system Unfortunately there is no easy way to make Flash
45. e framework reliable and robust code throughout Due to the modular structure of our code it would be easy to add additional functionality to our project in the future 7 7 Comparison With the Public Domain Due to time constraints experience and budget our system cannot compete with commercial or industrial examples of a portfolio management system However the team worked hard to resolve weaknesses seen whilst carrying out our context survey Finesse had various issues displaying data due to the amount of detail that needed to be displayed In this regard our team had relatively few details that need to be displayed however share details were deliberately limited when viewing lists of shares to prevent confusion these details such as offer and bid price are shown later when the user views a particular shares information By doing this we reduced the risk of having to display too many details at any one time If increased detail is required our implementation will be able to support displaying far larger amounts of data 45 defero T4 Similar to Finesse our implementation is viewed through a browser meaning the GUI is platform independent It can also support multitudes of users since each Flash page is instance independent The Virtual Stock Exchange was also researched for this project with the team noticing that although the web based stock trading simulator had advanced features such as graphing it failed to display al
46. e gateway for the user into our system and also into the VSTM although the VSTM is abstracted away from the user interface implementation Data is returned to the user interface in a helpful table format with errors displayed if transactions fail The system should support multiple users Yes There are several account types each with different access privileges There can be multiple users of different types using the system concomitantly Co operation The system will be able to transfer stock data including but not limited to 4 2 1 4 bullet list over the VSTM Yes We can successfully transfer data to the other groups over the VSTM using SSL encrypted TCP connections that provide a robust secure communication data transport layer to our system 7 5 Design Decisions Taking into account the challenges the team encountered during development we feel that our choice of development languages allowed us to provide a robust solution to the customers problem Java provided the ideal framework for the creation of robust object oriented code justified by robustness testing documented on page 35 By using Java libraries coding was focused on functionality and based on a tried and tested core of code The team feel that the choice of Java hastened development by utilising previous experience and allowed for the production of robust code 44 defero 74 MySQL provided everything required for our database implem
47. e query into a Java object simplifying later processing However this is by no means required To methods are required within request classes o public Document start This essentially processes the request This should return a Document object containing the reply If you need to return one of the standard system SHEEP errors simply make a call to the error creation class common types SHEEPErrors o public boolean isSuccess Returns whether the reply was successful or if an error was returned Alter the Frequency of Data Updates To do this the following line must be changed in systemStartup SystemStartup new fdc dataUpdate UpdateServer 2 fdc dataUpdate UpdateServer MINUTE start The second highlighted text MINUTE indicates the time period for updates The following are available SECOND MINUTE HOUR DAY The first highlighted text 2 specifies the frequency of the update For example in the above code example updates are carried out every two minutes Allocate New Sectors Sector allocation is stored within common types SectorAllocation To add new sectors to a specific group s allocation simply add the name of the sector as it is within the feed to the relevant groups String array Each string array is named after the group number for a given group so our sector allocation is in the array five 53 Database Database Interface Java mySQL The data management engine uses abstraction
48. e stock exchange Mid Price The mid point between the bid and offer price quote in the market Buy Price the price at which another party will buy the stock Offer Price The price an investor can buy from the market also called the ask price Data Feed Stock data supplied by the customer Timestamp The time that the stock information was taken from the data feed Portfolio a list of the financial assets held by an individual the user Liquidity ability to buy or sell an asset quickly and in large volume without substantially affecting the asset s price gt IEEE Standard 610 12 61 defern 10 3 Project Plan 62 odefero 1 Document Overview 1 1 Introduction to Problem The customer would like a simulation of trading on a stock market to be created They have appointed five teams to each create independent simulation systems that can co operate to form a virtual stock trading marketplace VSTM This is a network of systems upon which simulated stocks can be traded Each group is responsible for one of these systems Please refer to the project specification for a more comprehensive explanation of the problem 1 2 Development Model We have decided to adopt the spiral model of software development see figure 1 This system best represents the timescale and targets set out by the customer While the major project milestones tend to suit the waterfall model this model of development la
49. e unofficial class integration test on 10 March and we have been working to this end 78 10 5 User Manual The Defero stock trading system allows secure multi user access from anywhere in the world with Internet access Through your Internet browser with a flash player installed you can buy sell and search for shares You can manage your portfolio without ever having to leave your computer Installation Please ensure you have flash player installed in your desired Internet browser Open the Internet browser and enter the following URL and press return enter https 138 251 213 23 20065 defero You will be greeted with the login page If you have a user account setup please refer to the logging in section otherwise please read the accounts section Accounts e To manage your portfolio you must have a valid account If you already have an active account you can skip this section e To setup a new account please contact the system administrator You will be given a username and password which you can then use to access your portfolio e Ifyou wish to change your password you can do so from user options while logged in Logging in e To login please enter your user name into the user name field and your password into the password field 79 defern e Click on the login button to login If login is successful your portfolio will be displayed otherwise a friendly login failure message will
50. eck Share Sector E Process Request Figure 15 Abstraction of VSTM from UMS in buy requests This implementation handles requests from both the VSTM and the UMS with the same interface This is possible as the request processor has three constructors two which handle internal Requests and Buy Requests and another which takes in text requests from the VSTM As the latter diagram illustrates this happens irrespective of the group in control of this sector This control is completely abstracted away from the UMS consequently the User Interface In our example Alice has just requested to view some share details The FDC receives this request from the UMS knowing nothing about Alice As the model updates from other groups periodically this request is automatically handled through our database for the FDC this is a call to the database interface with the result returned as a XML Document object as shown in figure 13 When Alice wants to buy a share she will first search for the company she wants using the same type of query as the previous example When the FDC receives a request to buy a share through the same call as the queries the system checks the database to find the group controlling this shares sector shown in figure 14 If another group is in control the system sends a request to the relevant group if our team is in control we handle the request otherwise an error message is returned When
51. ecure communications were needed Our team took a lead on this issue proposing 1024 bit RSA encryption using SSL As a result of our research on the topic this was adopted as a standard in a subsequent meeting and successfully implemented by all groups Due to mistakes made out with our control our team were allocated 42 sectors more than all other groups collectively B1 O02 n3 o4 O5 52 Figure 7 Sectors as allocated to groups Our implementation was well capable of handling the extra load entailed 13 defero 74 Groups made good progress initially and in order to maintain the goodwill amongst them we offered to bring cakes to the subsequent committee meeting This proved successful and the practice continued with groups taking turns to bring the confectionary By taking an active lead in standards meetings we managed to implement our preferred solution to a number of problems such as the use of TCP and the format of XML communications This helped bring about an efficient decision making process The subsequent success of inter group communications at the integration test is a testament to this 5 3 Design Decisions The group allocated tasks where possible to group members who had previous experience in each area This is explained in more detail in the Allocation of Tasks section see page 31 however the specific design decisions are justified here The choices of implementation lang
52. ed by both parties and prevents inconsistencies and disputes occurring Each group is responsible for maintaining secure control over its private key because if this is compromised then an attacker could theoretically impersonate a group by using the port that the group is set up to use In the context of this project this is unlikely to because the we use a password to access the private key and only members of our project group know this password Security breaches If a group s private key was compromised then that group would notify the other groups and the relevant private key would be removed Whoever had breached the system would no longer be able to operate over the system because other groups would no longer recognise accept connections from the certificate used In the event of another of the project groups attempting to defraud the system by not updating a clients balance following a transaction it would be possible to prove since we maintain multiple logging functions which could then be used by an auditor to reconstruct the transactions and show that the other group had not correctly updated their clients balance If all groups use the logging system correctly then it shouldn t be possible for any single group to defraud any of the groups in the VSTM Our system defends itself against Distributed Denial of Service attacks in two ways Firstly by implementing a socket timeout after 8 seconds leaving time for incoming or out
53. ee E Qr EE ree ARP EES 49 9 Bibliography M 50 10 APDENGICES T T 51 defero 74 List of Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 Figure 19 Relationship between user and market maker sse 5 Group Communication Model eese nnne nennen en rennen enne 6 Abstraction of Model from Users sese ren eene enne 6 System structure split into logical components essere 11 Graphical Overview of Threaded System Operation sse 11 ecu EIECTUS 12 Sectors as allocated to PrOUDs eo rise etos rase te ona ee ein a EEDE nee e pott ee Paus voee pde gestes etn 13 State and server interaction model eene rennen nennen 16 Method for sorting Shares i ertet eene E oE eE OEA EEEE E EE E R EE 18 Parsing PLOCESS soroeensis en ers o eE e EEE E E E EE E E EEEE EE EO 22 Proposed Query Request Structure 1 essere nenne 23 Proposed Query Request Structure ii sse 23 Solution to Buffer Problem ssssessssesseseeeeereneenne emen nennen trennen nennen 24 Data flow for query requests 1 rer eter erheben PRESE EE EE tret ere Hn nhe EEEE 25 Abstraction of VSTM from UM
54. elopment process that can reveal both pitfalls with the design and errors made during the implementation Testing will be performed progressively through the implementation in order to identify problems as soon as possible With this in mind we will be using a number of levels for testing starting at individual functions and gradually integrating the various components until the entire system is in scope Function Level Testing At design level the inputs and outputs of each function known as methods in Java will be tested but not necessarily documented Creating documentation at this level would result in an unnecessarily verbose testing document Unit Level Testing The units known as classes in Java provide a logical way of dividing up the tasks between team members These tests essentially integrate related functions to test their compatibility The purpose of unit level testing is not to check the contents of individual functions this should have been done previously but to test the interactions between functions As this testing progresses it will be used at an increasingly high level First functions are tested together then the modules that they form until eventually the connectivity of system components has been tested As various deadlines are reached and prototypes created unit level testing may at times involve communications with other groups However the majority of this testing will take place at system level Syste
55. ensure that the components were functioning correctly Once this testing had been carried out it was possible for the system to be taken to a TUP test and tested against the other groups systems This allowed us to ensure that the code we were writing was compatible with the rest of the projects The TUP tests were designed to prepare us for the final demonstration at the end of the course We felt that we would benefit more at the final demo if we could maximise the lessons learned from the TUP tests and take a fully working tested project into the final demo 7 2 Integration Test Our final official integration test was held on 21 April Lasting just over an hour the team successfully traded with all operational market makers whilst answering questions from members of staff The team invited staff members to trade in some shares some making a distinct effort to test the robustness of the software Towards the end of the test we were given permission to deploy our groups testing tool name Crasher to test the robustness of all groups servers As stated in testing see page 34 Crasher launches a number of different Distributed Denial of Service P9 P DDoS attacks Ironically the effectiveness of the attack was muted by the already high server load We believe the attacks would have been more effective were the lab machines not under the stress of demonstration as not many of the attack threads 39 defern T4 we
56. entation ably storing everything required and searching efficiently and reliably for the duration of the project Despite various issues with Flash see page 15 this choice of interface provided an inventive graphical solution to the problem Most issues stemmed from the Macromedia developers of Flash implementation of Flash something relatively common with this kind of closed source system Despite these issues the feel that the choice was justified as it allowed us to widen our objects beyond the norm 7 6 Comparison With Other Groups Given the closed source nature of the project our comparison with other groups is based only on progress made and the respective interfaces chosen All groups were able to communicate successfully using our schema marking a great success for the team We successfully managed to keep up with the implementation schedule effectively created by the numerous TUPS during the second semester keeping us ahead of other groups implementations This gave us numerous advantages in testing our system and Evaluating other groups software gave us a post project insight into other ways we could have made our software Some other groups managed to incorporate features which we did not for instance group 3 s software was able to show a graph of stock prices This is a feature we would like to implement if we did further work on the project We felt that it was better to concentrate our efforts on a good softwar
57. ependant on the workload of other modules at any given time During but not limited to these meetings we will discuss progress made since the last meeting and any problems encountered or anticipated At the end of these meetings the group will crosscheck notes to ensure that no member is unsure of their charge Out with these meetings communication should preferably be verbal however failing that e mail through the group mailing list jh20055 dcs st andrews ac uk is available 3 2 Supervisor Meetings During term time the group will meet at least once a week with our supervisor to discuss progress and ensure that we are on target with our implementation and timescale The supervisor has stated that he can reply to e mails for any problems requiring immediate attention 3 3 Standards Meetings As stated in 1 4 the groups involved in this project have agreed to send a representative to weekly standards meetings These meetings are designed to create agreement on protocols for communication between groups Other groups can be contacted out with this meeting in person or via cs3099 stu dcs st andrews ac uk but decisions on standards issues can only be made and verified during the meeting It has been agreed that no person can represent his or her group in consecutive meetings 3 4 Customer Meetings When requested or granted by the customer one representative from the group will attend a customer meeting The customer can
58. er with groups having no control over its format or contents Share information was available as comma separated values XML or MFML invalid XML but with additional share information The XML feed was used initially however this didn t provide enough relevant information such as display name e g Vodaphone and sector e g Telecoms Wireless so the team switched permanently to the MFML feed Since finishing coding we have learnt that this wasn t done to specification as the MFML feed was only ever intended to be used initially with the XML feed used for updating data However as the specification was never given to groups this decision could never have been reasonably taken Created for the initial prototype the feed parser reads in the XML feed and parses this into a format readable by the rest of the system Initially this involved simply parsing the file using the Xerces Java parser As stated above it eventually became necessary to switch to an MFML feed which wasn t valid XML As a result prior to XML parsing the program must filter out the un escaped ampersands that rendered the feed invalid Once parsed the system can be used to store data in one of two ways 1 Stored as within a Java linked list original implementation Initially used as a quick implementation of a database this function still exists to be used as a back up in the case of any difficulties with the mySQL database The initial parser was based on a sec
59. er it is less intuitive interface Due to the lack of documentation trial and error had to be used to discover the programs functionality Additionally there were a few bugs in the user interface where prices were displayed behind buttons not surprising given the complexity of developing such a user interface 3 4 Summary From our context survey we have found that no current stock trading portfolio management systems have provided a user interface we find to be truly intuitive Web based user interfaces struggled to show all relevant data on a single page the user often has to swap between pages to find what they require This highlighted the importance of layout in displaying content Little user interaction is required in the form of data entry Consequently the layout of the user interface is a driving factor for an intuitive system However the TSimLite system suffered from similar problems leading us to conclude that neither system is ideal The scope of the project limits the depth of our program from areas such as dynamic graphing and advanced transaction types making it easier to fit relevant information into one page 3 5 References Stock broking Today J Dundas Hamilton MacMillan Press Ltd ISBN 0 333 24237 8 McGraw Hill Dictionary of Modern Economics Greenwald amp Associates McGraw Hill A Guide To Financial Markets Charles R Geisst MacMillan Press Ltd ISBN 0 333 30919 7 The Work of the Stock Exchange
60. er to the JDBCConnector neater and more extendable 49 m defero x 9 Bibliography 1 Group 5 Defero Project Specification 2005 see page 55 2 Group 5 Defero Project Plan 2005 see page 62 3 Group 5 Defero Interim Report 2006 see page 76 4 Hamilton J Dundas Stock broking Today MacMillan Press Ltd ISBN 0 333 24237 8 5 Greenwald amp Associates McGraw Hill Dictionary of Modern Economics McGraw Hill 6 Sir Stephen Killik The Work of the Stock Exchange E Couchman amp Co Ltd 7 Charles R Geisst A Guide To Financial Markets MacMillan Press Ltd 8 http finesse ac uk tags finesse html 9 Helliar amp Michaelson Evaluating Finesse Experiences from the First Year 10 DM Power R Michaelson C Allison 1998 The Finesse Portfolio Management Facility 9th CTI AFM Conference 11 http game marketwatch com 12 http www tradingsimulation com tsimlite 13 Spiral Model Diagram taken from http www stsc hill af mil crosstalk 2001 05 boehm html 14 Pressman R 2004 Software Engineering A Practitioner s Approach McGraw Hill Higher Education Page 35 15 16 17 18 19 20 21 22 23 Books 24 25 26 27 28 29 30 31 32 Knudsen J 1998 Java Cryptography O Reilly Burke E M amp Coyner B M 2003 Java Extreme Programming Cookbook O Reilly http www cs umd edu ben Norman D and Draper S 1986
61. erchants Clothing footwear Computer hardware Consumer electronics Diversified industry Education training Electrical equipment Eng Contractors Environmental control Food drug retailers Forestry Furn Floorcovering Gambling Gas distribution Gold mining Hospital management Hotels Hsehold apps hsewares Insurance brokers Internet Inv tst emerging mkts Inv tst venture dev Investment cos 6 Oil gas expl prod Other financial Other health care Other inv Trusts Paper Personal products Photography Property agencies Security and alarms Semiconductors Software Subscr Entertainment Telecom equipment Telecom fixed line Telecom wireless Textiles leather gds Venture capital trust 96 defero 74 10 10 Terminology Economics Terminology This section explains terminology used with reference to the mechanics of stock markets Stock Market Where stocks and shares are bought and sold a market in which the shares of corporations are traded Market Liquidity Market liquidity refers to the ability to quickly buy or sell a share without causing a significant movement in the price We wanted large sales or purchases to affect stock prices but this was unachievable given the resources and time we have Market Maker A group authorized to create and maintain a market one that stands ready to buy or sell shares at bid or offer prices throughout the business day Market makers attempt to profit from the b
62. esting as well as integration testing between all the separate groups The team conducted robustness testing with every group in the system including ourselves during the final demonstration at the end of the module This is also covered in the testing section Evaluation We conducted a concise evaluation of our system and this is discussed in the evaluation section Our implementation is compared to our original objectives to determine whether we accomplished all we intended We go on to contrast our system with various products discussed in the context survey conducted during the early stages of development Conclusion Our conclusion summarises what we have learnt and achieved whilst working on the project Drawbacks of the system are also discussed in order to show where we believe the project could be taken in the future Appendices The groups previously published documents the project specification and plan are included in the appendix In addition a maintenance document is included to aid in any future updating of the system Also included are the teams User Manual XML Schema and other reference documents The results of a user survey carried out by the team defero 74 4 Context Survey This section gives an overview of domain research the team carried out U to show what we are going to model what has been done before and what areas of the domain can be explored There are various s
63. estriction base xsd integer gt lt xsd minInclusive value 1 gt xsd maxInclusive value 5 gt lt xsd restriction gt lt xsd simpleType gt lt xsd attribute gt lt xsd attribute name type gt lt xsd simpleType gt lt xsd restriction base xsd string gt lt xsd enumeration value buy gt lt xsd enumeration value sell gt lt xsd restriction gt lt xsd simpleType gt lt xsd attribute gt lt xsd complexType name tradeRequest gt lt xsd sequence gt lt xsd element name official code type xsd string gt lt xsd element name currency type xsd string gt lt xsd element name price type xsd decimal gt lt This will be the OFFER price for buyRequests and the BID price for SellRequests gt lt xsd element name quantity type xsd integer gt lt xsd element name transaction id type xsd string gt lt xsd sequence gt xsd attribute ref group gt xsd attribute ref type gt lt xsd complexType gt lt xsd schema gt EV ET a i 87 defern Trade Reply Schema lt xml version 1 0 encoding utf 8 gt lt Written by Angus Macdonald Group 5 gt lt xsd schema xmlns xsd http www w3 org 2001 XMLSchema version 1 3 gt lt xsd element name tradeReply type tradeReply gt xsd attribute name group gt lt xsd simpleType gt xsd restriction base xsd integer gt xsd minInclusive value 1 gt xsd ma
64. eter University of St Andrews CS3099 Software Team Project Group 5 Gregory Bigwood gjb4 Duncan Fowler df15 Angus Macdonald adm15 Ewan Summers es54 defero 74 1 Abstract The stock market is a fast paced environment through which trading may be conducted from anywhere provided a market maker can be contacted We were asked to create a portfolio management system allowing users to manage their own shares and providing market making facilities for them and for the other groups taking part in the project We developed a user interface that allows the users to buy and sell shares distributed amongst the project groups where each user had a persistent account within our system The system was designed to be easy to use for new traders We built a fully functional system that we believe fulfils the customers requirements and gives good insight into the development of commercial portfolio management systems 2 Declaration We declare that the material submitted for assessment is our own work except where credit is explicitly given to others by citation or acknowledgement This work was performed during the current academic year except where otherwise stated The main text of this project report is words 22 413 words long including project specification and plan In submitting this project report to the University of St Andrews we give permission for it to be made available for use in accordance with the
65. face Internet Reuters historical data Figure 4 System structure split into logical components SystemStartup UpdateServer RequestServer UMS Server JDBC Connector Figure 5 Graphical Overview of Threaded System Operation 5 Development Model The team decided to adopt the spiral model I of software development see the diagram below We felt this system best represented the timescale and targets set out by the customer While the major project milestones tend to suit the waterfall model this model of development lacked the flexibility required for a project where the risk of requirements slippage was high We assumed this as the customer appeared to be unsure about the exact nature of the product they wanted and was vague 11 defer about exact requirement details The spiral model allowed for this kind of evolutionary development whilst maintaining the documentation structure of the waterfall model CUMULATIVE p 9T PROGRESS P DETERMINE ee EVALUATE OBJECTIVES ALTERNATIVES ALTERNATIVES IDENTIFY CONSTRAINTS RESOLVE RISKS j C J E RISK ANALYSIS RISK ANALYSIS COMMITMENT PARTITION REVIEW RQTS PLAN LIFE CYCLE DETAILED DESIGN SOFTWARE PRODUCT DESIGN REQUIREMENTS VALIDATION WATERERS DESIGN VALIDATION 44 plan AND VERIFICATION UNT N PLAN NEXT T
66. first a control program is used to launch attacks from the second a program that sits idly on a machine awaiting incoming TCP connections before attacking a designated target IP Control This program consisted of a simple command line user interface that asked for a group number and an IP address and attack type and a quantity of attacks to make Upon receiving this information from the user it spawns a large number of threads that all try and connect to a different machine in the third year lab in the hope of connecting to a running zombie program Zombie This sub system consisted on many small integrated parts The main program itself is called xml redirect in an effort to remain incognito to anyone checking processes currently running on their machine This spawns a small server system that listens for incoming connections from the control program The server spawns a number of threads equal to the quantity number received via the message from the control program The attack type is passed to the thread upon creation where the relevant attack is carried out It should be noted that if the user entered 20 into the quantity field in the control program then twenty attacks will be carried out by each machine running the zombie process This means that a large number of connections can be made against the target without having to create a large amount of shares in an individual zombie instanc
67. gh quality of documentation by allocating various tasks to individual group members to increase productivity and staging regular meetings to bring our material together and through discussion and review of the material ensure that it is of high quality 1 6 Project Monitoring We have allocated tasks to individual group members with deadlines for those tasks From this we have constructed a Gantt chart that details the deadlines of the project modules and the group members assigned to them Software Engineering 7 Ian Sommerville Pearson Addison Wesley 2004 64 defera 2 Module Overview and Implementation This section looks at the structure of the envisaged system describing the purpose of each module The following diagram shows an overview of this system Another diagram split into languages of implementation is shown below this Additionally a use case model and sequence diagram based on this system can be found in sections 8 2 and 8 3 of the appendix Market Maker User Management system User management system m interface Internet Reuters historical data High Level Overview 65 defern VSTM interfacing module Database Financial database data jdbc commands Data Centre Other groups database data jdbc commands Reuters historical data Flash php XML Web interface 2 Market Maker Component Language Based Organisation
68. going connections to finish reading or writing then freeing up the port for legitimate connections This prevents attackers from opening a connection and not sending any information with the intention of using up system resources and it also defends against problems caused when other groups crash but leave a connection Extensive testing highlighted this as the only event which caused our system to cease handling requests The timeout is set to 8 seconds and not sooner to allow for other groups to process our requests and format a response at high system load times this value is still fair Each socket connection is placed into a synchronized map that provides a vector for each connected IP address providing a second defence against DDoS attacks Each array has a size of 4 meaning that a 30 defero T4 maximum of 4 connections per IP address are allowed at any one point This defends against a multitude of connections coming in from a machine with the intention of overloading out system resources whilst allowing a reasonable number of requests through Each time a new connection is made from an IP address the corresponding vector contents are analysed and provided there is space the thread is created and inserted If the vector is full the system iterates over to find any dead threads which are removed allowing a new connection to be added If the vector is full with live connections then a thread will not be created and a con
69. h as for displaying stock information are used by the Virtual Stock Exchange Of particular note is the code to display graphs which are clear and easy to navigate The trading toolbox provides quick access to buying and selling from any page In our evaluation of the virtual stock exchange we found the trading procedure to be badly designed Although the trade stock helpfully displays the cash available to buy stocks it doesn t state the current price of the stock being bought the user has to remember this from the previous Screen 4 3 TSimLite Virtual TSimLite is a Windows based stock trading simulation program developed by a professional stock trader to help improve his trading It is a freeware program and uses a free financial data stream from DukasCopy Having a Windows based user interface makes it easier to organise data relevant to a transaction onscreen however it is less intuitive interface Due to the lack of documentation trial and defern T4 error had to be used to discover the programs functionality Additionally there were a few bugs in the user interface where prices were displayed behind buttons not surprising given the complexity of developing such a user interface 4 4 Summary From our context survey we found that no current stock trading portfolio management systems have provided a user interface we felt was truly intuitive Web based user interfaces struggled to show all relevant data on a single
70. ice This is the highest price that the market maker is willing to pay for a specific security Sector This is the sector the share is grouped in Last updated This is the time the share details were last updated The scrollable table can be sorted by code display name and sector in ascending and descending order To proceed buying a share click on the share you wish to purchase ze eee Den IEOR ah Gar jD ere ALL EAT A 82 defern After clicking on a share you will be forwarded to the buy selection screen as shown on the screenshot on the left This displays extra details about a share and allows a number of shares that you want to buy to be entered Clicking on the back button will take you to the search results If you click on the next button a confirm window will appear displaying the official share code offer price and number as shown on the screenshot on the right To close the window press the cross in the top right of the window or click the cancel button This will take you back to the buy selection screen Click submit to buy the share If the buy is successful you will be forwarded to the success screen otherwise an error will be displayed in the top right Sell When the sell button is clicked your portfolio details are shown You can click a share to forward to the sell selection screen as shown above Click on the next button and a confirm window will appear Click submit to sell the
71. id offer spread We are not a complete market maker as we can t provide liquidity see above however we maintain allocated sectors in a market Bid Mid Offer Prices The bid is the highest price that market maker is willing to pay for a specific share The offer is the lowest price acceptable to a market maker of the same share The highest bid and lowest offer are quoted and the difference between the two prices is called the spread giving the market maker us commission We the market maker e Sell you shares at the offer price asking price the lowest price acceptable to us e Buy shares back from you at the bid price the highest price acceptable to us The offer price is the higher of the two meaning you lose money if you sell back to the market maker us straight away this is the spread and its our method of getting commission The mid price is the price quoted if not otherwise stated i e in the view all shares list This is a rough average of the other two the mid 97 defero Selling Short A technique employed by investors who believes the market price of a share will drop The investor borrows stock which he then sells even though he doesn t own it If the price of the stock drops the investor can buy the same stock for less than what he originally sold it for and make a profit after paying the market maker commission for borrowing the stock The investor must return a
72. ing our group the standard for other groups to ensure compliance This charge ensured that there were few problems with secure communications at TUP s or the final integration test Communication between groups in the VSTM is created by a TCP connection The life cycle of this connection is defined by the communications protocol usually as long as the time it takes to send a message and receive a response Security between groups in the VSTM is provided by 1024bit RSA encryption using a Secure Socket Layer that for our team was provided by Java Each group has provided a virtual certificate that was given to all other groups This ensures communication only takes place between groups that have the private key that matches the 29 defero T4 corresponding certificate and the only certificates in use are those provided by the project groups This guarantees that anyone out with the five groups cannot trade over the VSTM as they can t have a valid certificate Non Repudiation This system also provides non repudiation because each project group has a corresponding certificate that only they should be able to use This means that a group cannot deny that a transaction occurred from their group because the IP port combination of a connection can be monitored and if the correct certificate is used then we know that a legitimate party has made a connection This ensures that the transactions that take place in the VSTM are not
73. ion further abstracting the database implementation from other sections of code Due to the consistent structure of the system all other database accesses follow the same pattern Such operations include validating Alice s login retrieving stock information and adding data from the XML feed Where data is updated the relevant data type is constructed from its source data then passed to the Database Manager which will ask the JDBC Connector to find the relevant records in the database and then to update them 27 defern 5 4 5 Logger FDC Logger eventLogger fdcLogger This package is responsible for the creation of logs a function requested by the customer post requirements specification The package allows for logs to be created for requests and replies to requests updates to the database and errors The former request log is required by the customer however other functionality was added for the logging of errors to exploit this feature for debugging All logs are written to a schema defined XML file allowing them to be transformed into HTML tables using XSLT Later in development a similar logging feature was added to the database helping to ensure the accuracy of our records The system is built with robustness in mind and as a result errors shouldn t affect the continued operation of the system While this is a positive feature it also means that any errors occurring during the integration of components are diffic
74. ioned previously Flash MX is geared towards producing movies Graphical user interfaces have multitudes of states which are changed based on user interaction A movie has two states playing and not playing Thus to use flash as a GUI we must build a state based system This was implemented by making specific frames in the main timeline states and by using control between states by calling ActionScript library movie functions To halt on a specific state we again call a movie function to stop the main timeline Although we now have strict state control we used persistent elements by allowing that element to span across the frames This keeps one instance of elements such as backgrounds that should exist in every state This creates a consistency across the whole interface by allowing features such as changeable colour schemes By breaking the ActionScript into functions code can be found quickly and is better formatted 15 defero 74 Tomcat server 1001 1003 6001 2003 2004 2001 Portfolio Options Logout Failed login Sell selection Search results Buy selection Buy Buy Fail Gives Buy Success Legend 1234 Communication with state code 1234 D All states are connected to the main gt Forced transition menu state apart from the login state Transition by user interaction Figure 8 State a
75. is is how the system was implemented The following table elaborates on this Group Member Tasks Angus Financial Data Centre temporary database initial prototypes XML Schema for all groups Duncan Database Database Interface URL encoder method Ewan User interface flash tomcat connection Greg User Management System tomcat server initial prototype Secure Communications for all groups 31 defern T4 The greatest improvement in the productive powers of labour and the greater part of the skill dexterity and judgment with which it is anywhere directed or applied seem to have been the effects of the division of labour eu We feel that the allocation of tasks to group members constituted a successful division of labour that matched individual talents and experience to system components Angus Tasked with both the creation of the FDC and with the format of inter group communications Angus was able to focus on XML manipulation in Java developing a strong understanding of the tools used Xerces Java XML tools In addition to developing his knowledge of XML and XML Schema he learnt XSLT used in a number of areas to improve efficiency The temporary database used in all but that last TUP represented a large part of the system code before being replaced by the mySQL database Duncan As the only group member with previous experience with mySQL Duncan was a clear choice for
76. ith the rest of the system It allows the user interface to interact with the VSTM and the database both through the FDC providing the functionality required to allow the end user to utilize the system to manage their portfolio The UMS performs relevant operations on the data as it passes through this section formatting and performing necessary calculations such as comparing an accounts balance to the cost of a requested transaction In this example this involves either forbidding the transaction or informing the user account database control classes of the required update to make followed by sending the request to the FDC Connections The user interface and the UMS exchange URL encoded data the servlet encodes the data and sends it to the interface via a TCP connection Every time the user interface needs to send data to the system the servlet is run connecting to a new thread on the UMS The lifetime of such a thread is the length of time it takes to receive the request and return a response before it is automatically garbage collected This allows a variable number of users to use the system at any one point but as a result of this implementation only active users need to have running threads freeing up system resources 19 defero T4 This component connects to the FDC for making requests through a single factory class invocation making communication a simple process The FDC replies in an XML format meaning the UMS has
77. l the details we wished to view at particular points of transactions Our implementation shows the most share details are at critical times such as buying and selling Confirmations are shown in windows allowing the customer to view the details the previous page if necessary TSimLite lacked an intuitive interface and our implementation recognised this attempting to make the interface as recognisable to a user as possible by using icons and data layout similar to major operating system We didn t suffer from alignment issues with our data since it is displayed in a firm table that when set up correctly will display the data in the same manner every time User interface aside the project our team took part in was substantially different to all public domain work that had been researched The distributed nature of our stock market created various unfamiliar challenges and a different focus for the system implementation Given the resources available for the task the team feel we have competed admirably against professional competition 46 defero 74 8 Conclusions 8 1 Achievements of Team The main goal of our teams project was to create a system that simulates buying and selling shares over a virtual stock trading marketplace VSTM This is an abstract notion representing the network of group project systems over which users will trade We feel we were successful in this aim and produced a product we are proud of On
78. lains every SHEEP code used 100 Invalid 110 Invalid XML 120 Invalid Request Format 130 Invalid Request Content 200 No Deal 210 Price too low 220 Price too high 230 Not enough shares available what 240 Too many shares requested 250 Wrong Market Maker 300 Internal Difficulties 310 Not Ready 400 Feed Difficulties 410 Data Incomplete 500 Not Found 510 No Shares Found Intentions 100 Invalid 110 Invalid XML queryRequest lt code gt BT lt code gt lt queryRequest gt 120 Invalid Request Format lt tradeRequest gt lt code gt BT lt code gt lt currency gt GBp lt currency gt 89 defero T lt tradeRequest gt This doesn t match the schema Code isn t an element in a tradeRequest 130 Invalid Request Content lt tradeRequest gt lt quantity gt 12 33523522 lt quantity gt lt tradeRequest gt This matches the schema but the contents of the elements are flawed 200 No Deal Designed to be used when the answer to a tradeRequest isn t a confirmation 210 Price too low The price a group has tried to buy at is lower than the offer price E g trying to buy shares in BT at 12 00 when the offer price is 13 66 220 Price too high The price a group has tried to sell at is higher than the bid price This might occur if you try to sell shares in BT at 12 00 when the bid price is 10 35 The other g
79. lease refer to http en wikipedia org wiki Standard for Handling of Exception Error Protocol _ 28SHEEP 29 91 c cdefern 10 8 User Survey Throughout development the creation of a simple easy to use interface was a priority In order to ensure this the team tested the interface on a number of naive users all students who don t study Honours Computer Science or Economics This section contains the results of the survey CS3099 Team 5 Stock stem Please answer the following questions circle where applicable gt Were you able to view your portfolio without reference to the documentation yes ho Were you able to buy a companies shares without reference to the documentation Were you able to sell shares from your portfolio without reference to the documentation Did you find it difficult to use any of the features of the interface without having lye to refer to the documentation Were you able to use other interface functionality to the desired effect with use of nol documentation provided Were you happy with the load times of the system on queries Geno If no please explain here If you have any comments on the design of the interface or suggestions for improvements please state them here Name fos Thomas Signature PotD C83099 Team 5 Stock trading system Please answer the following questions circle where applicable Were you able to view your portfolio without reference to the
80. led us to progress beyond the initial scope of the project Improvements can be made to any software system as there is not usually a definitive solution to any given challenge especially one of the scope and size of the software team project We feel we created a system that is capable of handling the addition of a great deal more functionality on its existing software model It would be possible to add a multitude of features very simply with only a minor amount of implementation meaning that the customer could take the system and advance it as they see fit Communication between team members was good at all times By ensuring that each team member felt useful and had the correct assignments we built up trust and good relationships without becoming to 47 defero 74 team orientated Each team member feels as though their abilities in software engineering communication and forethought have improved as a direct result of the project Communication between groups was generally good with groups working together during standards meetings each team committed to seeing the year succeed as a whole Having contributed a significantly large amount to the standards for the year we were able to oversee the development of many of the standards and were thereby able to keep all of the groups on fairly good terms and up to date with each others progress Due to time constraints experience and budget it would be irrational to think that
81. like number of shares of the borrowed stock to the stock lender If you believe the market price of a share will drop you can sell short Borrow shares and then sell them even though you don t own them If the price of the stock drops the investor can buy the stocks back for less than they sold it making a profit Buying Long This term refers to when a person owns a share with a view to it increasing value This long position would be established by buying and would profit when the price of the share goes higher Itis the opposite of a short position This is what most people would consider normal activity on the stock market Sector The category in which funds or companies are grouped essentially the type of work they operate in For example Tesco are in the Food amp Drug Retailers sector Project Terminology This section explains terminology used in the context of the project Virtual Stock Trading Marketplace VSTM An abstract notion representing the network of group project systems over which users will trade Distributed Attack Program DAP The term used to describe the program s the team wrote for use in robustness testing also performing various types of distributed attacks on groups servers during the final project demonstration Testing Universal Progress TUP This is the name given to the fortnightly integration tests all groups participated in Protocol The formal description of message format
82. ll button allows you to sell shares from your portfolio e By clicking the Logout button you will be logged out from your account Options The interface colour scheme can be changed by selecting a scheme and pressing the change scheme button There are 5 schemes to choose from the default is blue The account password can be changed by entering your old password a new password and the new password again as confirmation Click the change password button to set the new password 81 Buy DIA fom 2 AU CO Ty Fa for P ttn Pate D2 2000 10128 Tale um Ld n fa p DE teats Vu Aor 28 106 ndr d Won Ape V 2G ta ane DEO OU a LII LIII eee Ds far a poet pene Drude 28 20 3040 o 2 To buy a share you must first search for it You can do this by selecting the code or price less than less than equal to equal to greater or equal to or greater than a value that is entered As shown on the screenshot on the left click on the search button to retrieve the search result If you wish to display all shares you can simply click on the display all shares button After a period of time the search results page will be displayed as shown on the screenshot on the right The share results will be displayed in a scrollable table which contains the following details Code This is a word with maximum length of 4 letters that represents the share Display name This the name of the company in which the share is held Pr
83. ly affecting the stock s price e They expect at least one user to be allowed access to the market via our system e They expect the ability to manage a portfolio containing shares held by the user A portfolio is a collection of investments held by user s to the system 1 2 User Use Case The user will want to be able to login to the system to trade shares view their portfolio and to query share information The following example gives an idea of how a user might wish to use the system The user wants to check how their portfolio is performing They login to their account and view a list of shares they own with relevant details Wanting to know more about a particular share they choose to view expanded information on it Having looked at the data shown they decide they want to sell all their shares in the given company Stock broking Today J Dundas Hamilton MacMillan Press Ltd ISBN 0 333 24237 8 56 defern 74 Having sold these shares the user wishes to buy some more in a different company They query the shares available over the VSTM to find one of relevant interest to them Later having found a share they wish to purchase they are able to buy the share This is then added to their portfolio We hope to model this system 2 Objectives The objectives have been split into sections in order to show distinctions between various aspects of the project These have been further refined as primary essential
84. m Level Testing Once the units have been completed and tested individually full integration of the software can be performed Tests performed at system level are carried out through the user interface using tests to show that the system performs correctly over possible inputs As the software is part of a distributed system it should be tested that it performs correctly under correct incorrect and malicious behaviour from other systems This aspect of system level testing is most important as previous levels of testing will be unable to account for this aspect Alpha and Beta Testing Once internal testing has been performed and the system appears to be correct to widen the scope of the testing alpha and beta tests will be performed Alpha testing involves using the software over a 70 defern T4 period of time within the organisation in this case the group The software will be tested in the Junior Honours lab where the integration test will take place Beta testing involves distributing the software to a small group of testers These testers should preferably not be computer scientists to simulate use by a non expert user 6 Documentation Following the conclusion of the JH project in April team members will not be available to provide support for the system The system is likely to be deployed worldwide by our customer who wishes to provide educational establishments and corporate training facilities with a stock trading
85. marketplace For this both user and technical documentation needs to be produced so the software can be installed configured and used Based on these assumptions we have identified four types of users all requiring documentation managers system technicians programmers and users We intend to create documentation for each of these levels 6 1 Management Level Documentation will be a functional overview of the system This document should clearly specify the purpose and scope of the project As an example of usage a company manager could use this document to justify usage of the system This documentation should be created towards the end of development when it is clear what functionality the system has and what aspects are particularly noteworthy 6 2 User Level A manual aimed at beginner users to the system describing how to use the various features available After the software has been completed and tested internally a user manual will be written The focus of this documentation will be the user interface as this is the area users will come into contact with The user manual will be tested for clarity when it is given to beta testers along with the software Ideally the testers should only require help should a bug be encountered A team member other than the coder for a given section will ideally create this level of documentation This is based on the theory that programmers tend to miss out small but significant sections of thei
86. me computers ran so slowly the mouse was periodically freezing on the screen Setup In order to set up the robustness check it was necessary to run the zombie process on all lab machines In order to do this we created 2 bat files the first connected to every lab machine in turn and ran the program the second connected to every lab machine and killed all active jobs in our user space This meant we could very quickly turn the system on and off if necessary The attack control program was run off of one of these machines and called when necessary to send an attack 37 defero T Control Zombie Attack Control nm Controlslave Controlslave Xml redirect PF CUN 3 he Attacklistener Xmlrouter Figure 19 Flow of control within attack programs The above diagram illustrates the method of setting up attacks Multiple objects or lines indicate that this section of the code creates many more instances expanding the attack further Testing When it came testing the distributed attack program it was necessary to not alert the other groups that we were constructing such a program as this would probably have resulted in them to create far more secure systems than they otherwise would have With this in mind we only tested the DAP on our own system throughout development with two exceptions prior to the integration test
87. n this section we give an overview of domain research we carried out to see what we are going to model what has been done before in previous projects and what areas of the domain can be explored Stock exchanges are organised marketplaces where shares are bought and sold Stockbrokers act as agents to clients in the buying and selling of shares since no outside investors can deal on the stock exchange directly Shares that a client owns are contained within their stock portfolio There are various systems that allow clients to manage their portfolio Finesse Virtual Stock Exchange and TSimLite are examples of projects which model this portfolio management we hope to learn from the strengths and weaknesses of these 4 0 FINESSE Finesse Finance Education in a Scalable Software Environment is an educational tool created for university level economics students Finesse simulates real time stock trading using a computer system to manage a portfolio of stocks and shares It has a number of sponsors including Reuters who provide a real time data feed of stock information from the London stock market By using real stock data as opposed to simulated stock data Finesse makes the trading experience very true to that of a real stock trader Finesse has been designed to be very scalable as it is used in many different institutions and in practise can work as well with tens of students as with hundreds of students There is no minimum number of s
88. ncy type xsd string e timestamp type xsd string e bid type xsd decimal gt e mid type xsd decimal gt e offer type xsd decimal gt e exchange type xsd string gt e sector type xsd string gt es official code type xsdistring e disp name typese xsd string e dividend type xsd string gt te gt name queryRequest gt element nam element nam element nam element nam element nam element nam element nam element nam element nam element nam element nam element nam xsd choices lt xsdiattribute xsdsatpriput lt xsd complexType gt lt xsd schema gt nam e diy pay date type Kedistring gt e group use required gt type use required gt nam 85 defern Query Reply Schema lt xml version 1 0 encoding 2 utf 8 lt Written by Angus Macdonald Group 5 gt xsd schema xmlns xsd http www w3 org 2001 XMLSchema version 1 3 gt lt xsd element name queryReply type queryReply gt lt xsd complexType name queryReply gt lt xsd choice gt lt xsd element name share type share minOccurs 0 maxOccurs unbounded lt xsd element name error type error lt xsd choice gt lt xsd attribute name group use required lt xsd simpleType gt lt xsd restriction base xsd integer gt xsd minInclusive value 1 gt lt xsd maxInclusive value 5 gt lt xsd restriction gt lt xsd sim
89. nd server interaction model Graphical Design The graphical design of the Flash GUI was aimed to make any user instantly comfortable with the layout The original design stemmed from the login screen of mandrake Linux with a lighter coloured pane on top of a darker one As versions progressed a bar was added to the top to indicate which section the user was in In the final version this area has been used to display the logo and the indicating text was moved to light coloured panel giving it a more prominent position on the page To avoid making the interface confusing simple buttons were used for a number of in page buttons similar to Windows where Okay and Cancel buttons are simple boxes In contrast the main menu buttons are highly graphical so as to make common tasks instantly recognisable Again this is an attempt to make a user comfortable with the system through their previous experiences with modern operating systems interfaces When hovering over these menu buttons a small movie is played This gives indication to what this button does the portfolio button looks like a folder and when hover over occurs the folder opens and it uses functionality in flash that is difficult to achieve with say a Java implementation The team followed a number of HCI principles including the golden rules by Schneiderman 7 Most of these rules were applied during development but these rules in particular were consulted throughout
90. nection will not be made Through the eight second timeout the system ensures a constant turnover of threads to prevent any individual thread persisting for extended periods of time and denying service to incoming connections User Interface to Java Security To support user confidence in the system and to prevent malicious activity the User Interface uses an HTTPS connection to our web server the Tomcat system we use to run our servlet uses a 1024 bit RSA encryption system for these connections The user is given a certificate upon connection and must first tell the browser to accept this certificate to able to securely communicate to our web server A different private key and certificate on the User Interface side of the system to the one that is used communicating with other groups on the VSTM This increases security as in the event that security is breached on one side of the system the other side is not compromised When a servlet session times out the user is returned to the login screen and is asked to re enter their password This improves security since it means if a user leaves their workstation for an extended period of time whilst connected to our system a malicious party cannot use the system without having to login thereby preventing them from pretending to be a legitimate user 5 6 Allocation of Tasks Tasks were initially allocated to team members in the project plan page 72 and with a few minor exceptions th
91. not yet received In this case this is all shares greater Ouage See alphabetically than MNR This MNR works as all groups return shares in sorted alphabetically by code i Ge ftim 5 Continue this process until the z queryReply end tag is received this signifies that all shares have been Figure 13 Solution to Buffer Problem read Using this method updates are received from other operating market makers every minute along with the feed Request Handler Package fdc requestHandler All queries and transactions involving shares are handled within this package whether they re from within the system or the wider VSTM 24 un defern T4 In order to make requesting data as simple as possible requests are handled by way of factory classes This means that from the view of the calling module all requests are handled with the same call improving program modularity This code shown below initiates the request process as the following diagram illustrates RequestFactory rfactory new RequestFactory RequestProcessor rp rfactory getProcessor input Document doc rp start RequestFactory getProcessor J RequestProcessor start Process Request T request Database Interface Figure 14 Data flow for query requests Send to Relevant To VSTM gt N n Group E M Request Call gt Ch
92. ond year practical by Angus although this now barely resembles the original code 2 Stored in a mySQL database latter implementation While this package has no direct interaction with the database this feature requires calls to the database interface functionally distinguishing it from the original version Once the need to store share data locally was eliminated it became clear that parsing the XML file using Xerces was not the most effective method of altering the feed format Consequently the group looked into other means of achieving this goal eventually deciding to use Xalan an XSLT parser P PU This method eliminated the need for storing numerous Document objects within the program and significantly reduced the systems complexity computation time and memory requirements MFML Remove Invalid Feed MFML Chase XML gt __ XSLT Processor Add to Database Linked List EU to Internal ormat Schema Defined XML va Figure 10 Parsing Process 22 un defero 74 The flexibility of the conversion theoretically allows for another different data feed to be connected and used to update the database Only the XSLT file would need to be adjusted to fit the format of the feed The one remaining issue is that of real numbers the feed stores fractions in a human readable format e g 2 1 2 but one which is not easily readable by computers
93. ord function is called which uses a method to send an object to UMS A listener function is activated to wait for a reply If the reply is positive Alice has will be forwarded to her portfolio page Otherwise an error message will be displayed on the login screen to show login has failed Upon entering the portfolio page ActionScript is called to request portfolio details of this user This involves sending another request to the UMS Upon receipt of the reply the URL encoded reply to arrays These are then used to populate the table which displays the share details Alice can sell some of her shares by clicking on the sell button on the main menu at the bottom of the page On pressing this button Alice is forwarded to a new portfolio view allowing her to select a share to sell Once selected Alice is forwarded to the sell share page which uses another table to display the full details of the share Assuming Alice has selected the correct share she can now enter the number of shares she wishes to sell and press the next button which will produce a confirm window If Alice is happy with this trade she can click the submit button otherwise she can close the window by the cancel button or by pressing the cross in the top right of the window On pressing submit a function is called which again sends the data to the UMS and waits for a reply 5 4 2 User Management System UMS As the example of Alice shows the UMS links the user interface w
94. our team handles the request a query is made to the database confirming the price of the stock If confirmed a confirmation is returned to the calling class in our example this is the UMS but when other groups request the reply is sent back to the server ready to be sent back across the VSTM 25 defero 74 Server fdc requestHandler server As with the UpdateServer class in feedParser a new thread is created to run an instance of this class on start up as in figure 4 This allows the package to open a listening socket ready for inbound connections from the VSTM In addition all requests from the systems users are filtered through here Often requests are handled internally through a request to the database interface There are however a number of situations requiring communication with other groups in the VSTM In this situation a new secure SSL TCP socket is opened for communication with the relevant group and the request sent The connection is closed once a reply is received 5 4 4 Database The problem of storing manipulating and retrieving large quantities of structured data is central to this project A number of strategies exist for dealing with this problem in memory storage flat file storage and database oriented storage Using in memory storage would make data manipulation and retrieval a simple and fast process Unfortunately in the event of power loss all data would be lost and the data size may ex
95. pleType gt lt xsd attribute gt lt xsd complexType gt lt xsd complexType name sShare gt lt xsd sequence gt lt xsd elemen lt xsd elemen lt xsd elemen lt xsd elemen lt xsd elemen lt xsd elemen lt xsd elemen lt xsd elemen lt xsd elemen lt xsd elemen lt xsd elemen lt xsd elemen lt xsd sequence gt lt xsd complexType gt xsd complexType name error gt lt xsd sequence gt lt xsd element name number type xsd integer gt lt xsd element name description type xsd string lt xsd sequence gt lt xsd complexType gt name code type xsd string gt name currency type xsd string gt name timestamp type xsd string gt name bid type xsd string gt name mid type xsd string gt name offer type xsd string gt name exchange type xsd string gt name sector type xsd string gt name official code type xsdistring gt name disp name type xsd string gt name dividend type xsd string gt name div pay date type xsd string ae fe oe XT eV Se CC amp oe xsd schema 86 defern Trade Request Schema lt xml version 1 0 encoding utf 8 gt lt Written by Angus Macdonald Group 5 gt lt xsd schema xmlns xsd http www w3 org 2001 XMLSchema version 1 3 gt lt xsd element name tradeRequest type tradeRequest gt xsd attribute name group gt lt xsd simpleType gt lt xsd r
96. project as all parties were allowed to bring ideas to the table 8 2 Future Direction of Work This section gives details of the functionality the team would add given more time on the project It is split up into the main components of the system User Management System UMS A better shutdown routine should have been developed in co ordination with the user interface The currently implemented method for destroying threads when the servlet timed out works however a more robust system would be preferable 48 defero 74 User Interface Flash As with any project more functionality would be added given more time In particular data passed between Java and Flash is URL encoded in the other parts of the program XML is used Ideally we would like to use XML sockets however communication by XML is too convoluted without installing additional software such as Flash Remoting Pu allowing Flash to parse the XML The team considered that the Java component parse XML instead as it should be faster than ActionScript In the end this wasn t researched as without Flash Remoting the team had no option but to parse in Java A survey of the system was carried out see page 92 and from this several improvements were extracted They were as follows e Loading time for displaying all shares solution as discussed in previous Issues section of user interface documentation e Being able to search for the display name of a sh
97. r module that they deem too trivial to mention 6 3 System Technician Level Documentation will comprise of instructions on setting up the system This document should provide give step by step instructions for installing configuring and troubleshooting the software The nature of this document means that it may be written in a more technical style to the user manual and will be tested by peers of reasonable IT skills To make this testable we define the latter statement as meaning someone studying second year computer science or lower 71 6 4 Programmer Level defern This should be documentation on the code structure of the program If a developer wished to expand on the implementation following the integration test they could use this documentation to familiarise themselves with the code program structure and other relevant implementation details This level of documentation includes commented code and Javadoc created during implementation We have designed standards for comments detailed in section 4 1 Project Monitoring 7 1 Gantt Chart Ses TEE Av Mor 100508 Fr 22503 AM Weed 32 15 Sun EO AM Wed 301005 Sun 260206 OF Wed 309105 Sun 05 0208 ES Wed S115 Sun G6mQ0E GB Mor 260205 Mor 130202 OF Moe 060003 Fn DO308 AM Moe 960203 Fr toD OF Moe 080003 Fria ES Moe 080203 Fn13X308 Ge Wed 5008 Fr 240002 DF Moe 100808 Fr 22508 DF Memo Fn245398 ES Mer 10 0508 Mor 2
98. re spawned due to high system utilization and the server all the groups were running on has a lower specification than any individual lab machine Despite this at least one group were forced to restart their server due to load problems caused by the attack With respect to individual components of the system we can say the following e User Interface Users were able to buy and sell shares view their portfolio and customise their view However due to some problems the team could not create user accounts during the test this can be easily fixed e Financial Data Centre FDC o Feed Parser Updates were successfully carried out from other groups However due a problem with our feed reader we couldn t update automatically from the feed This problem can be easily fixed o Request Handler To our knowledge all requests were successfully processed whether from within our group or from other e User Management System UMS Correctly dealt with requests from the User Interface and effectively passed relevant information to both the database and the FDC e Database All requests to the database were successfully executed and logs were taken of transactions However there were some issues logging the price of sales back to the market e Logger Successfully logged all transactions as a back up mechanism to the database and the result of all updates and exceptions 7 3 Objectives This section assesses the objectives given in the teams Proje
99. reads in the program responsible for handling requests from other groups and for handling user requests In addition multiple concurrent requests are made possible as a new thread is spawned to deal with every request This and the strategic use of the synchronised keyword giving mutual exclusion at key points in the program allow our program to truly be a multi user system To test these measures the team used a number of creative testing methods including offering prizes to anyone able to crash our system and creating a Denial of Service Attack program see testing page 34 6 Testing 6 1 General Testing The team recognised software testing as a vital part of the software development process revealing problems in design and errors made during the implementation Testing in its various forms was performed progressively from the initial planning stage right through to the project demonstration When the system was first designed a set of scenarios were drawn up and used to analyse data flow and code dependencies These helped demonstrate that no components where missed from the plan and data required by each component was passed at the appropriate time Next came function level testing where the logical path of each function was followed through by the programmer and appropriate measures were inserted to handle boundary exceptional and erroneous inputs Test routines written to test each function as black box uni
100. respective of their source The latter independent processes refers to the Tomcat servlet flash and the main system all of which run separately In addition to these measures components in the system are structured into well defined packages with private and protected keywords being used where possible Not only did this help with modularity but also with the integration of various components ensuring conflicts were unlikely To prevent individual component failure affecting the whole project the team had numerous contingency plans for potential problems e A secondary temporary non persistent database structure was built early on and this can be used in the event of a database failure e The UMS and the FDC work independent of each other meaning failure in one doesn t seriously affect operation of the other Updates from the feed parser are executed periodically with the Update Server written in such a way as to make it easy to modify the timing As noted previously the flexibility of the feed conversion theoretically allows for another different data feed to be connected and used to update the database Only the XSLT file would need to be altered to fit into the format of the new feed 33 defern T4 As a multi user system design had to allow for multiple requests concurrently To achieve this aim the program makes extensive use of threads beginning with an initial start up thread This initiates other server th
101. rol classes and the user interface for support of the new functionality since the UMS has no data storage or direct involvement with the user Financial Data Centre Java The FDC is logically split into three sections updates from the feed a server handling communication from and to other groups and a request handling package Maintenance for these sections is made easier by the availability of JavaDoc for every class This document shows how to add functionality for a number of probable cases e Addition of Another Type of Request 52 defero L Requests are processed in the fdc requestHandler processing package Here the BuyRequestHandler java and QueryRequestHandler java classes handle trade requests and query requests respectively All requests are received as text but converted to XML Document objects Firstly RequestFactory java needs to be updated with calls to constructors in your new class This can be done by else if name equals requestName return new NewRequestHandler doc Where requestName is the name of your new request in the root object of the XML request and NewRequestHandler is the name of you request handling class Now that the factory returns an active instance of your request handler you need to implement this class Begin by creating the constructor used in the above call it passes in a Document object In this constructor the current implementation converts th
102. roup tells you this is too high by sending this sheep code 230 Not enough shares Alice tries to break the system by selling shares she doesn t own the system replies with 230 This tells her that she can t sell this many shares as she doesn t own enough 240 Too many shares requested Undeterred by her last attempt Alice tries to break the system again by buying 2 000 000 000 000 000 shares in BT Your group replies with 240 and includes the number of shares available in the description element 250 Wrong Market Maker You don t go to a cheese shop to buy a television so why go to group 3 when you want to buy shares in a software company Terrible analogy aside this is the tag you return when you someone requests to buy shares from you and you re not in control of that sector 300 Internal Difficulties 90 defero x 310 Not Ready Send this when your code isn t working or if you just can t be bothered 400 Feed Difficulties 410 Data Incomplete Use this code if access to the feed is required and it is displaying an error message In addition this can be used to indicate that the bid and or offer price is at 0 so you can t trade on this share at the moment 500 Not Found 510 No Shares Found You ve searched for GAME when this isn t a share code The other group replies to tell you that no shares matching this were found 510 For further information on SHEEP p
103. s and the rules that groups of computers must follow in order to exchange those messages Schema A description of the structure and rules for an XML document type 98 defero 74 Concurrent Versioning System CVS Used to back up and store a history of the changes made to a document or source code file during development System A collection of components organized to accomplish a specific function or set of functions In our case this includes all the software our group writes User A person that uses the system Virtual Stock Trading Marketplace VSTM An abstract notion representing the network of group project systems over which users will trade Feed Terminology This section explains terminology used within the data feed provided by the customer This data is also sent in inter group communications specified within the XML Schema see page 85 Code Share code The 1 5 letter abbreviated a company uses for listing on the stock exchange Mid Price The mid point between the bid and offer price quote in the market Buy Price The price at which another party will buy the stock Offer Price The price an investor can buy from the market also called the ask price Data Feed Stock data supplied by the customer Timestamp The time that the stock information was taken from the data feed IEEE Standard 610 12 99
104. s meant that we could debug our system without concerning ourselves with the servlet after initial setup and testing When a user invokes a user interface function requiring data from out with the user interface the servlet is invoked For example if our sample user Alice decides to log in the information from the user interface arrives at the Java servlet running on Tomcat and is then converted into a form that can be sent out to the UMS The information is sent to the UMS via a secure TCP connection The UMS receives state information from the user interface and therefore knows which of the methods within the UMS to call It then invokes a method from the database control class that deals with validating login details The reply from the database control class is then wrapped up and the result sent out to the servlet which forwards the result to the user interface informing Alice that she logged in successfully The only difference between the behaviour for login and any other message type is the method that it invoked within the UMS to process the data or results For example if Alice searches for every possible share in the database due to a buffer issue in Flash the shares must be wrapped up into small dynamically sized blocks that can be sent without worry of overloading the user interfaces character read buffer Similarly if Alice were to buy shares her balance must be retrieved from the database and the total cost of the sh
105. sfully implemented all of the standards proposed by the committee Functional Requirements Portfolio Management System The user will be able to buy shares from any group over the VSTM Partially We successfully purchased shares from every group with a market maker capability The user will be able to sell shares to the market maker over the VSTM Yes We successfully sold shares to all groups within the VSTM The user will be able to view their portfolio Yes Our system allows users to view their portfolio using the user interface 43 defero 74 The user will be able view expanded details of their shares including but not limited to Code Currency Timestamp Mid price Bid price Offer price Yes When a user receives the result of a query only a small part of this information is visible in the results screen however expanded details are available on the buy and sell screens to give the user all the relevant information to help them decide if a transaction is required The user will able to query stock details listed in 4 2 1 4 within the system and the wider VSTM Yes It is possible for a user to query any stock details within the VSTM and also from our teams system The system will have a graphical user interface This will Relay all aforementioned data to the user Inform the user of any errors should they occur Yes The user interface is th
106. share If the sell is successful you will be forwarded to the sell success screen otherwise an error message will be displayed in the top right of the Screen By clicking back you will return to sell view of your portfolio 83 Logout To logout from the system click the logout button This will take you to the login page 84 10 6 XML Schema c defern Query Request Schema lt xml version 1 0 encoding utf 8 lt Written by Angus Macdonald Group 5 gt xsd schema xmlns xsd http www w3 org 2001 XMLSchema version 1 2 lt xsd element name queryRequest type queryRequest xsd attribute name type gt lt xsd simpleType gt lt xsd restriction base xsd string gt lt xsd en lt xsd en xsd en xsd en xsd en xsd res xsd simpleType fxcdiattrrib xsd attribute name group gt lt xsd simpleType gt xsd restriction base xsd integer gt lt xsd minInclusive value 1 gt xsd maxInclusive value 5 gt lt xsd restriction gt lt xsd simpleType gt xsd attribu Lo umeration umeration umeration umeration va value EQ value LT value GT es EQ f gt umeration va triction gt T ue GEQ gt lt xsd complexTyp xsd choice xsd lt xsd xsd sd lt xsd lt xsd sxsd lt xsd xsd lt xsd xsd xsd code type xsd string gt e curre
107. sible causes of errors had to be checked and tested The system is able to cope with the following abnormal behaviour e Key methods within the class are synchronised preventing probable concurrency errors e Ifthe system tries to write to a log file that doesn t exist a new log file is created and all future updates are written to this e Ifthe system tries to write or create a log file that doesn t exist a new file is created and future updates are written to this e If a new log entry includes characters which may invalidate the XML file for example ampersands the parser escapes these characters with the official escape characters Planned Updates While there is currently no functionality to view these logs within the system XSLT is used to display the logs in a readable HTML table We hope to be able to allow administrators to view these files remotely from a browser window 5 5 Security In any system that is implemented there is a threat of attack or exploitation Even in a simulation such as our project there is a necessity to provide security to give the system credibility This security is provided by the use of data encryption and user identification at various points in the program This has the effect of making the system more robust by creating secure connections that can be relied upon to deliver data efficiently and without error Inter Group Security Our team were put in charge of security for the VSTM mak
108. stent values between invocations thus removing a lot of the state management required a decision team felt this would make the system simpler and easy to expand All the state information comes from the user interface in an effort to distribute processing and to reduce server load Servlet The user interface communicates with the UMS via a servlet This servlet is run on the Apache Tomcat platform The Flash interface hosted by Tomcat is returned to the user when they connect to the web server The flash interface sends secure messages to the servlet which wraps up the data and forwards it to the UMS Users are assigned a session in order to limit the strain on the web server and to give a degree of client side security Currently the session persists until 30 minutes of inactivity reducing server load as clients can t logon indefinitely This allows for a greater total amount of users which is highly beneficial if the system goes into widespread use The team decided to use a servlet for communication between the user interface and the UMS as the various alternatives such as XML sockets would have required extra software that would have increased cost for the customer As a result we decided on Tomcat as it is a freely available product 20 defern T4 The team decided to abstract away from Tomcat as it can be difficult to debug meaning the servlet simply formats the data passing between the user interface and the UMS Thi
109. structure as illustrated in the project plan see appendix page 64 These components were created upon analysis of our objectives and requirements For reasons of space we can t incorporate these here they can be found in the requirements specification on page 60 The implemented components reflect these requirements e User Interface The interface for the teams portfolio manager used by users of the system to trade in shares over the market e Financial Data Centre FDC o Feed Parser Parses stock data from the feed provided by the customer and sends to our database The timing of updates is controlled by a server thread within the FDC o Request Handler Handles requests made from other groups and our User Management System e User Management System UMS o The interface between the user interface and the rest of the system This component handles requests from the user interface performing necessary modifications on the data and routing relevant requests onwards e Database 10 defern o Handles all communication with the database This includes both share information and user details e Logger o Logs transactions made by the group and transactions made by other groups to our sectors o Logs the timing of updates from the feed and their success VSTM Market Maker User Management system pese Data pese User management system Other groups VSTM interfacing module et inter
110. sues with the server hanging a socket timeout was added e Without new lines at the end of requests some groups would not respond e Some groups changed their assigned port Since then our text based user interface had the ability to specify port 6 3 Robustness Testing The threat of malicious attack by outside parties is always a threat against distributed financial services With this in mind we created a distributed attack program 281291 called DAP to test robustness of all the teams Instead of focussing on the inherent weaknesses in the protocol such as defrauding a group by mimicking a different group we decided to attack teams including ourselves based on holes in our system found through testing This ensured that all problems found early in development were continually stress tested by this testing module 35 defero T4 Given our knowledge of the underlying communication model the team knew that each group would listen on a particular port If an attacker were to create a large amount of connections to this port either the systems memory would be filled with a large amount of connection processing routines or the available ports would all be filled and legitimate connections would not be accepted producing to a successful DDoS attack For our teams system to be seen to be reliable robust systems they would have to defend against such attacks We constructed two separate programs to test system robustness the
111. t been given on how the data feed is updated 2 1 2 Feed Parser This parses stock data from the feed provided and presents it in a format that the financial data centre can interpret a DOM tree an xml file rendered as an object within our application 2 1 3 VSTM Interfacing Module Transmits and receives XML over the VSTM to other groups This should have the ability to handle multiple incoming and outgoing connections concurrently based on a TCP socket system This should be designed to be easily modifiable as a result of changes agreed in standards meetings 2 1 4 Database This encompasses the actual implementation of the database and the functions required to parse data between it and the data centre module The database will store current and historical share information for our market and a transactions history We intend to use the JDBC package in JAVA to communicate with the database having received data from the Financial Data Centre Module 2 1 2 2 User Management Component 2 2 1 User Management System As can be inferred from the title this module administers user accounts and manages all communication from this component to the Market Maker section of the system 2 1 Interaction with the user interface is its other main function All user requests go through this module to avoid issues with access rights taking place This is designed so as to abstract the issue of multiple users away from the Market Maker
112. tead of trying to deal with a demanding mapping between the matrix index for that share and the row number or sorting the matrix according to how the table is sorted an alternative approach is used Upon clicking the row number is retrieved and from this row number the script gets the share code for that row Then by looping we can find the index for the matrix that contains this unique share code Thus we can index into the correct portion of the matrix to retrieve the specific share details independent of how the data is visually sorted Data is displayed A share is selected Share 1 Share 2 The row number is collected and used to Share 2 Share 3 Row number found gt Sok up the share code Share 3 Sharan from the datagrid Sort Share 4 Share 4 Share 5 Share 6 Share code of selected share Share 6 Share 5 F P Search for the share code in all the share elements in the global structure eso Hemmer amp 271 b34084 display all the details of In dec the chosen share sd Shares can now be a T T T displayed no matter Return the position of this share how they are sorted in the global structure Figure 9 Method for sorting shares 18 defero 74 Walkthrough Beginning our example Alice wishes to login to view her portfolio On pressing the login button the passw
113. the financial data centre module the VSTM interfacing module and the feed Parser The User management component consists of the accounts module the user management system the web interface and the accounts module These modules are designed to implement specific parts of the requirements as seen in our requirements document with the intention that when the modules and components are viewed as a whole system all the requirements outlined in our requirements document will have been fulfilled The modules have been divided into 3 unique areas based on the language of implementation that we intend to use These have been assigned to members of the group according to experience and ability in the language of implementation and the expected size of the module 1 4 Communications amp Standards Being a distributed system communication between nodes is critical to the operation of the system To ensure tight communication each group has agreed to hold weekly meetings to discuss protocols for communication These are known as Standards Meetings In these meetings only issues involving inter group communication can be debated thus avoiding discussion on implementation details These meetings among others are discussed in section in 3 3 1 5 Testing amp Documentation In this section of the document we discuss unit tests function test white box system testing black box alpha testing black box beta testing We also discuss maintaining a hi
114. the market Shares are allocated by sector which is a grouping approximately describing the operations of a company for example Tesco is in the Food amp Drug Retailers sector A list of the sectors allocated to each team can be found on page 96 Buy at Offer Price Sell back at Bid Price User Market Maker Figure 1 Relationship between user and market maker The above illustration shows how users interact with the market maker individual teams by buying and selling shares through them In addition each team maintains accounts for the users of their system with teams unaware of users other than their own Such accounts are called the Clients Stock Portfolio The stock market is a complex environment that new users could be expected to find difficult to understand We prioritised a highly usable interface designed to enable inexperienced users hesitant to deal with real money or not comfortable with the market procedure un defero zi The customer provided a data feed supplying historic stock information used by the groups to simulate a stock market This data is updated periodically reflecting changes in stock prices Initially the customer had the following requirements of the system e Ability to use the provided a data feed containing historical stock information so that all groups are trading on a liquid market This can be seen as the ability to buy or sell a stock quickly and in large volume wi
115. the product we created would best any commercial or industrial example of a portfolio management system However our project light on functionality in comparison to large commercial systems shows how a simple robust and secure model could be built upon by a small team to create a powerful tool aiding in software portfolio management We learnt a lot of transferable skills whilst developing and implementing our project skills not only transferable to later computing projects but also for any project we may tackle in the future Ability in project management and communication is useful throughout academia and the business world Additionally the importance of documenting and presenting a project is also now far more evident to all team members We would recommend to any team implementing the same project in the future that they make be sure to analyse their development and system models before implementation to ensure that they are the correct choices for their team Maintaining good communication between members and other teams is vital as is ensuring that team members are aware of and understand the progress in the other areas of the team We did not have a formal or informal management hierarchy with development decisions made democratically but crucially however each team member retained control of the implementation of their individual component This promoted growth and creativity within individual sections as well as for the whole
116. thout affecting the stock s price e Ability for user accounts allowing at least one user access to the market via our system e Ability to manage a portfolio containing shares held by the user a portfolio being a collection of investments held by user s to the system Figures 2 and 3 show how groups are expected to network with clients abstracted from the VSTM through each groups user interface User Interface N User E 7 Interface i User se N 7 Interface T m Se User NE he Interface Datis a gt 3 i Figure 2 Group Communication Model Figure 3 Abstraction of Model from Users The diagram to the right of the two shows how details of the distributed nature of the market are abstracted away from the user They are only aware of their interface and never know which group they ve bought or sold shares from only that it was from within the market 3 3 Aims of Report This report aims to provide a description of our team strategy to solving the problem and an analysis of the resultant system To accomplish this we have included the following sections e Project details The achievements of the project are discussed within the project details section along with the main features of the design and justifications for these ideas Key features are discussed in context of the component they belong to defero x Testing The testing section covers unit and team level t
117. to divide its functionality and reduce the complexity of its implementation This helps its portability and extendibility as one component can be replaced with another without impacting on the rest of the system The database itself is set up though a set of SQL scripts which can be quickly deployed on another compatible database server The SQL syntax was written in a standard manner close to ANSI SQL 92 so would require only minor changed to port to another database system such as PostgreSQL or Oracle All code related to connecting to the database is in its own class db JDBCConnector which would be the only point in the program where changes would be made if the database was ported to another database platform Extra functionality can be added to the data management engine without modifying the code that connects to the database The db DatabaseManager class has methods for retrieving adding removing and updating information in the database using the JDBCConnector If additional data structures are added to the database the relevant Java data structures will need to be added These can be added as new Java Classes in the common types package which is used across our system If the structure of the system grows it may be necessary to output data in new formats such as SGML or CSV One of the strengths of the design of the data management engine is that the data type classes can contain their own code to mutate themselves into the required form
118. to leave a stable version of their market maker running so we could test our system with theirs Likewise the team left our market maker running so other groups could test their system with ours We became confident from test runs that our server was very stable so in an effort to find any bugs the team offered a reward of two cans from the Computer Science vending machine to any individual who through malicious means or otherwise could cause our server to crash The offer lasted for two weeks in which time our server remained active giving us reassurance that our software was stable and providing invaluable testing data The offer of a reward encouraged other teams to do more destructive against our server which also helped verify that the system was able to work under high loads 6 0 TUP Testing Between the groups there were Testing Universal Progress TUP tests These tests were held twice every month between all groups and ensured that throughout development new and existing methods of communication were fully functional Such tests were useful as they effectively provided black box testing with each team trying hard to show up others This allowed for stability analysis and robustness checking of the core system which coupled with our distributed attack program see Robustness Testing below improved the quality of the implementation Some of the bugs that were found and resolved through these tests were e Is
119. ts are typically in the main methods of each class The team found that most programming faults were found at this level With these problems removed faults found later in testing were typically small implementation specific issues that were traceable and fixable Following on from this component level testing was used where components are large sections of the system such as the Financial Data Centre and the User Management System One technique used for this involved writing stubs that emulated the behaviour of other components For example before the user interface was connected to the user management system it was not possible to test how the database would react to various user input scenarios particularly that of many concurrent transactions To achieve this a stub was written to emulate these scenarios to ensure faults were found and corrected as early as possible Our system is itself part of a larger system the VSTM To test the system as an entire unit two testing strategies were used Firstly the system was tested against itself buying and selling shares from our sector and ensuring all components work together Secondly the system was tested against other 34 defero T4 groups systems during the twice monthly TUP tests These were important in gauging how all groups were interacting but two weeks is a long time between test runs given the short timescale of the project At TUP tests the team encouraged other groups
120. tudents that need to be using the system to make a realistic simulation as real data is being used Finesse uses a web based interface which simplifies deployment and makes it platform independent on the client side This web based interface has been criticised by developers working with finesse who have found it limits the flexibility for presenting the data 58 defero 74 3 2 Virtual Stock Exchange Virtual Stock Exchange is a web based stock trading simulator provided by the financial news website MarketWatch com Areas of the functionality in marketwatch com such as for displaying stock information are used by the Virtual Stock Exchange Of particular note is the code to display graphs which are clear and easy to navigate The trading toolbox provides quick access to buying and selling from any page In our evaluation of the virtual stock exchange we found the trading procedure to be badly designed Although the trade stock helpfully displays the cash available to buy stocks it doesn t state the current price of the stock being bought the user has to remember this from the previous Screen 3 3 TSimLite TSimLite is a Windows based stock trading simulation program developed by a professional stock trader to help improve his trading It is a freeware program and uses a free financial data stream from DukasCopy Having a Windows based user interface makes it easier to organise data relevant to a transaction onscreen howev
121. uages were based on the team s strengths The entire team had programmed in Java for over two years thus it was a clear choice Other languages such as C were considered however through discussion it was decided that with Java a more robust and modular system could be created 4 This is possible through its use of classes housing functions and objects allowing for true object oriented design MySQL was selected over PostgeSQL Oracle or file storage since it provided most of the features we required As an open source implementation already installed in the lab it was available and it offered high performance and functionality for simple communication with Java using JDBC It was also the only DBMS that team members had experience in an important factor in our decision allowing more time to be spent implementing features than learning the language mechanics We realised from our context survey page 8 that it would be advantageous to have a web based user interface The obvious solution for this would have been PHP the team had previous experience using Flash MX meaning a more graphical interface could potentially be made Although connecting Flash with Java was more challenging than connecting PHP and Java the team felt that flash was the more adventurous choice giving us greater control of graphical content 5 4 Design Overview Design of the aforementioned components began in earnest prior to the start of the second
122. ult to spot hence the error logging function Used correctly the system should create a log every time an exception is thrown not interrupting the programs operation group_num transaction_id data update_type success type v createRequestLogEntry createUpdateLogEntry createErrorLogEntry X UPDATELOGFILE element data element name E N e T a CNN eed p REQUESTLOGFILE element data element name EHHOHLOGFILE element data lement name S Il V appendLog This method adds the time amp date to the entry log document object log type The log file that is written to is outputToFile determined by og type Figure 18 Data flow through the logging package This diagram shows a simplified version of the module A number of other methods were created to log buying and selling both to other market makers and to ourselves To avoid duplication of code these 28 defero T4 methods then use two others one to append the new log onto proceeding ones and another to save this to disk To limit the number of parameters required in calls as much work as possible is done within this package This includes finding the origin of an error automatically done by throwing an exception and using the resulting stack trace to get the name of the calling method and class As logs are designed to be created frequently all pos
123. va 1 4 2 Tomcat 5 5 15 Web browser with flash plug in Deployment To start up the system run the jhProject Jan files by entering java cp mysqdl connector java 3 1 12 bin jar xerces jar systemStartup SystemStartup at the command line in the jhProject jan folder This will start the java program running It is possible to leave this program running by entering an ampersand at the end of the previous command line call The java program will then load up a small user interface that can be ignored in terms of normal operation and should only be used for debugging output Next the servlet will need to be deployed in order to do this enter your tomcat manager and select the defero war web app deploy this webapp The servlet will then attempt to contact the java program Once these steps have been followed the system should be set up and ready to use User Interface Flash This section should be easily modifiable to anyone with experience in Flash and ActionScript coding 51 defero T4 Low cost maintenance of the GUI is achieved by the modular design of the Flash All ActionScript is attached to frames through functions instead of being attached to elements in the frame This allows graphical elements to be altered at will providing they are given the same instance name The entire User Interface can be visually altered without needing to alter the communication structure or ActionScript Adding new functionality
124. were identified in the project plan as having high risk exposure and so all subsequent design has taken this into account As a result we have been able to adhere to deadlines as laid out in our project plan Gantt chart As our plan was drafted on the vague description initially provided by the customer the evolution of his requirements has slowly rendered a number of our requirements incomplete and produced others As a result of these changes a logging ability for transactions has been added to the initial requirements While intended for financial auditing this function also provides us with an additional tool for debugging Development to date has been modular with each team member working on their own modules constructively The following table shows the areas in which group members have been involved 77 defern Task Group Members Involved User Interface Ewan Tomcat Flash Java connectivity Greg User Management System Greg Logging Function Angus Database and Database interface Duncan Request Handling Angus Feed Parsing Angus XML Standards Schema Angus Our work towards the end of week 3 focussed on the creation of another prototype to be used in the next class integration test formally called a TUP The test was designed as a trial for our updated communication schema and was successful bar a number of minor problems The next milestone for the project is th
125. xInclusive value 5 gt lt xsd restriction gt lt xsd simpleType gt lt xsd attribute gt lt xsd attribute name type gt lt xsd simpleType gt lt xsd restriction base xsd string gt lt xsd enumeration value buy gt lt xsd enumeration value sell gt a xsds restriction gt lt xsd simpleType gt lt xsd attribute gt lt xsd complexType name tradeReply gt lt xsd choice gt lt xsd element name confirmation type confirmation gt lt xsd element name error type error gt lt xsd choice gt xsd attribute ref group use required gt xsd attribute ref type use required gt xsd complexType xsd complexType name confirmation gt lt xsd sequence gt lt xsd element name official code type xsd string gt lt xsd element name price type xsd string lt xsd element name quantity type xsd string gt lt xsd element name transaction id type xsd string gt xsd sequence xsd complexType xsd complexType name error gt xsd sequence lt xsd element name number type xsd integer gt lt xsd element name description type xsd string lt xsd sequence gt lt xsd complexType gt lt xsd schema gt 88 defern 10 7 SHEEP Codes All groups agreed to use the SHEEP system for maintaining inter group error message Our team was responsible for maintaining this list The following document specifies and exp
126. ystems that allow clients to manage their portfolio we inspected a few such applications with hope of learning from the strengths and weaknesses of these 4 1 FINESSE 100 Finesse Finance Education in a Scalable Software Environment is an educational tool created for university level economics students Finesse simulates real time stock trading using a computer system to manage a portfolio of stocks and shares It has a number of sponsors including Reuters who provide a real time data feed of stock information from the London stock market By using real stock data as opposed to simulated stock data Finesse makes the trading experience very true to that of a real stock trader Finesse has been designed to be very scalable as it is used in many different institutions and in practise can work as well with tens of students as with hundreds of students There is no minimum number of students that need to be using the system to make a realistic simulation as real data is being used Finesse uses a web based interface which simplifies deployment and makes it platform independent on the client side This web based interface has been criticised by developers working with finesse who have found it limits the flexibility for presenting the data 4 2 Virtual Stock Exchange Virtual Stock Exchange is a web based stock trading simulator provided by the financial news website MarketWatch com Areas of the functionality in marketwatch com suc

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