Avaya X.25 User's Manual
Contents
1. rrrrnnrrnnonnvnrnnrrvnnnnnnnennr 1 2 Figure 1 2 How X 25 Gateway Establishes a Session X 25 Initiated oe om 1 5 Figure 13 Reestablishing X 25 Connections mmnmarmeummr eensessunvenamisisevermisvje 1 9 Figure 1 4 Reestablishing TCP IP Connections ooooor nosnnnovn r no nn neni 1 9 Figure 1 5 How X 25 Gateway Establishes a Session TCP Initiated meres 1 10 Figure 1 6 Role of the X 25 and TCP Protocol Stacks in X 25 Gateway 1 11 Figure 2 1 IPEX Mapping Add Window for Source PVC rrrrrrannnrnrnnnnnnrnnvennnnnnnnnnnn 2 4 Figure 2 2 IPEX Mapping Parameters Window for PVC mrrnrnrnnrrnnnnnvnnenvrnnnnrrnnennnn 2 8 Figure 2 3 IPEX Mapping Parameters Window for SVG rmnrnnrnnrrnnnnnvnnenrrnnnnrrnnennne 2 8 Figure 2 4 IPEX Mapping Parameters Window for TCP cccsceeeceeeeeeeeseeeeeeeeeeees 2 9 Figure 2 5 IPEX Mapping Table Configuration Window mrenrnnnnnvnnnnnvnnrnnrnnnnnnnnrenr 2 13 Figure 2 6 IPEX Mapping Replication Window mnrnnrnnnnnvnnnonrnnnnnrnnannvennnnrnnnnnnennenr 2 15 Figure 2 7 IPEX Mapping Table Configuration Window After Replicating a PVC to TCP Connection rrnannnvnnnnnvnnnnnvnnnnnvvnnnnvnnnnnnennnnr 2 16 Figure 2 8 IPEX Mapping Table Configuration Window After Replicating a TCP to PVC Connection muumemenenseiensnnenmmneei 2 17 308649 14 00 Rev 00 vii Preface This guide describes X 25 Gateway services and what you do to2. Values Help 308649 14 00 Rev 00 2 15 Configuring X 25 Gateway Services Done Gateway PYC gt TCP LCN 1 sre cct MCT1 21 1 Gateway PYC gt TCP LCN 2 sre cct MCT1 21 1 Gateway PYC gt TCP LCN 3 sre cct MCT1 21 1 Gateway PYC gt TCP LCN 4 sre cct MCT1 21 1 Gateway PYC gt TCP LCN 5 sre cct MCT1 21 1 Gateway PYC gt TCP LCN 6 sre cct MCT1 21 1 Gateway PYC gt TCP LCN 7 sre cct MCT1 21 1 Gateway PYC gt TCP LCN 8 sre cct MCT1 21 1 Gateway PYC gt TCP LCN 9 src cct MCT1 21 1 Gateway PVC gt TCP LCN 10 src cct MCT1 21 1 Help EEE P Add Copy Delete Apply Values eQcacaaaaaakh Enable ENABLE 7 Source X 121 Address Destination X 121 Address Destination PYC LCN Remote IP Address Remote TCP Port Number Figure 2 7 IPEX Mapping Table Configuration Window After Replicating a PVC to TCP Connection 2 16 308649 14 00 Rev 00 Enabling X 25 Gateway E Gateway TCP gt PVYC Port 12305 sre cct MCT1 21 Done Gateway TCP gt PYC Port 12306 sre cct MCT1 21 Add Gateway TCP gt PYC Port 12307 sre cct MCT1 21 Gateway TCP gt PYC Port 12308 sre cct MCT1 21 Copy Gateway TCP gt PYC Port 12309 src cct MCT1 21 Delete Gateway TCP gt PYC Port 12310 sre cct MCT1 21 Gateway TCP gt PYC Port 12311 sre cct MCT1 21 Apply Gateway TCP gt PVC Port 12312 sre cct MCT1 21 Values Gateway TCP gt PYC Port 12313 sre cct MCT1 21 Help
3. 121 called address 1 6 without called X 121 address 1 7 T T1 interface 1 1 TEP description of Gateway connection 1 10 interface 1 4 large data message 1 12 port number 1 4 2 11 protocol stack 1 11 socket 1 6 1 7 unstructured stream protocol 1 12 TCP Circuit Name parameter 2 6 TCP Header Type parameter 2 6 TCP IP to X 25 gateway 1 2 technical publications xii technical support xii terminal X 25 establishing connections from 1 6 text conventions x token ring 1 1 308649 14 00 Rev 00 translation stream 1 8 establishing TCP initiated 1 10 establishing X 25 initiated 1 5 X 25 to TCP 1 11 Transmission Control Protocol See TCP transmission unit maximum 1 12 W windows IPEX Mapping Add 2 4 IPEX Mapping Parameters PVC 2 8 SVC 2 8 TCP 2 9 IPEX Mapping Replication 2 15 IPEX Mapping Table Configuration 2 13 IPEX Mapping Table Configuration After Replication PVC to TCP Connection 2 16 TCP to PVC Connection 2 17 X X 121 called address 1 3 1 6 1 7 X 121 Called Address parameter 2 10 X25 Gateway definition of 1 1 large data message 1 12 Level 2 LAPB only interface 1 1 1 3 Level 3 PLP interface 1 1 1 3 message based protocol 1 12 networks 1 1 protocol stack 1 11 PVC 1 1 SVC 1 1 VC 1 1 Index 3
4. Done Gateway PYC gt TCP LCN 1 sre cct MCT1 21 1 d Add Copy Delete Apply Values Help jal SSZ Enable ENABLE p Source X 121 Address Destination X 121 Address Destination PYC LCN Remote IP Address Remote TCP Port Number Figure 2 5 IPEX Mapping Table Configuration Window To replicate a PVC to TCP or TCP to PVC configuration complete the tasks in the following table 308649 14 00 Rev 00 2 13 Configuring X 25 Gateway Services Site Manager Procedure You do this System responds 1 Choose the configuration you want to replicate and click on Copy The IPEX Mapping Replication window opens Figure 2 6 2 Set the following parameters Click on Help or see the parameter descriptions beginning on page 2 18 Number of instances First LCN number First TCP port number TCP port number increment 3 Click on OK The IPEX Mapping Table Configuration window reopens Figure 2 7 for PVC to TCP Figure 2 8 for TCP to PVC It now lists all of the connections you have configured with the Copy button 4 Click on Done You return to the X 25 Service Configuration window 5 Click on Done You return to the main Configuration Manager window 2 14 308649 14 00 Rev 00 Number of instances First LCN number First TCP port number TCP port number increment Figure 2 6 IPEX Mapping Replication Window Enabling X 25 Gateway Cancel OK
5. Options Function Instructions MIB Object ID Parameter Default Options Function Instructions MIB Object ID Enabling X 25 Gateway First TCP port number None For a PVC to TCP connection this value can be any valid port number For a TCP to PVC connection this value must be within the range of TCP ports reserved for Gateway service 12 304 to 16 399 Identifies the number of the first TCP port that will use the replicate configuration Enter the first TCP port number Not applicable TCP port increment None Any integer You can assign all of your replicates to the same port in which case you enter 0 for this parameter or you can assign each its own port by adding a value to each succeeding port number In the example given in Figure 2 6 each succeeding port is incremented by a value of 1 Instructs the router how to increment port numbers assigned to each of the replicate configurations Enter a value Not applicable 308649 14 00 Rev 00 2 19 A acronyms Xi adding an IPEX mapping entry 2 2 address called X 121 1 6 block message 1 13 boundary message 1 12 C called X 121 address 1 3 1 6 SVC with 1 6 SVC without 1 7 channel 1 7 circuits interface 1 6 configuration file preparing 2 1 replicating 2 12 Configuration Manager 1 1 configuring IPEX mapping parameters 2 7 congestion 1 3 1 5 connection automatic reestablishment after a fault occurs 1 8 f
6. TCP and X 25 communication stacks share the responsibility for maintaining reliable and efficient data flow If data loss occurs on one side that side retransmits the lost data In addition both sides independently maintain protocol flow control Data loss may result from either software or hardware errors or catastrophic failures Redundancy in network design is critical for handling these types of data communication failures Handling Large Data Messages X 25 is a message based protocol and TCP is an unstructured stream protocol They differ in the way they send outgoing traffic and deliver incoming traffic to their clients How X 25 Handles Large Data Messages When the X 25 client submits an X 25 message that is larger than an X 25 packet size the X 25 protocol fragments the message X 25 then transmits the sequence of packets containing these fragments Within each packet X 25 includes a flag that indicates the fragmentation and aids in the reassembly process at the receiving end How TCP Handles Large Data Messages TCP on the other hand does not have a flag to mark fragmentation of messages that are larger than the TCP maximum transmission unit MTU size The portion that does not fit into one TCP data segment is sent in a subsequent data segment Without the flag and any indication of the size of the message the TCP client has no way of determining the boundary of a message that is whether the complete message is contain
7. accompany the delivery of this computer software the rights of the United States Government regarding its use reproduction and disclosure are as set forth in the Commercial Computer Software Restricted Rights clause at FAR 52 227 19 Statement of Conditions In the interest of improving internal design operational function and or reliability Nortel Networks NA Inc reserves the right to make changes to the products described in this document without notice Nortel Networks NA Inc does not assume any liability that may occur due to the use or application of the product s or circuit layout s described herein Portions of the code in this software product may be Copyright 1988 Regents of the University of California All rights reserved Redistribution and use in source and binary forms of such portions are permitted provided that the above copyright notice and this paragraph are duplicated in all such forms and that any documentation advertising materials and other materials related to such distribution and use acknowledge that such portions of the software were developed by the University of California Berkeley The name of the University may not be used to endorse or promote products derived from such portions of the software without specific prior written permission SUCH PORTIONS OF THE SOFTWARE ARE PROVIDED AS IS AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES INCLUDING WITHOUT LIMITATION THE IMPLIED WARRANTIES OF MERCHANT
8. associated user manual solely in support of authorized use of the Software by Licensee This license applies to the Software only and does not extend to Nortel Networks Agent software or other Nortel Networks software products Nortel Networks Agent software or other Nortel Networks software products are licensed for use under the terms of the applicable Nortel Networks NA Inc Software License Agreement that accompanies such software and upon payment by the end user of the applicable license fees for such software 2 Restrictions on use reservation of rights The Software and user manuals are protected under copyright laws Nortel Networks and or its licensors retain all title and ownership in both the Software and user manuals including any revisions made by Nortel Networks or its licensors The copyright notice must be reproduced and included with any copy of any portion of the Software or user manuals Licensee may not modify translate decompile disassemble use for any competitive analysis reverse engineer distribute or create derivative works from the Software or user manuals or any copy in whole or in part Except as expressly provided in this Agreement Licensee may not copy or transfer the Software or user manuals in whole or in part The Software and user manuals embody Nortel Networks and its licensors confidential and proprietary intellectual property Licensee shall not sublicense assign or otherwise disclose to any third party
9. block may be transmitted in several TCP data segments With the 2 byte length field the maximum length of a message block that X 25 Gateway can send and receive using TCP is 64 KB Note While the maximum length of the X 25 message that X 25 Gateway can send to the terminal is 64 KB the maximum length of the X 25 message that X 25 Gateway can receive from the terminal is 4 KB 308649 14 00 Rev 00 1 13 Chapter 2 Enabling X 25 Gateway This chapter as outlined in the following table describes how to use the Configuration Manager to set up X 25 Gateway services Section Page Preparing a Configuration File 2 1 Configuring X 25 IPEX Services 2 1 Enabling X 25 Gateway Services 2 2 Replicating a Configuration 2 12 Preparing a Configuration File Before you configure X 25 Gateway 1 Create and save a configuration file that has at least one WAN interface 2 Retrieve the configuration file in local remote or dynamic mode 3 Specify router hardware if this is a local mode configuration file Refer to Configuring and Managing Routers with Site Manager for instructions Configuring X 25 IPEX Services When you enable X 25 Gateway services you must configure X 25 IPEX services Refer to Chapters 3 and 4 of Configuring X 25 Services for instructions on enabling X 25 and editing X 25 parameters Refer to Chapter 5 of that guide for instructions on configuring IPEX 308649 14 00 Rev
10. consisting of two Nortel Networks router systems and a TCP IP network The top system serves as a TCP IP to X 25 gateway The bottom system serves as a TCP IP to LAPB gateway In this example terminals connected to X 25 networks can exchange messages with host systems on a TCP IP network through the Nortel Networks routers using the X 25 Gateway service X 25 er TCP X 25 Level 3 92teway TE Heen router _ connections TCP IP host Loe concentrator TI links m J gt V 35 or FE EEE gt Physical V 35 links Figure 1 1 X 25 h gt LAPB 4 gateway ost S concentrator TCP IP X 25 Level router LAPB connections X250022A Sample Network Topology Using X 25 Gateway The router translates data received from X 25 virtual connections into TCP data packets and forwards those packets out through TCP connections The router also translates data received from TCP connections into X 25 data and forwards the data out through X 25 connections You can connect the equipment to the router by a leased line an X 25 packet switched network or a T1 or E1 circuit switched network You can also configure the router as a TCP IP to CCITT now ITU T X 25 Level 2 gateway as in the bottom part of Figure 1 1 This configuration allows access from LAPB based X 25 Level 2 equipment with no X 25 Level 3 support This manual refers to this feature as LAPB only su
11. e Process received data delivered from the X 25 module e Control the flow of data across the client interface X 25 Level 2 LAPB Only Interface X 25 Gateway also supports a direct LAPB interface so terminals can transfer data in LAPB format without using the X 25 packet layer You can select specific LAPB link circuits for the translation service to use instead of the X 25 PLP 308649 14 00 Rev 00 1 3 Configuring X 25 Gateway Services TCP Interface X 25 Gateway appears to TCP as a client As such the software specifies one socket for the local TCP interface consisting of its IP address and TCP port number and another socket for the remote TCP interface to establish a connection Each X 25 connection corresponds to only one TCP connection Since many TCP connections may be active concurrently to support many Gateway sessions a large range of TCP port numbers creates separate sockets for individual sessions The port numbers reserved for X 25 Gateway service are 12 304 to 16 399 X 25 Gateway uses the TCP client interface to e Open close and check the status of TCP connections e Send data to the TCP module for transmission e Process received data delivered from the TCP module e Control the flow of data across the client interface What X 25 Gateway Does X 25 Gateway consists of a source circuit and a destination circuit The gateway receives the first incoming connection on the source circuit and attempts to est
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14. 00 2 1 Configuring X 25 Gateway Services Enabling X 25 Gateway Services To enable X 25 Gateway services 1 Add an entry to the IPEX mapping table 2 Choose Gateway as the IPEX Mapping Type 3 Configure mapping parameters Use the following instructions to add an IPEX mapping entry and choose Gateway as the mapping type Adding an Entry to the IPEX Mapping Table Complete the following steps to add an entry to the IPEX mapping table Site Manager Procedure You do this System responds 1 In the Configuration Manager window select Circuits gt Edit Circuits The Circuit List window opens 2 Choose an X 25 interface then click on The Circuit Definition window opens Edit 3 Choose X25 Protocol gt Service The X 25 Service Configuration window appears It lists all currently defined network service records 4 Choose the network service record you want to configure for X 25 Gateway services 5 Click on Add The X 25 Service window opens Position your cursor in the Type parameter bar click on the Values button and choose IPEX as the service type continued 2 2 308649 14 00 Rev 00 Enabling X 25 Gateway Site Manager Procedure continued You do this 7 Edit the following parameters as appropriate to your network Use Help or see the parameter descriptions in Configuring X 25 Services First PVC LCN Number of PVC LCN System res
15. 121 Address X 25 Call User Data Figure 2 4 IPEX Mapping Parameters Window for TCP Parameters for PVC and SVC Connections Parameter descriptions for PVC and SVC connections follow Parameter Default Options Function Instructions MIB Object ID Source PVC LCN None 1 to 4095 Specifies the inbound PVC LCN that you map to the TCP connection The port monitors the X 25 calls for this LCN to initiate the connection This window appears only if you chose PVC as your source connection type Enter the LCN of the PVC for this IPEX connection Not applicable 308649 14 00 Rev 00 2 9 Configuring X 25 Gateway Services Parameter Default Options Function Instructions MIB Object ID Parameter Default Options Function Instructions MIB Object ID X 121 Called Address None Any valid X 121 address Specifies the inbound X 121 called address that you map to the TCP connection The port monitors the X 25 calls for this X 121 called address to initiate the connection This window appears only if you chose SVC as your source connection type Enter the called X 121 address up to 15 decimal digits The destination address depends on the network device to which this circuit is connected Consult your network administrator for the correct value 1 3 6 1 4 18 3 5 15 2 1 6 Remote IP Address None Any valid IP address Specifies the remote IP address used to establish a TCP connectio
16. 5 Gateway or remote TCP IP host interface X 25 TCP IP T host oute X 25 terminal K X 25 TCP interface connections down reestablished X250025A Figure 1 4 Reestablishing TCP IP Connections Establishing Connections from the TCP IP Host When a TCP IP based system issues a connection request X 25 Gateway performs the sequence of actions shown in Figure 1 5 308649 14 00 Rev 00 1 9 Configuring X 25 Gateway Services X 25 TCP IP spat su host os terminal Step 1 Connection requested X 25 TCP IP pees eae host terminal Step 2 Tj Reguest X25 pending connection X 25 attempt TCP IP ee Se host terminal Step 3 7 D Reguest X25 pending connection X 25 accepted gateway TOPP router X 25 nee terminal Porte Step 4 _ U ON Reguest X 25 accepted connection established X 250026A Figure 1 5 How X 25 Gateway Establishes a Session TCP lnitiated After establishing the X 25 connection X 25 Gateway accepts the TCP connection This one to one connection mapping provides another consistent and reliable session The mapping information you need to configure is e The circuit interface on which X 25 Gateway establishes the TCP connection The TCP port number that uniquely identifies the translation session e Th
17. ABILITY AND FITNESS FOR A PARTICULAR PURPOSE In addition the program and information contained herein are licensed only pursuant to a license agreement that contains restrictions on use and disclosure that may incorporate by reference certain limitations and notices imposed by third parties ii 308649 14 00 Rev 00 Nortel Networks NA Inc Software License Agreement NOTICE Please carefully read this license agreement before copying or using the accompanying software or installing the hardware unit with pre enabled software each of which is referred to as Software in this Agreement BY COPYING OR USING THE SOFTWARE YOU ACCEPT ALL OF THE TERMS AND CONDITIONS OF THIS LICENSE AGREEMENT THE TERMS EXPRESSED IN THIS AGREEMENT ARE THE ONLY TERMS UNDER WHICH NORTEL NETWORKS WILL PERMIT YOU TO USE THE SOFTWARE If you do not accept these terms and conditions return the product unused and in the original shipping container within 30 days of purchase to obtain a credit for the full purchase price 1 License Grant Nortel Networks NA Inc Nortel Networks grants the end user of the Software Licensee a personal nonexclusive nontransferable license a to use the Software either on a single computer or if applicable on a single authorized device identified by host ID for which it was originally acquired b to copy the Software solely for backup purposes in support of authorized use of the Software and c to use and copy the
18. BayRS Version 14 00 Part No 308649 14 00 Rev 00 September 1999 4401 Great America Parkway Santa Clara CA 95054 Configuring X 25 Gateway Services NORTEL NETWORKS Copyright 1999 Nortel Networks All rights reserved Printed in the USA September 1999 The information in this document is subject to change without notice The statements configurations technical data and recommendations in this document are believed to be accurate and reliable but are presented without express or implied warranty Users must take full responsibility for their applications of any products specified in this document The information in this document is proprietary to Nortel Networks NA Inc The software described in this document is furnished under a license agreement and may only be used in accordance with the terms of that license A summary of the Software License is included in this document Trademarks NORTEL NETWORKS is a trademark of Nortel Networks Bay Networks and FRE are registered trademarks and BayRS is a trademark of Nortel Networks All other trademarks and registered trademarks are the property of their respective owners Restricted Rights Legend Use duplication or disclosure by the United States Government is subject to restrictions as set forth in subparagraph c 1 1 of the Rights in Technical Data and Computer Software clause at DFARS 252 227 7013 Notwithstanding any other license agreement that may pertain to or
19. CA 800 2LANWAN 800 252 6926 Valbonne France 33 4 92 96 69 68 Sydney Australia 61 2 9927 8800 Tokyo Japan 81 3 5402 7041 xii 308649 14 00 Rev 00 Chapter 1 X 25 Gateway Overview X 25 Gateway lets you send and receive messages between X 25 and Transmission Control Protocol Internet Protocol TCP IP networks It maps TCP sockets to X 25 virtual circuits and vice versa or to Link Access Procedure Balanced LAPB point to point connection identifiers The Gateway software supports X 25 permanent virtual circuits PVCs and switched virtual circuits SVCs as well as TCP IP over all interface types supported in the Nortel Networks router X 25 Gateway supports e TCP IP over Fiber Distributed Data Interface FDDI Ethernet and token ring LAN media or over X 25 frame relay Asynchronous Transfer Mode ATM and switched multimegabit data service SMDS wide area network WAN or metropolitan area network MAN media e X 25 Levels 2 and 3 over synchronous interfaces 6 MB s and below or Multichannel T1 MCT1 interfaces e 10 VCs per logical channel for the FRE2 040 32MB platform for a total of 240 VCs per slot e 32 VCs per channel for the FRE1 060 64MB for a total of 310 VCs per slot Use Site Manager s Configuration Manager to configure a system for X 25 Gateway services 308649 14 00 Rev 00 1 1 Configuring X 25 Gateway Services X 25 Gateway Topology Figure 1 1 shows a topology
20. EEE O KXKKNKUKNUNUNUNNENENN ON Enable ENABLE 7 Source X 121 Address Destination X 121 Address Destination PYC LCN Remote IP Address Remote TCP Port Number Figure 2 8 IPEX Mapping Table Configuration Window After Replicating a TCP to PVC Connection 308649 14 00 Rev 00 2 17 Configuring X 25 Gateway Services Parameters for Replicating Connections Parameter Default Options Function Instructions MIB Object ID Parameter Default Options Function Instructions MIB Object ID Number of Instances None 1 to 9 for a FRE2 040 32MB platform 1 to 31 for a FRE2 060 64MB platform Specifies the number of connections to be replicated The maximum number of VCs per channel for the FRE2 040 32MB platform is 10 so you can make up to 9 replicates for the FRE1 060 64MB platform the maximum is 32 so you can make up to 31 replicates Enter the number of PVC to TCP or TCP to PVC replicate connections you want to configure Not applicable First LCN number None 2 to 10 for a FRE2 040 32MB platform 2 to 32 for a FRE2 060 64MB platform Identifies the LCN number of the first PVC that will use the replicate configuration Each LCN number on a channel must be unique The options given above assume that you have assigned an LCN number of 1 for the PVC that you are using as the source for replicates Enter the LCN number Not applicable 2 18 308649 14 00 Rev 00 Parameter Default
21. T IS THE ENTIRE AND EXCLUSIVE AGREEMENT BETWEEN NORTEL NETWORKS AND LICENSEE WHICH SUPERSEDES ALL PRIOR ORAL AND WRITTEN AGREEMENTS AND COMMUNICATIONS BETWEEN THE PARTIES PERTAINING TO THE SUBJECT MATTER OF THIS AGREEMENT NO DIFFERENT OR ADDITIONAL TERMS WILL BE ENFORCEABLE AGAINST NORTEL NETWORKS UNLESS NORTEL NETWORKS GIVES ITS EXPRESS WRITTEN CONSENT INCLUDING AN EXPRESS WAIVER OF THE TERMS OF THIS AGREEMENT iv 308649 14 00 Rev 00 Contents Preface pe DT ix TESLU S o ree terrence Hr r EE rr trees x PO E E xi Hard Copy Technical MANUAIS sairas a o aaka xii Fon to Get HEN soba cee waste cael iss dete pr cee cd cme aE o O RE o xii Chapter 1 X 25 Gateway Overview A La Gateway TODO OGY zazss inv prin i o nia dar skon Boli nn er EEE on 1 2 RED EET EV kan 1 3 EEE Me REE rn a O o o oi 1 3 ka Level Z LAPB OM IMENS seeks ket 1 3 TEPPER Saba i k dda 1 4 WEE EE Go DOOR saa r o of EE 1 4 Protocol Trensl 1011 ssoosstars ciaru rulakani k s unov kunda lanka lana 1 4 Establishing Connections from the X 25 Equipment srenrnnrnnrnnvnnnnvnnnnnrrnnnnrnnnennenn 1 6 SVCs with a Called X 121 Address 0 eee oret ka oin EE 1 6 SVCS Without Called X121 Addr ss sccsussrciiiatniend andes 1 7 Permanent Virtual Circuits PVCS ummmmunimmetunmmensmuvi amme nana 1 7 Establishing Connections from the X 25 Level 2 LAPB Terminal anrrnannrnnnennnne 1 8 Establishing Connections During Failure Conditions for PP RS as 1 8 Reesta
22. TI Multichannel T1 interface 1 1 message block 1 13 boundary 1 12 header 1 13 large 1 12 Index 2 message based protocol 1 12 MTU Maximum Transmission Unit 1 12 N network X 25 1 1 network topology TCP IP to LAPB 1 2 TCP IP to X 25 1 2 P Packet Layer Protocol See PLP parameters IPEX Destination Connection Type 2 12 Destination PVC LCN 2 12 Local TCP Port 2 11 Mapping Type 2 5 Remote IP Address 2 10 Remote TCP Port Number 2 11 Source Connection Type 2 4 Source PVC LCN 2 9 TCP Circuit Name 2 6 TCP Header Type 2 6 X 121 Called Address 2 10 permanent virtual circuit See PVC PLP Packet Layer Protocol 1 3 point to point connection 1 1 port TCP 1 4 2 11 product support xii protocol message based X 25 1 12 TCP 1 3 TCP stack 1 11 unstructured stream TCP 1 12 X 25 Level 2 1 3 X 25 Level 3 1 3 X 25 stack 1 11 publications hard copy xii PVC configuring for X 25 Gateway 1 3 definition of 1 1 description of Gateway connection 1 7 308649 14 00 Rev 00 R Remote IP Address parameter 2 10 Remote TCP Port Number parameter 2 11 replicating a configuration 2 12 S socket 1 6 1 7 1 8 source circuit definition of 1 4 Source Connection Type parameter 2 4 Source PVC LCN parameter 2 9 stream protocol TCP 1 12 support Nortel Networks xii SVC configuring for X 25 Gateway 1 3 definition of 1 1 description of Gateway connection 1 6 with called X
23. a or information without first obtaining any required export licenses or other governmental approvals Without limiting the foregoing Licensee on behalf of itself and its subsidiaries and affiliates agrees that it will not without first obtaining all export licenses and approvals required by the U S Government i export re export transfer or divert any such Software or technical data or any direct product thereof to any country to which such exports or re exports are restricted or embargoed under United States export control laws and regulations or to any national or resident of such restricted or embargoed countries or ii provide the Software or related technical data or information to any military end user or for any military end use including the design development or production of any chemical nuclear or biological weapons 9 General If any provision of this Agreement is held to be invalid or unenforceable by a court of competent jurisdiction the remainder of the provisions of this Agreement shall remain in full force and effect This Agreement will be governed by the laws of the state of California Should you have any questions concerning this Agreement contact Nortel Networks 4401 Great America Parkway PO Box 58185 Santa Clara California 95054 8185 LICENSEE ACKNOWLEDGES THAT LICENSEE HAS READ THIS AGREEMENT UNDERSTANDS IT AND AGREES TO BE BOUND BY ITS TERMS AND CONDITIONS LICENSEE FURTHER AGREES THAT THIS AGREEMEN
24. ablish an outgoing connection on the destination circuit In Figure 1 2 the source circuit is the one with the X 25 connection Protocol Translation Figure 1 2 shows the sequence of establishing the translation session when the connection request comes from the X 25 terminal 1 4 308649 14 00 Rev 00 X 25 terminal gt Step 1 connection requested X 25 terminal Za X 25 reguest pending Step 2 X 25 terminal C ME eg X 25 request pending Step 3 X 25 terminal Step 4 O X 25 request accepted Figure 1 2 X 25 gateway router TCP IP l host 3 X 25 gateway router TCP IP host E TCP connection X 25 attempt gateway router TCP IP host 3 7 _ TCP connection X 25 accepted gateway router TCP IP host E gt 4 TCP connection established X250023A X 25 Gateway Overview How X 25 Gateway Establishes a Session X 25 Initiated If the router detects congestion on the receiving side of the network it controls the data flow by queuing the requests on the sending side until the congestion lifts or the connection terminates 308649 14 00 Rev 00 1 5 Configuring X 25 Gateway Services Establishing Connections from the X 25 Equipment Either the X 25 equipment or the TCP IP based system can reque
25. arameters include Source PVC LCN X 121 Called Address Remote IP Address Remote TCP Port Number Local TCP Port Destination Connection Type Destination PVC LCN Click on OK The IPEX Mapping Table Configuration window reopens Click on Done The X 25 Gateway configuration is complete You return to the X 25 Service Configuration window To learn how to replicate this configuration for other PVC TCP connections see the later section of the guide Replicating a Configuration Otherwise click on Done You return to the main Configuration Manager window IPEX Mapping Parameters Windows In the appropriate IPEX Mapping Parameters window define a new mapping entry by specifying source and destination addresses the format of which depend on whether the connection type is PVC SVC or TCP 308649 14 00 Rev 00 2 7 Configuring X 25 Gateway Services Cancel OK Values Help Source PVC LCN Remote IP Address Remote TCP Port Number Figure 2 2 IPEX Mapping Parameters Window for PVC Cancel OK Values Help X 121 Called Address 1234567 Remote IP Address Remote TCP Port Number Figure 2 3 IPEX Mapping Parameters Window for SVC 2 8 308649 14 00 Rev 00 Local TCP Port Enabling X 25 Gateway Cancel OK Values Help 12304 Destination Connection Type Destination PYC LCN Source X 121 Address Destination X
26. blishing the X 25 Connection arsrvnnrnrrnnnnvnnnnnnvnnnnvrnnannvnnenvenannrnnnnnnennenn 1 8 Reestablishing the TOPAP ConneCion vesken noden 1 9 Establishing Connections from the TCP IP H st isiocoviosiiovinkoso o sno k sku kozna van ko 1 9 EEE ENE 1 11 308649 14 00 Rev 00 V Handling Large Dala Messages zis20sa1s3 uda ona na ana 1 Z How X 25 Handles Large Data Messages 1 FRE 119 an ein ieee le How TCP Handles Large Data Messages mmmnnnvnnnnrrnannnvnnnrnrvnnnnvnnannvenrnnrnnnnnneennnn 1 12 X 25 Gateway Message Block Options c ccceseeesceeeeeeeeeeeeeeeeeeeeeeseaeeesaeenneeeates 1 13 Chapter 2 Enabling X 25 Gateway Propam a L ren FIG susisieks A pk eines 2 1 Configuring X 25 IPEX Services 1 107 dikte 1 s sta 15 d 2 1 Enabling 2 25 Gateway S VNE suser r nn 2 2 Adding an Entry to the IPEX Mapping Table cccscceseeeeseeeeeeeeeeeeeeteeeeeeeeteneees 2 2 Cantig rng Mapping Parameters nc ccsscurssarceacsasdedsdetesnsed ease aoia o 2 7 IPEX Mapping Parameters Windows srennnnrnnnnnvnnnnnrvnnnrnnnnnnnennnrrnnnnnvnnnenrrnsnnrnnnennene 2 7 Parameters f r PVC and SVC COMMS CHONS Lumnmmmunummninmemueinnsantniknu 2 9 Parametas far TOP OM NOM8 soisista rano uni no 2 11 Eee zp lo r oo 2 12 Parameters for Replicating Connections ooonoononnnoon none nn 2 18 Index vi 308649 14 00 Rev 00 Figures Figure 1 1 Sample Network Topology Using X 25 Gateway
27. cable 6 Use of Software in the European Community This provision applies to all Software acquired for use within the European Community If Licensee uses the Software within a country in the European Community the Software Directive enacted by the Council of European Communities Directive dated 14 May 1991 will apply to the examination of the Software to facilitate interoperability Licensee agrees to notify Nortel Networks of any such intended examination of the Software and may procure support and assistance from Nortel Networks 7 Term and termination This license is effective until terminated however all of the restrictions with respect to Nortel Networks copyright in the Software and user manuals will cease being effective at the date of expiration of the Nortel Networks copyright those restrictions relating to use and disclosure of Nortel Networks confidential information shall continue in effect Licensee may terminate this license at any time The license will automatically terminate if Licensee fails to comply with any of the terms and conditions of the license Upon termination for any reason Licensee will immediately destroy or return to Nortel Networks the Software user manuals and all copies Nortel Networks is not liable to Licensee for damages in any form solely by reason of the termination of this license 8 Export and Re export Licensee agrees not to export directly or indirectly the Software or related technical dat
28. ctions Destination Connection Type None SVC PVC Specifies either SVC or PVC as the destination connection for this TCP source connection Choose the value that applies to your network 1 3 6 1 4 1 18 3 5 15 2 1 8 Note Either the source or the destination connection type but not both must be TCP Parameter Default Options Function Instructions MIB Object ID Destination PVC LCN None 1 to 4095 Specifies the PVC LCN that you map to the TCP connection The port monitors the X 25 calls for this LCN to initiate the connection This window appears only if you chose PVC as your source connection type Enter the LCN of the PVC for this IPEX connection 1 3 6 1 4 1 18 3 5 15 2 1 11 Replicating a Configuration After you have configured one PVC to TCP or TCP to PVC connection you can copy that configuration and apply it to other connections rather than configuring the mappings one at a time If you need to customize some of the connections you can edit them later Note The Copy function works when one end of a connection is a PVC and the other is TCP It does not work with SVC connections 308649 14 00 Rev 00 Enabling X 25 Gateway Use the Copy button in the IPEX Mapping Table Configuration window Figure 2 5 to replicate a configuration The window is the same for both PVC to TCP and TCP to PVC connections the information the window displays varies according to the configuration
29. cuit Select TCP to specify a Transmission Control Protocol connection MIB Object ID 1 3 6 1 4 18 3 5 15 2 1 4 2 4 308649 14 00 Rev 00 Parameter Default Options Function Instructions MIB Object ID Enabling X 25 Gateway Mapping Type End_to_End Local End_to_End Gateway Specifies whether facilities call user data and M bit and Q bit support terminate locally or are passed end to end X 25 parameters that you configure at the packet and service record level determine which facilities are supported The last option is to configure X 25 Gateway services If you set this parameter to Local IPEX ports can support different packet sizes at each end You must also configure the Source X 121 Address parameter for an SVC source connection type and both Source and Destination X 121 Address parameters for a TCP source connection type If you configure End to End mapping all IPEX ports must have the same packet and window size because different packet sizes cause M bit support to malfunction If you set this parameter to Gateway you use X 25 Gateway services X 25 terminates at the router interface but allows you to configure one of three message header types at the TCP application layer Choose Gateway 1 3 6 1 4 1 18 3 5 15 2 1 16 308649 14 00 Rev 00 2 5 Configuring X 25 Gateway Services Parameter Default Options Function Instructions Parameter Default Options Functio
30. e is a corresponding TCP connection set up between X 25 Gateway and the TCP IP peer This connection remains established until either e The X 25 equipment resets the PVC connection e The X 25 interface is restarted The TCP peer terminates the TCP connection The mapping information that you must configure is e The circuit interface for the PVC connection e The logical channel number LCN of the PVC connection e The associated remote TCP socket IP address and TCP port number that identifies the remote end of the TCP connection 308649 14 00 Rev 00 1 7 Configuring X 25 Gateway Services Establishing Connections from the X 25 Level 2 LAPB Terminal The router uses a similar procedure for establishing LAPB to TCP connections You must specify the mapping information needed to configure the connection specifically The circuit interface through which X 25 Gateway will establish a LAPB connection e Its associated remote TCP socket which identifies the remote end of the TCP connection This mapping information sets up the path for forwarding data traffic received in a LAPB circuit to a specific remote TCP IP server and for forwarding data traffic received from a TCP connection to a specific LAPB circuit When it has established this LAPB to TCP translation session X 25 Gateway translates the LAPB information frames it receives from the LAPB terminals into TCP data segments and vice versa Establishing Connections Du
31. e type of connection SVC or PVC at the X 25 end of the connection e The logical channel number LCN of the PVC connection or the pair of calling and called X 121 addresses of the SVC connection 1 10 308649 14 00 Rev 00 X 25 Gateway Overview After establishing this X 25 to TCP session X 25 Gateway translates X 25 Level 3 data packets received from the X 25 client terminals to TCP data segments and vice versa Connection Summary To set up a reliable X 25 Gateway session both sides must successfully establish the connections When one side receives a connection indication the other side initiates a connection attempt If the connection attempt fails on the far side the near side rejects the connection request it received Figure 1 6 shows how X 25 Gateway mediates the interaction between the two protocol stacks as the data flows between the X 25 client terminals and the TCP based hosts Information from to other Information TCP hosts from to other or other Gateway X 25 terminals routers IL X 25 Gateway oO N gt gt Te LO a N x x lt IEEE 802 2 IE X 25 level 3 n IP u sle SNMP X 25 level 2 EE IEEE 802 2 O Lu Lu u 4 V 35 IEEE 802 3 l X250013B Figure 1 6 Role of the X 25 and TCP Protocol Stacks in X 25 Gateway 308649 14 00 Rev 00 1 11 Configuring X 25 Gateway Services The
32. ed within one or in several data segments When X 25 Gateway receives the X 25 user data and translates it to a TCP data segment the message boundary is lost To minimize changes in the existing host applications X 25 Gateway maintains the X 25 message boundary It structures the application information into message blocks before encapsulating it in TCP data segments Each message block contains a header and a data portion 308649 14 00 Rev 00 X 25 Gateway Overview X 25 Gateway Message Block Options You can configure X 25 Gateway with the following message block options No message block structure in any TCP segment X 25 Gateway translates each TCP data segment as a complete message e Message length specified The header portion of the message contains a 2 byte message length field The data portion holds the actual application information The length field indicates the total length of the application data portion in the message block e Message version type and length specified in the header The header specifies the version of the message header format including a More flag bit The Type field specifies the message type DATA The data portion holds the actual application information The message block options that let you specify the message length allow TCP clients to determine message boundaries Depending on the size of the message block a TCP data segment can contain multiple message blocks A larger message
33. has been damaged as a result of accident misuse or abuse The Licensee assumes all responsibility for selection of the Software to achieve Licensee s intended results and for the installation use and results obtained from the Software Nortel Networks does not warrant a that the functions contained in the software will meet the Licensee s requirements b that the Software will operate in the hardware or software combinations that the Licensee may select c that the operation of the Software will be uninterrupted or error free or d that all defects in the operation of the Software will be corrected Nortel Networks is not obligated to remedy any Software defect that cannot be reproduced with the latest Software release These warranties do not apply to the Software if it has been i altered except by Nortel Networks or in accordance with its instructions ii used in conjunction with another vendor s product resulting in the defect or iii damaged by improper environment abuse misuse accident or negligence THE FOREGOING WARRANTIES AND LIMITATIONS ARE EXCLUSIVE REMEDIES AND ARE IN LIEU OF ALL OTHER WARRANTIES EXPRESS OR IMPLIED INCLUDING WITHOUT LIMITATION ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE Licensee is responsible 308649 14 00 Rev 00 iii for the security of its own data and information and for maintaining adequate procedures apart from the Software to reconstruct lost or altered files data or pr
34. identifies the IP option on the Protocols menu vertical line Separates choices for command keywords and arguments Enter only one of the choices Do not type the vertical line when entering the command Example If the command syntax 1s show ip alerts routes you enter either show ip alerts or show ip routes but not both x 308649 14 00 Rev 00 Acronyms CCITT DCE DDN DTE FDDI IP IPEX ITU T LAN LAPB LCN MAN MIB MCTI1 MTU PDN PLP PPP PToP PVC SNMP SVC TCP TCP IP Telnet Preface International Telegraph and Telephone Consultative Committee now ITU T data circuit terminating equipment Defense Data Network data terminal equipment Fiber Distributed Data Interface Internet Protocol IP Encapsulation of X 25 International Telecommunications Union Telecommunications formerly CCITT local area network Link Access Procedure Balanced logical channel number metropolitan area network Management Information Base Multichannel T1 maximum transmission unit Public Data Network Packet Layer Protocol Point to Point Protocol Point to Point Nortel Networks proprietary permanent virtual circuit Simple Network Management Protocol switched virtual circuit Transmission Control Protocol Transmission Control Protocol Internet Protocol Telecommunication Network 308649 14 00 Rev 00 xi Configuring X 25 Gateway Services TFTP Trivial File Transfer Protocol WAN wide area
35. n Instructions MIB Object ID TCP Circuit Name None The name of this circuit When you add a TCP circuit the name is displayed in the Add Circuit window Identifies this TCP circuit for mapping purposes Enter the name of the appropriate TCP circuit If you do not know this name return to the main Configuration Manager window and click on the connector you are configuring to reopen the Add Circuit window TCP Header Type Short None Short Long Enables the Message Boundary Protocol This bit marks the boundary of TCP application data that is consistent with Gateway operation None means that there is no message header Message Boundary Protocol is off Short means that the message header contains a 2 byte length field Long means that the message header contains a 1 byte type a 1 byte version and a 2 byte length field Choose a header type 1 3 6 1 4 1 18 3 5 15 2 1 22 2 6 308649 14 00 Rev 00 Configuring Mapping Parameters Enabling X 25 Gateway Complete the following steps to configure IPEX mapping parameters Site Manager Procedure You do this System responds 1 In the IPEX Mapping Add window click on OK The IPEX Mapping Parameters window opens Depending on your Source Connection Type Figure 2 2 Figure 2 3 or Figure 2 4 opens Configure the parameters appropriate to your connection type Click on Help or see the parameter descriptions beginning on page 2 9 P
36. n to the destination You configure this parameter only when the source connection type is SVC Enter the IP address of the remote connection Use dotted decimal notation for example 1 1 1 1 Consult your network administrator for the correct value 1 3 6 1 4 1 18 3 5 15 2 1 12 2 10 308649 14 00 Rev 00 Enabling X 25 Gateway Parameter Default Options Function Instructions MIB Object ID Remote TCP Port Number None The TCP port number at the remote connection a value between 12304 and 16399 Specifies the remote TCP port number used to establish a TCP connection to the destination The remote TCP port originates connections to the local TCP port You configure this parameter only when the source connection type is SVC Enter the TCP port number for the remote connection 1 3 6 1 4 1 18 3 5 15 2 1 13 Parameters for TCP Connections Parameter descriptions for TCP connections follow Parameter Default Options Function Instructions MIB Object ID Local TCP Port None The local TCP port number a value between 12304 and 16399 Specifies the TCP port in the local IPEX connection This port accepts inbound TCP connections from the remote TCP port You configure this parameter when the Source Connection Type is TCP Enter the TCP port number 1 3 6 1 4 18 3 5 15 2 1 5 308649 14 00 Rev 00 Configuring X 25 Gateway Services Parameter Default Options Function Instru
37. ograms 4 Limitation of liability IN NO EVENT WILL NORTEL NETWORKS OR ITS LICENSORS BE LIABLE FOR ANY COST OF SUBSTITUTE PROCUREMENT SPECIAL INDIRECT INCIDENTAL OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES RESULTING FROM INACCURATE OR LOST DATA OR LOSS OF USE OR PROFITS ARISING OUT OF OR IN CONNECTION WITH THE PERFORMANCE OF THE SOFTWARE EVEN IF NORTEL NETWORKS HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES IN NO EVENT SHALL THE LIABILITY OF NORTEL NETWORKS RELATING TO THE SOFTWARE OR THIS AGREEMENT EXCEED THE PRICE PAID TO NORTEL NETWORKS FOR THE SOFTWARE LICENSE 5 Government Licensees This provision applies to all Software and documentation acquired directly or indirectly by or on behalf of the United States Government The Software and documentation are commercial products licensed on the open market at market prices and were developed entirely at private expense and without the use of any U S Government funds The license to the U S Government is granted only with restricted rights and use duplication or disclosure by the U S Government is subject to the restrictions set forth in subparagraph c 1 of the Commercial Computer Software Restricted Rights clause of FAR 52 227 19 and the limitations set out in this license for civilian agencies and subparagraph c 1 ii of the Rights in Technical Data and Computer Software clause of DFARS 252 227 7013 for agencies of the Department of Defense or their successors whichever is appli
38. orrespond to the X 25 called address This correspondence is the mapping information that you must configure for X 25 to TCP conversion The mapping information consists of e The point of attachment that is the circuit interface on the Gateway system at which the SVC establishes the connection e The X 25 called address of the incoming connection e The associated remote TCP socket IP address and TCP port number that identifies the remote end of the TCP connection 308649 14 00 Rev 00 X 25 Gateway Overview SVCs Without a Called X 121 Address When the X 25 SVC connection does not contain an X 121 called address in the incoming call request packet you specify the SVC service on that circuit to be a special SVC service interface by configuring e The circuit interface in X 25 Gateway at which the SVC establishes the connection e The SVC service interface on that circuit which is special in that it must be set up as a data terminal equipment DTE interface instead of as a data circuit terminating equipment DCE interface e The associated remote TCP socket remote IP address and TCP port number that identifies the remote end of the TCP connection The router uses this information to form a translation session by accepting this connection and establishing an associated TCP connection Permanent Virtual Circuits PVCs For each permanent virtual circuit connection between the X 25 system and X 25 Gateway ther
39. ponds 10 Set the following parameters Click on Help or see the parameter descriptions beginning on page 2 4 Source Connection Type Mapping Type TCP Circuit Name TCP Header Type Service VC Type Window Size Packet Size 8 Click on OK The IPEX Mapping Table Configuration window opens 9 Click on Add The IPEX Mapping Add window opens Figure 2 1 308649 14 00 Rev 00 Configuring X 25 Gateway Services Cancel OK Values Help Source Connection Type PYC Mapping Type GATEWAY TCP Circuit Name MCT1 21 1 TCP Header Type HORT Figure 2 1 IPEX Mapping Add Window for Source PVC Note This window is the same for PVC SVC and TCP source connections The Mapping Type is always Gateway Values for the other parameters are specific to your network Parameter Source Connection Type Default None Options PVC SVC TCP Function Specifies the type of connection at the sending end of the original message PVC and SVC specify an X 25 Level 3 connection either a permanent virtual circuit or a switched virtual circuit TCP is a Transmission Control Protocol connection Source connection types PVC and SVC send to destination connection type TCP Source connection type TCP sends to destination connection type PVC or SVC Instructions Select PVC to specify an X 25 connection to a permanent virtual circuit Select SVC to specify an X 25 connection to a switched virtual cir
40. pport With this configuration the router translates data received from LAPB connections to TCP data packets and forwards those packets out through TCP connections It also translates data received from TCP connections to LAPB data and forwards the data out through LAPB connections 1 2 308649 14 00 Rev 00 X 25 Gateway Overview Network Interfaces Nortel Networks routers that support X 25 Gateway services use the following protocols e X 25 Level 3 Packet Layer Protocol PLP e X 25 Level 2 Protocol LAPB e Transmission Control Protocol TCP X 25 Level 3 PLP Interface On an X 25 Level 3 interface you can create and configure multiple virtual circuits including e Permanent virtual circuits e Switched virtual circuits with or without called X 121 addresses You can create a set of either of these connections or a combination of the two On any X 25 interface you can configure either X 25 Gateway service or other types of X 25 services such as Public Data Network PDN Point to Point PtoP and Defense Data Network DDN If you configure X 25 Gateway service on an X 25 interface the software translates data sent and received between the X 25 network interface and the TCP IP network interface It uses X 25 flow control mechanisms to detect congestion in the X 25 connection X 25 Gateway uses the X 25 Level 3 client interface to e Open and close X 25 connections e Send data to the X 25 module for transmission
41. ring Failure Conditions for PVC TCP Translation The X 25 Gateway software running on X 25 PVC devices is able to reestablish a connection when a fault occurs at the TCP IP or X 25 physical layer You do not have to enable or configure this feature The figures below show how the software reestablishes a connection between X 25 and TCP IP Reestablishing the X 25 Connection When a physical layer fault occurs a disconnected cable at the X 25 interface Figure 1 3 X 25 Gateway disconnects the associated TCP connections It reestablishes the TCP connections to the mapped X 25 virtual circuits when the X 25 interface is again available 1 8 308649 14 00 Rev 00 X 25 Gateway Overview X 25 TCP IP gateway host router X 25 me 4 terminal KD TCP X 25 connections interface 3 reset down X250024A Figure 1 3 Reestablishing X 25 Connections Reestablishing the TCP IP Connection In the event of a physical layer fault on the TCP IP interface Figure 1 4 X 25 Gateway resets any established TCP connections as well as the X 25 connections associated with each TCP connection The software attempts to reestablish a TCP connection until the TCP interface is again available When TCP connections are available the software resets the X 25 connections to an operational state Examples of physical layer faults include a disconnected cable or a failure at either the X 2
42. rom a LAPB terminal 1 8 from a TCP IP terminal 1 9 from an X 25 terminal 1 6 LAPB to TCP 1 8 summary 1 11 conventions text x copying a configuration 2 12 customer support xii 308649 14 00 Rev 00 Index D DCE interface 1 7 destination circuit definition of 1 4 Destination Connection Type parameter 2 12 Destination PVC LCN parameter 2 12 DTE interface 1 7 E Ethernet 1 1 F fault physical layer 1 8 FDDI 1 1 flow control 1 3 G Gateway definition of 1 1 H header message 1 13 l interface circuit 1 6 DCE 1 7 DTE 1 7 TCP 1 4 Index 1 IP Internet Protocol address 1 4 IPEX adding a mapping entry 2 2 mapping parameters configuring 2 7 reguirement to configure 2 1 IPEX Mapping Add window 2 4 IPEX Mapping Parameters window PVC 2 8 SVC 2 8 TCP 2 9 IPEX Mapping Replication Window 2 15 IPEX Mapping Table Configuration Window 2 13 IPEX Mapping Table Configuration Window After Replication PVC to TCP Connection 2 16 TCP to PVC Connection 2 17 L LAN media 1 1 LAPB Link Access Procedure Balanced connection to TCP 1 8 description of 1 2 1 3 point to point connection 1 1 protocol 1 3 large data message 1 12 LCN logical channel number 1 7 Level 3 Packet Layer Protocol 1 3 Local TCP Port parameter 2 11 MAN metropolitan area network media 1 1 mapping 1 8 1 10 Mapping Type parameter 2 5 Maximum Transmission Unit MTU 1 12 MC
43. st a connection The software relies on a set of configured mapping parameters to associate the X 25 connection on one side of the router to the TCP connection on the other side In response to a connection request from the X 25 equipment the router establishes a connection to a TCP IP server When this TCP connection is established the router accepts the X 25 connection attempt This one to one connection mapping creates a consistent and reliable Gateway session The types of X 25 connections that X 25 Gateway supports include e Switched virtual circuits SVCs e Switched virtual circuits with no X 121 called address e Permanent virtual circuits PVCs With an X 25 Level 3 interface you can establish a switched virtual circuit or a permanent virtual circuit between the X 25 equipment and the TCP based system An SVC is a temporary logical connection It may or may not have a called address associated with it depending on whether the type of connection that you configured required an X 121 called address The following sections describe what you configure for each of these connections SVCs with a Called X 121 Address To establish an SVC connection that contains a specified X 25 called address X 121 address you configure mapping information that X 25 Gateway uses to set a path for forwarding data traffic received on an X 25 SVC to a specific remote TCP IP peer The remote TCP IP peer has an IP address and TCP port number that c
44. start and customize X 25 Gateway services on a Nortel Networks router Before You Begin Before using this guide you must complete the following procedures For a new router e Install the router refer to the installation manual that came with your router e Connect the router to the network and create a pilot configuration file refer to Quick Starting Routers Configuring BayStack Remote Access or Connecting ASN Routers to a Network Make sure that you are running the latest version of Nortel Networks BayRS and Site Manager software For information about upgrading BayRS and Site Manager see the upgrading guide for your version of BayRS 308649 14 00 Rev 00 ix Configuring X 25 Gateway Services Text Conventions This guide uses the following text conventions bold text Indicates text that you need to enter and command names and options Example Enter show ip alerts routes Example Use the dinfo command italic text Indicates file and directory names new terms book titles and variables in command syntax descriptions Where a variable is two or more words the words are connected by an underscore Example If the command syntax is show at lt valid_route gt valid_route is one variable and you substitute one value for it screen text Indicates system output for example prompts and system messages Example set Trap Monitor Filters separator gt Shows menu paths Example Protocols gt IP
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