ENET-AP001D-EN-P, EtherNet/IP Performance Application Solution
Contents
1. 3 7 TCPand CIP IIIA ee ata ES 3 8 TCP IP Stack timeout not user configurable 3 8 Gl Sie sul SA Paneer RE wo ee A ea me ea reer ena 3 8 Multicast Brames misia canines Su eee a edhe antl etnies 3 9 Multicast address limit 3 10 Publication ENET AP001D EN P October 2004 Table of Contents 2 Predict System Performance Worksheets Publication ENET AP001D EN P October 2004 Chapter 4 THEO AUCH Ai wed a SRS UA AA RE Re ag AC 4 1 System Prediction Goals gay enka veh bade ree aa nae eed 4 1 Part I Determine if the system has sufficient bandwidth to fulfill the requirements of the application 4 2 Part II Predict the maximum input or output times for CIP connections III WEI 4 3 Performance Caletlationsy ii IIIA 4 3 Identify and count connections 4 4 Calculate packets second 4 4 Estimate the fastest RPI 0 ccc ANA 4 6 Estimate maximum input or output times for CIP connections 4 7 Example Predict System Performance 4 7 Part I Determine if the system has sufficient bandwidth to fulfill the requirements of the application 4 8 Explicit EA AAA 4 8 EtherNet IP modules serving as adapters 4 9 EtherNet IP modules 2 and 3 with consumed tags 4 10 EtherNet IP module serving as a scanner 4 12. Knowledgebase articles 1 3 L limits CIP connected messages 3 5 CIP connection timeouts 3 8 CIP unconnected messages 3 7 multicast addresses 3 10 TCP onnections 3 3 TCP IP stack timeouts 3 8 Publication ENET AP001D EN P October 2004 2 Index messages CIP connections 3 4 explicit 4 1 4 8 implicit 4 1 multicast addresses 3 10 multicast frames 3 9 0 ODVA 1 3 overview 1 1 P performance calculations 4 3 plan connections 3 1 network 1 2 switches 2 1 port mirroring 2 2 producer 3 2 reference materials 1 3 RPI times 4 6 S server 3 2 SNMP 2 3 switches autonegotiation 2 3 full duplex 2 1 functionality 2 1 IGMP snooping 2 2 plan 2 1 port mirroring 2 2 recommended features 2 1 required features 2 1 VLAN 2 3 wire speed switching fabric 2 3 Publication ENET AP001D EN P October 2004 switching SNMP 2 3 system performance achieve more throughput 4 12 calculate delays for CIP connections 4 16 calculate packets second 4 4 calculate times for CIP connections 4 16 calculations 4 3 determine bandwidth 4 2 example 4 7 fastest RPI 4 6 predict times for CIP connections 4 3 4 7 worksheets A 1 T TCP limits 3 3 TCP IP connections 3 1 3 3 encapsulation 1 1 timeouts 3 8 timeouts 3 8 transports 3 2 U UCMM 3 2 unconnected messages 3 7 user manuals 1 3 V VLAN 2 3 W wire speed switching fabric switching fabric 2 3 worksheets A 1 How Are We Doing AB Your comments on our te
3. N A Total Packets Second 220 The total of 220 packets second is well within the remaining bandwidth for these modules 4500 pps limit for a 1756 ENBT module 810 pps limit for a 1756 ENET B module Publication ENET AP001D EN P October 2004 4 10 Predict System Performance EtherNet IP modules 2 and 3 with consumed tags EtherNet IP modules 2 and 3 interface two consumer controllers to the network Each of these controllers consumes one produced tag at an RPI of 20 ms For either of these EtherNet IP modules Produced Tag Connections _ 0 Packets Second 1 connections RPI for each produced tag N A Consumed Tags 1 tag 20 ms Packets Second 2 RPI for each consumed tag 2 20 ms 100 Total Packets Second 100 The total of 100 packets second is well within the remaining bandwidth for these modules 4500 pps limit for a 1756 ENBT module 810 pps limit for a 1756 ENET B module Publication ENET AP001D EN P October 2004 EtherNet IP module serv Predict System Performance 4 11 ing as a scanner EtherNet IP module 1 in the chassis with the main controller is the most loaded EtherNet IP module racks the Panel View and the It must communicate with the five specified I O two other controllers using a produced tag It must perform explicit messaging as well Assume the PanelView is a direct connection at an RPI of 100 ms There are also 5 rack optimized connec t
4. RPI transmission switch queue 0 25ms 20ms 0 01ms x connections through this module 0 1ms 1 1ms x connections through this module 0 25ms 20ms 0 01 x 11 ms 0 1ms 1 1ms x 11 0 25ms 20ms 0 11ms 0 1ms 12 1ms 32 56ms The queuing delay uses a multiplier of 1 1ms because the 1756 ENET B module supports only 900 pps This means that a single packet takes 1 900 second 1 1ms to process If the example used a 1756 ENBT module which supports 5000 pps the multiplier would be 1 5000 seconds 0 2ms Conclusion For this example interface 1A has an RPI 20ms that is only 2 times larger than the queuing delay 12 1ms This means that the RPI value does not dominate the equation and the RPI value will be a poor estimate of the total input delay The rough estimate for a rack optimized connection see page 4 16 was 20ms RPI But the refined calculation is significantly larger mainly because of the queuing delay You could reduce the queueing delay by using a 1756 ENBT module instead of the 1756 ENET B module EtherNet IP Module Packets Second Worksheets Appendix A Rack Optimized Connections Packets Second 2 x connections RPI Direct Connections Packets Second 2 x connections RPI Produced Tag Connections Packets Second 1 connections RPI for each produced tag Consumed Tags Total Packets Second EtherNet IP Module ID Packets Second
5. 1 100 ms PanelView Packets Second 2 x connections RPI 2 x 1 100 ms 20 Direct Connections _6 50 ms for I O Packets Second 2 x connections RPI 2x 6 50 ms 240 Produced Tag Connections _2 20 ms Packets Second 1 connections RPI for each produced tag 1 2 20 ms 150 Consumed Tags 0 Packets Second 2 RPI for each consumed tag N A Total Packets Second 610 EtherNet IP interface 1A has a total of 11 implicit connections The total of 610 packets second is well within the bandwidth for 1756 ENET B module 1A 810 pps limit for a 1756 ENET B module Publication ENET AP001D EN P October 2004 Predict System Performance 4 15 1756 ENBT module 1B has three rack optimized connections to the Adapter_6 Adapter 7 and Adapter_8 modules at RPIs of 20 ms It also has nine direct connections to analog modules in racks 6 8 at RPIs of 50 ms It has no produced or consumed tags Por 1756 ENBT module 1B calculate the following EtherNet IP Module ID _ 1B Rack Optimized Connections _3 20 ms for I O Packets Second 2 x connections RPI 2x 3 20 ms 300 Direct Connections _9 50 ms for I O Packets Second 2 x connections RPI 2x 9 50 ms 360 Produced Tag Connections __0 Packets Second 1 connections RPI for each produced tag N A Consumed Tags 0 Packets Second 2 RPI for each consumed tag N A EtherNet IP interface
6. 1B has a total of 12 implicit connections The total of 660 packets second is well within the bandwidth for 1756 ENBT module 1B 4500 pps limit for a 1756 ENBT module Conclusion The redesigned system now has sufficient bandwidth for the application This concludes the first goal of performance predictions determining if the system can fulfill the application s requirements Next determine the maximum input output and produced tag times for the system Then you can determine if these are acceptable for the application Publication ENET AP001D EN P October 2004 4 16 Publication ENET AP001D EN P October 2004 Predict System Performance Part Il Estimate the maximum input or output times for CIP connections Calculate the worst case maximum input I O to controller or output controller to I O times for CIP connections in our system For a Rack Optimized Connection the maximum input or output time for a CIP connections is estimated as TMAX Rack Optimized RPI 20ms For the Direct Connect Analog Modules assume non isolated modules with the real time sampling RTS rate equal to the RPI i e 50 ms Therefore the maximum input or output time is estimated as TMAX Analog Non Isolated 7 2RTS 2 x 50 ms 100 ms Isolated modules have an RTS rate of 1RTS For a Produced or Consumed Tag the maximum input or output time is estimated as TMAX Produced Consumed Tag 7 IRPI 1 x 20 ms 20 ms Assume t
7. 2 RPI for each consumed tag Publication ENET AP001D EN P October 2004 Worksheets A 2 PU0O2238 S19H92J 18101 Se pdwnsuod y JO IJA t puosas slaxspeg SS2 1 pownsuoy Se poonposd yova IOj Id suonseuu0s J puodag saypug suoNJJaUUO 321 psonpolg Id suonseuu0s 7 puodag s oyDeg SUOTIN9IUUOZ PAA Id suonseuu0s x 7 puosag s oyDeg suono uuo pazilundo Joy AI MP dI 9NP WA PU02238 S19H92J 1101 Se pawnsuod ya 10 GY Z puodag sjoxpeg S3521 pownsuoy Se poonposd yova 10 IMY Cuonsauuos J puodag sjaypeg suONd9UU07 SET posonpolg Id suonssuuo0s x 7 puodag s 949e SUOTID9IUUOZ PAA Id suonssuuo0s x 7 puodag s o49e suondJauu09 pazilundo Hey 1 POMPON dI 9NP WA Publication ENET AP001D EN P October 2004 A 3 Worksheets Lie pawnsuo0 j paanpold KUNI SLJ pownsuop 10 psonpolg payejos Bojeuy XVN Idaz SLU z Pasun Bojeuy XVN j 2U01 99UU0Z PANA id z poz wgdo 4984 XYIN uonJJauu09 pozru do Ly Adeinaay 00L ewbis 104 Iduz pawnsuo psanpold XVN 3L 1 pournsuoy JO paonpoJg Idd SIM parelos Bojeuy XYI dU SLY z PaeIOsI uON Boreuy XVN SU0TJD9UUOZ PNA IRIT paziwndo 4984 XYIN 7U0T D9UUOZ pozrwndo ry AJeinaay 66 BWBIS Z 404 SUOIJIOUUO4 di9 10 SOW 0 1 0 49 01 U04 ndynQ 10 18 01 U04 0 0 1 Indu wnwixeN Publicat
8. I O adapter see chapter 3 additional information on how the RPI translates into the actual packet interval see page 4 5 Publication ENET AP001D EN P October 2004 Summary of Changes 2 Notes Publication ENET AP001D EN P October 2004 EtherNet IP Overview Select an Ethernet Switch How Connections and Multicast Frames Affect Data Transfer Table of Contents Chapter1 Introduction AA 1 1 EtherNet IP Overview 1 1 Planning an EtherNet IP Netwotk 1 2 Additional Reference Materials 1 3 Chapter 2 IA EIA aaa 2 1 Switch Functionality for EtherNet IP Systems 2 1 Full Duplex Capability on all Ports 2 1 IGMP SOO PIIO cue se WA Gein Ge 2 2 Port Mitron 2 cpt so Bas tet Ghent oS gts eee ar ANA Stn candela daa 2 2 VLAN Virtual Local Area Netwotk 2 3 MULONGO HAO sas gi Ra RSS AES SG HORM Raa ete S 2 3 Wire Speed Switching Fabric 2 3 SNMP Simple Network Management Protocol 2 3 Chapter 3 Introduction s aene II eet T E AE AE E OTKA T 3 1 Connection Iverview UWA IAA EE PR 3 1 Terminologi ioien a Ea EE AA S EETA 3 2 TCP HE US AAA 3 3 TCP connection limits 3 3 CIP COUNCCHONS ge ae aaah TAANE Wa 3 4 CIP connected messaging limits 3 5 CIP unconnected messaging limits
9. I O connection to a rack of Flex 1 0 a connection is configured in RSLogix 5000 software by adding the Flex adapter and 1 0 modules in the 1 0 list When the connection is created output packets flow from the controller to the 1 0 rack In addition input packets flow from the 1 0 to the controller Each direction of flow is a transport In this example two transports exist One transport is from the controller to the adapter The second transport is from the adapter to the controller Example 2 Produced Tag For a produced tag connection with 2 consumers there is a connection to each consumer Data from the producer is produced to the wire on one transport Each of the consumers returns a heartbeat A total of 3 transports exist in this example One transport is from the tag producing controller to the wire media The second transport is from one consumer to the tag producer The third transport is from the second consumer UCMM Publication ENET AP001D EN P October 2004 In the web servers you can see references to Unconnected Message Manager UCMM This type of messaging is momentary and therefore can be ignored unless you are troubleshooting Examples of where UCMM messages are used are e Flash update of module firmware e Some functions in RSLinx e CIP Generic MSG instruction e Opening any CIP connection forward_open command How Connections and Multicast Frames Affect Data Transfer 3 3 TCP Connect
10. an implicit connection 1756 ENET B Each module h e Maxim connec e Maxim In addition to the as um um a maximum of 160 CIP connections of which of 128 bridged connections any combination of implicit and explicit tions of 32 end node connections CIP connections the 1756 ENET B supports e Maximum of 16 controllers that can have a rack optimized connection to the module e Maximum of 16 controllers that can have a rack optimized listen only connection to the module e Maximum of 32 controllers can consume data from an implicit connection 1756 EWEB Each module has a maximum of 128 CIP connections of which e Maximum of 128 bridged connections explicit connections e Maximum of 32 end node connections 1769 L32E Each module has a maximum of 32 CIP connections of which 1769 L35E e Maximum of 32 bridged connections any combination of implicit and explicit connections e Maximum of 20 end node connections In addition to the e Maxim um CIP connections the 1769 L32E L35E supports of 32 controllers can consume data from an implicit connection Publication ENET AP001D EN P October 2004 3 6 How Connections and Multicast Frames Affect Data Transfer Product CIP Connected Messaging Limits 1788 ENBT Each module has a maximum of 32 CIP connections of which e Maximum of 32 bridged connections any combination of implicit and explicit connections e Maximum of 20
11. is a point to point communication mechanism used to transfer data between a transmitter and a receiver Connections can be logical or physical An EtherNet IP CIP connection transfers data from an application running on one end node to an application running on another end node A CIP connection is established over a TCP connection A single TCP connection can support multiple CIP connections Example 1 I O Connections A Logix controller has 5 CIP I O connections to modules in remote chassis and all of these connections are through the same local 1756 ENBT and the same remote 1756 ENBT The following connections would exist e 1 TCP connection e 5 CIP connections Example 2 RSLinx OPC Test Client e 1 TCP connection e 4 CIP connections 4 is the default TCP connections are used for all communications on EtherNet IP Even with implicit connections a TCP connection is used and remains open A TCP connection is required for all CIP messaging including connected and unconnected messaging CIP connections are almost always used Unconnected CIP messages are used but are temporary short lived Publication ENET AP001D EN P October 2004 3 2 How Connections and Multicast Frames Affect Data Transfer Term implicit connection Terminology Definition An implicit connections are time critical in nature This includes 1 0 and produced consumed tags Implicit refers to information source address data type destination addr
12. of CIP connections switch Switch latency is the delay between reception of the first bit and transmission of the first bit This delay depends on the type of switch It is typically 0 1 ms switch delay 0 1 ms queue Input data is sent from the remote rack adapter through a switch through a communication module in the controller rack and finally to a controller scanner If two or more input CIP connections are simultaneously ready to be transmitted they must be transmitted sequentially It takes 0 2 ms for a 1756 ENBT to process 1 implicit packet Note that 0 2 ms is equal to the reciprocal of 5000 pps The total queue delay is 0 2ms times the number of CIP connections through the module queue delay 0 2 ms X number of CIP connections For the Direct Connect Analog Modules you add the same transmission switch and queue delays as for rack optimized data TMAX Analog Non Isolated 2RTS transmission switch queue For a Produced or Consumed Tag you add the same transmission switch and queue delays as for rack optimized data TMAX Produced Consumed Tag IRPI transmission switch queue Publication ENET AP001D EN P October 2004 4 18 Predict System Performance Publication ENET AP001D EN P October 2004 Refine the example times for EtherNet IP interface 1A For the example system with 1756 ENET B interface 1A page 4 12 the refined calculation including delays is T Flex input filter
13. this chapter to calculate the packets second loading on each EtherNet IP module and the available bandwidth for any unspecified RPIs Based on the results of these calculations decide if your system will work If necessary modify your system by doing one or more of the following e Increase some RPIs to allow other RPIs in the system to decrease e Change connection types e g direct to rack optimized e Change I O module configurations filter times trigger types e Add EtherNet IP modules e Add Logix controllers e Verify that the network infrastructure can handle the system traffic e Verify that the switches support full duplex operation and IGMP snooping Port mirroring is also important for switch and system diagnostic functions If you have made modifications verify that the modified system will work by re counting the connections and re calculating the packets second loading Predict System Performance 4 3 Part Il Predict the maximum input or output times for CIP connections A CIP connection is an efficient communications path used for high performance Basic types are rack data produce tag Also a CIP connection is bi directional which means that during every RPI interval a packet of information is initiated from both ends of each connection The type of data packet produced by each end of the connection depends on the connection type and is detailed below Connection Type Scanner A
14. verify connectivity inactivity 5 minutes This timer continues to run if CIP connected or unconnected messages are not occurring When this timer expires the TCP stack will e tear down a connection e not attempt to reestablish a connection the controller must do this ARP variable Approximate Timeout implicit message network multiplier x RPI The Address Resolution Protocol ARP timer is used when a device needs to send an IP message to another device ARP allows the sending device to translate a device s IP address to the corresponding MAC ID so that the message can be sent over the EtherNet IP network ARP is used in all TCP IP implementations even your PC An ARP cache temporarily stores mappings of IP addresses to MAC IDs For example e MAC ID e g 0000bc060102 e IP address e g 130 151 139 121 If you replace a Rockwell Automation EtherNet IP module with a new module the new module will have a different MAC ID The ARP cache entries in other devices are now invalid because the MAC ID corresponding to the module s IP address has changed This could cause a delay in reestablishing communications with the replacement module The delay varies depending on the module and the network configuration in use When a Rockwell Automation EtherNet IP starts up it issues a gratuitous ARP which causes other devices to update their ARP caches This generally results in a quick recovery of communications with the replacem
15. 0 This includes rack optimized connections direct connections and messages using produced tags The performance predictions have two major goals e To determine if the system as a whole has sufficient bandwidth to fulfill the requirements of the application e To estimate the maximum input or output times for rack optimized connections direct connections and produced consumed tags Publication ENET AP001D EN P October 2004 4 2 Publication ENET AP001D EN P October 2004 Predict System Performance Part I 7 Start Draw Your System y Identify amp Count Connections f Calculate Packets Second Part Il Estimate Max Times Go to Part II Part Determine if the system has sufficient bandwidth to fulfill the requirements of the application To determine if your system has sufficient bandwidth to fulfill the requirements of the application perform the following steps 1 Draw an overall sketch of your system that includes all processors EtherNet IP modules and I O modules and shows all connections to the network Include a description of what the processors are doing e g messaging using produced tags and any known RPI requirements Identify and count each type of implicit connection for the system and each EtherNet IP module Use the formulas shown later in
16. 1 Recommendations to achieve more throughput with an existing T756 ENET B module ei a yan kh eat KA ts ne 4 12 ONES AA ee Oe eagan ap ee ii 4 15 Part II Estimate the maximum input or output times for GIP COMME CH ONS AI IA 4 16 RefineseStiimates III eRe RRA oe aS 4 16 Refine the example times for EtherNet IP interface 1A 4 18 Appendix A EtherNet IP Module Packets Second A 1 Maximum Input I O to Controller or Output Controller to I O Times for CIP Connections A 3 Chapter 1 EtherNet IP Overview Introduction This document provides an application example to help estimate the performance of an EtherNet IP control system This chapter provides a brief overview of an EtherNet IP network and provides a list of reference materials that you can use to find detailed information about planning and configuring a network For this information See this page EtherNet IP Overview 1 1 Planning an EtherNet IP Network 1 2 Planning an EtherNet IP Network 1 2 Additional Reference Materials 1 3 EtherN et IP Overview EtherNet IP is a network suitable for use in industrial environment and time critical applications EtherNet IP uses standard Ethernet and TCP IP technologies and an open application layer protocol called the Control and Information Protocol CIP CIP is also the application layer used in DeviceNet and ControlNet networks The open Application Layer protocol mak
17. 1 ms The same concept can be used for produced tags and consumed tags by replacing the 2 x connections with 1 connections for produced tags or 2 RPI for consumed tags Predict System Performance 4 7 Estimate maximum input or output times for CIP connections System response is dependent on several factors The dominant factors are RPI and the number of implicit CIP connections To simplify the response time of a connection can be approximated with only the RPI The maximum input I O to controller or output controller to I O times for implicit CIP connections can be estimated as follows With this approximation the error will be less than 10 if the RPI in milliseconds is at least 10 times the number of connections through the EtherNet IP interface A Rack Optimized 1 RPI B Direct Connect Discrete 1 RPI Analog non isolated 2 RTS Analog isolated 1 RTS C Produced Consumed Tag 1 RPI The above response times are estimates For more accurate numbers include system delays See page 4 16 for more information Example Predict System This example system has the following components Performance e A controller that controls the I O and produces a tag that is consumed by two other processors at an RPI of 20 ms e Twenty five digital I O modules using rack optimized connections with specified RPIs of 20 ms e Fifteen analog I O modules using direct connections with specified RPIs of 50 ms e One Panel
18. Allen Bradley EtherNet IP Performance Application Solution Ua 7 Rockwell Automation na Important User Information Solid state eguipment has operational characteristics differing from those of electromechanical equipment Safety Guidelines for the Application Installation and Maintenance of Solid State Controls Publication SGI 1 1 available from your local Rockwell Automation sales office or online at http www ab com manuals gi describes some important differences between solid state equipment and hard wired electromechanical devices Because of this difference and also because of the wide variety of uses for solid state equipment all persons responsible for applying this equipment must satisfy themselves that each intended application of this equipment is acceptable In no event will Rockwell Automation Inc be responsible or liable for indirect or consequential damages resulting from the use or application of this equipment The examples and diagrams in this manual are included solely for illustrative purposes Because of the many variables and requirements associated with any particular installation Rockwell Automation Inc cannot assume responsibility or liability for actual use based on the examples and diagrams No patent liability is assumed by Rockwell Automation Inc with respect to use of information circuits equipment or software described in this manual Throughout this manual we use notes to
19. EtherNet IP becomes a highly deterministic network that works well for I O control If a device is forced to a specific duplex auto negotiation is disabled then the switch defaults to half duplex It is best to let the device auto negotiate Publication ENET AP001D EN P October 2004 2 2 Select an Ethernet Switch IGMP Snooping Port Mirroring Publication ENET AP001D EN P October 2004 Much of EtherNet IP implicit 1 0 messaging uses IP multicast to distribute I O control data which is consistent with the CIP produced consumer model Historically most switches have treated multicast packets the same as broadcast packets That is multicast packets are re transmitted to all ports IGMP snooping constrains the flooding of multicast traffic by dynamically configuring switch ports so that multicast traffic is forwarded only to ports associated with a particular IP multicast group Switches that support IGMP snooping learn which ports have devices that are part of a particular multicast group and only forward the multicast packets to the ports that are part of the multicast group Be careful as to what level of support of IGMP snooping a switch has Some layer 2 switches that support IGMP snooping require a router which could be a layer 3 switch to send out IGMP polls in order to learn what devices are part of the multicast group Some layer 2 switches can use IGMP snooping without a router sending polls If your con
20. Net IP module has a maximum number of packets second Bandwidth should be allocated as follows e Reserve 10 of each EtherNet IP module s bandwidth to allow for processing of explicit messages e The total for implicit messaging should not exceed 90 of capacity for each EtherNet IP module IMPORTANT If you do not reserve at least 10 of each EtherNet IP module s bandwidth you might not be able to go online with RSLogix 5000 software ot be able to access the EtherNet IP module s embedded web server To remedy this situation remove AC power on one or more racks to reduce the EtherNet IP traffic in the overloaded EtherNet IP modules Then go online with RSLogix 5000 software to reconfigure the RPIs to a less frequent slower rate Publication ENET AP001D EN P October 2004 Predict System Performance 4 5 Each CIP connection is bi directional and therefore reguires a minimum of 2 packets per RPI Using 2 packets RPI connection the number of packets second to or from each EtherNet IP module can be calculated as follows A Rack Optimized Packets Second 2 x connections RPI B Direct Connect Packets Second 2 x connections RPI C Produced Tag producer and all consumers are in different chassis and operating at a uniform RPI At Producer Packets Second 1 connections RPI for each produced tag At Consumer Packets Second 2 RPI for each consumed tag For each EtherNet IP module the total packets sec
21. View with a direct connection to an array of 40 tags at 100 ms RPI and an explicit connection to an array of 100 tags sent every 300 ms e One workstation running RSView32 requiring explicit messaging of an array of 1500 tags every 100 ms This workstation also connects to the company Intranet Publication ENET AP001D EN P October 2004 4 8 Predict System Performance Part Determine if the system has sufficient bandwidth to fulfill the requirements of the application Based on the system requirements the initial network diagram is shown below Main 1 Produced Controller 2 Controller 3 Controller Tag Consumer Consumer Workstation EtherNet IP EtherNet IP EtherNet IP with module 1 module 2 module 3 RSView To Company Intranet AA SWITCH EtherNet IP module 4 3 Analog 5 Digital EtherNet IP TeEtherneyiP EtherNet IP EtherNet IP module 5 module 6 module 7 module 8 3 Analog 3 Analog 3 Analog 3 Analog Panel View 5 Digital 5 Digital 5 Digital 5 Digital Explicit messaging The RSView messages and the explicit messages from the PanelView are explicit messaging Reserve 10 of the bandwidth of the EtherNet IP module for explicit messaging EtherNet IP Interface Total Bandwidth packet
22. an be problems which result in a high rate of CRC errors All 100 Mbps devices are required to support autonegotiation but most existing 10 Mbps devices do not Select a switch that supports both speeds so you can connect to existing devices such as 1756 ENET modules The switch fabric is a measure of the maximum traffic that a switch can handle without dropping a packet and without storing a packet in memory Wire speed switching fabric refers to a switch that can handle the maximum data rate of the network on each of its ports Switches are typically rated in Gbps For a 10 port switch connected to EtherNet IP products the maximum data rate needed is typically in the 100 200 of Mbps range Therefore a 10 port switch rated at least 1 Gbps should be adequate for an EtherNet IP implementation SNMP is a TCP IP protocol for obtaining statistical information about a device SNMP software lets a network manager view and modify a wide variety of network parameters and provides a common way to manage many diverse vendor products Publication ENET AP001D EN P October 2004 2 4 Select an Ethernet Switch Notes Publication ENET AP001D EN P October 2004 Chapter 3 Introduction Connection Overview How Connections and Multicast Frames Affect Data Transfer For information about See page Connection Overview 3 1 TCP Connections 3 3 CIP Connections 3 4 TCP and CIP Timeouts 3 8 Multicast Frames 3 9 A connection
23. chnical publications will help us serve you better in the future Thank you for taking the time to provide us feedback wy You can complete this form and mail it back to us visit us online at www ab com manuals or email us at RADocumentComments ra rockwell com Pub Title Type EtherNet IP Performance and Application Cat No EtherNet IP products Pub No ENET AP001D EN P Pub Date October 2004 Part No 957899 85 Please complete the sections below Where applicable rank the feature 1 needs improvement 2 satisfactory and 3 0utstanding Overall Usefulness 1 2 3 How can we make this publication more useful for you c 1 2 3 Can we add more information to help you ompleteness all necessary information procedure step illustration L feature ided is provided F example T guideline L other C explanation C definition Technical Accuracy 1 2 3 Can we be more accurate all provided information dlp is correct text te illustration Clarity 1 2 3 How can we make things clearer all provided information is easy to understand Other Comments You can add additional comments on the back of this form Your Name Location Phone Your Title Function Would you like us to contact you regarding your comments No there is no need to contact me Yes please call me Yes please email me at Yes please contact me via Return this form to Al
24. dapter Producer Controller Consumer Controller rack output data input data n a n a input data heartbeat input data n a n a output data output data output data echo n a n a produce tag n a n a tag data heartbeat Performance Calculations To predict the maximum input I O to controller or output controller to I O times for CIP connections continue with the following steps 7 Estimate the maximum time intervals for e rack optimized connections e direct connections produced tags 8 If necessary modify your system to get more throughput by performing one or more of the adjustments described under step 5 9 If you have made further modifications verify that the modified system will work The performance predictions involve three sets of simple calculations 1 Identifying and counting the number of connections 2 Calculating the packets second loading 3 Estimating the maximum input or output times Publication ENET AP001D EN P October 2004 4 4 Predict System Performance Identify and count connections Use your design to identify and count the total number of rack optimized connections direct connections and produced consumed tag connections for each EtherNet IP module in your system Performance prediction is done on a CIP connection basis Main ControlLogix Remote ControlLogix m Start Here Finish Here O 2 Calculate packets second Each Ether
25. end node connections In addition to the CIP connections the 1788 ENBT supports e Maximum of 32 controllers can consume data from an implicit connection 1734 AENT Each module has a maximum of 32 CIP connections of which e There are 0 bridged connections e Maximum of 5 controllers with any combination of rack optimized connections and listen only rack optimized connections e Maximum of 32 explicit end node connections e Maximum of 20 implicit end node connections this includes rack optimized and listen only rack optimized connections 1794 AENT Each module has a maximum of 32 CIP connections of which e There are 0 bridged connections e Maximum of 32 explicit end node connections e Maximum of 31 implicit end node connections In addition to the CIP connections the 1794 AENT supports e Maximum of 31 controllers can consume data from a direct connection Publication ENET AP001D EN P October 2004 How Connections and Multicast Frames Affect Data Transfer 3 7 CIP unconnected messaging limits The following limits of unconnected messages are the maximum number of outstanding unconnected messages These are unconnected messages that have been sent to the device and are being processed and have not yet generated a response or timeout Product CIP Unconnected Messaging Limits 1756 ENBT Each module has a maximum of 256 CIP unconnected messages of which a e Maximum of 128 unconnected messages f
26. ent module less than a minute However some switches will not forward the gratuitous ARP message onto the network in particular if the Spanning Tree Protocol is enabled on that port It is recommended that you disable the Spanning Tree Protocol on those ports to which EtherNet IP modules are directly connected but not on ports which are linked to other switches In the worst case if the gratuitous ARP is not seen an originating device could wait as long as 10 minutes for the ARP cache entry to age out and be deleted CIP timeouts Description The multiplier is selected by the controller firmware so that the timeout is greater than or equal to 100 ms The minimum multiplier is 4 Example 1 RPI 2ms the controller selected multiplier 64 The timeout is 128ms Example 2 RPI 10ms the controller selected multiplier 16 The timeout is 160ms explicit message 30 seconds Publication ENET AP001D EN P October 2004 For explicit messages connected or unconnected the timeout is 30 seconds This is user changeable in the Message MSG instruction structure Multicast Frames How Connections and Multicast Frames Affect Data Transfer 3 9 All input data from I O devices is sent multicast Therefore each frame is broadcast throughout the system to make sure it reaches all the possible devices in the multicast group to plant network switch or router layer 2 lt a layer 2 swi
27. es interoperability and interchangeability of industrial automation and control devices on EtherNet IP a reality for automation and control applications CIP EN50170 ControlNet International Control and Information Specification and Protocol IEC 61158 Standard Bi m ee IETF IP Multicast 7 UDP TCP IP Ai Ethernet MAC Ethernet Physical Publication ENET AP001D EN P October 2004 1 2 EtherNet IP Overview EtherNet IP supports both time critical implicit and non time critical explicit message transfer services of CIP Exchange of time critical messages is based on the producer consumer model where a transmitting device produces data on the network and many receiving devices can consume this data simultaneously EtherNet IP supports these functions e Time critical message exchange for I O control e Human Machine Interface HMI e Device configuration and programming e Device and network prognostics and diagnostics e Compatibility with SNMP and web pages embedded in devices Support of these functions along with interoperability and interchangeability positions EtherNet IP as an open network standard for Ethernet based industrial automation Planning an EtherNet IP When planning an EtherNet IP network follow these steps Network Step Issue to Decide Generate functional requirements for the network e EtherNet IP technology e Physical medium e Topology e Mode of operation half d
28. ess etc which is implied in the message but not contained in the message explicit connection Explicit connections are non time critical and are request reply in nature Executing a MSG instruction or executing a program upload are examples of explicit connections Explicit refers to basic information source address data type destination address etc that is included in every message producer and consumer Producer consumer refers to implicit connections With implicit connections messages are sent cyclically every RPI Example Assume a ControlLogix controller is controlling a single rack of Flex 1 0 using a rack connection Both the ENBT module that is local to the controller and the Flex AENT module are consumers and producers of data The AENT consumes outputs and produces inputs client and server Client server refers to explicit connections A client creates a connection and initiates messages A server provides a service or data Clients can send messages continuously or intermittently Example A ControlLogix controller can send a MSG instruction to another controller transports Each connection has transports A transport is a uni direction entity with its own numeric identifier A implicit connection has 2 transports A explicit connection has 1 transport Transports are important because they help you calculate the number of packets per second for each Ethernet interface Example 1 1 0 For an
29. hat these times are acceptable for the example application If you find that the times for your system are too slow you can make adjustments to operate at faster RPIs This may entail selecting I O modules that operate at faster data rates adding more EtherNet IP modules and or other changes as outlined in step 5 on page 4 2 No further modifications have been made so the system is complete Refine estimates To further increase the accuracy of these times include considerations for system delays For a Rack Optimized Connection to the RPI add these delays TMAX Rack Optimized input filter RPI transmission switch queue Type of delay input filter Predict System Performance 4 17 where Description Discrete input modules have filters The default for a 1756 discrete I O module is 1 ms For The default for a FLEX discrete 1 0 module is 0 25 ms input delay 1 ms There are no filters for outputs so there is no additional delay for outputs Outputs are always sent using an RPI timer transmission The transmission delay is the interval of time that it takes a packet to be transmitted at a specific bit rate e g 100Mbps For example in a 7 slot ControlLogix chassis the size of the entire packet is approximately 122 bytes including header all protocols all data and CRC At 100Mbps this packet takes approximately 10 microseconds 0 01 ms on the wire transmission delay 0 01 ms x number
30. ion ENET AP001D EN P October 2004 A 4 Worksheets Notes Publication ENET AP001D EN P October 2004 A additional references 1 3 application bandwidth 4 2 4 7 autonegotiation 2 3 B bandwidth 4 2 4 7 C calculate packets second 4 4 calculations 4 3 CIP connections calculate delays 4 16 calculate times 4 16 connected messages 3 5 messages 3 4 overview 3 1 predict times 4 3 4 7 timeouts 3 8 unconnected messages 3 7 client 3 2 connected messages 3 5 connections calculate CIP delays 4 16 calculate CIP times 4 16 count identify connections 4 4 identify 4 4 multicast addresses 3 10 overview 3 1 plan 3 1 predict CIP times 4 3 4 7 TCP 3 3 terminology 3 2 consumed tags 4 10 consumer 3 2 count connections 4 4 D delay times 4 16 Index E equations 4 3 estimate RPI 4 6 times for CIP connections 4 7 EtherNet IP module packets second worksheet A 1 EtherNet IP modules serving as adapters 4 9 EtherNet IP modules serving as scanners 4 11 example achieve more throughput 4 12 calculate times for CIP connections 4 16 conclusion 4 15 consumed tags 4 10 delay times for CIP connections 4 16 determine bandwidth 4 8 EtherNet IP modules serving as adapters 4 9 EtherNet IP modules serving as scanners 4 11 explicit messaging 4 8 system performance 4 7 explicit connection 3 2 explicit messaging 4 1 4 8 F frames 3 9 full duplex 2 1 IGMP snooping 2 2 implicit connection 3 2 implicit messaging 4 1 K
31. ions TCP connections are required for EtherNet IP communications TCP connections are used for unconnected CIP messages and for CIP explicit connections Examples of TCP connections are e HMI human machine interface to a controller that supports EtherNet IP communications e Logix MSG instruction to a controller or workstation e OPC or DDE accessing a controller TCP connection limits Product TCP Connection Limits 1756 ENBT 1756 ENET B 1756 EWEB 64 TCP connections 1769 L32E These modules also have web servers which use TCP connections for non CIP traffic 1769 L35E HTTP These TCP connections do not count toward the 64 connection maximum 1788 ENBT 1794 AENT 1734 AENT as many TCP connections as memory is available Publication ENET AP001D EN P October 2004 3 4 How Connections and Multicast Frames Affect Data Transfer CIP Connections CIP connection type bridged connection CIP connections are required for both implicit and explicit messaging Examples of functions supported by CIP connected messaging include e Logix controller message transfer to Logix controller e I O or produced tag e Program upload e RSLinx DDE OPC client e PanelView polling of Logix controller There are different types of CIP connections Description A bridged connection is a connection that passes through the EtherNet IP module The end point of the connection is a module other than the EtherNet IP module Example an explicit connecti
32. ions to I O racks at RPIs of 20 ms 15 direct connections at 50 ms RPIs for the analog modules and 1 produced tag with 2 connections to EtherNet IP modules 2 and 3 Fill in the worksheet for this module as follows for I O PanelView for I O Packets Second 14 for EtherNet IP Module ID 1 Rack Optimized Connections _5 20 ms Packets Second 2 x connections RPI 2x 5 20 ms 500 Direct Connections 1 100 ms Packets Second 2 x connections RPI 2 x 1 100 ms 20 Direct Connections _15 50 ms Packets Second 2 x connections RPI 2x 15 50 ms 600 Produced Tag Connections _2 20 ms connections RPI each produced tag 14 Consumed Tags 0 Total Packets Second Packets Second 2 RPI for each consumed tag in 2 20 ms N A 1270 Publication ENET AP001D EN P October 2004 4 12 Predict System Performance The total of 1270 packets second is within the limit for a 1756 ENBT module but it well exceeds the recommended limit for a 1756 ENET B module This system does not work for a chassis containing a 1756 ENET B module Recommendations to achieve more throughput with an existing 1756 ENET B module To achieve more throughput with an existing 1756 ENET B module do one of the following e Add a1756 ENBT or 1756 ENET B module e Replace the 1756 ENET B module with a 1756 ENBT module In th
33. is example module 1A is an ENET B module Add module 1B as a 1756 ENBT module Main Controller 2 Controller 3 Controller Consumer Consumer Wore ENET B ENBT EtherNet IP oe RSView IA module 2 module To Company Intranet lt SWITCH EtherNet IP EtherNet IP EtherNet IP EtherNet IP EtherNet IP module 4 module 5 module 6 module 7 module 8 3 Analog 3 Analog 3 Analog 3 Analog 3 Analog Panel View 5 Digital 5 Digital 5 Digital 5 Digital 5 Digital Publication ENET AP001D EN P October 2004 In this configuration divide the scanning function between the 1756 ENET B and 1756 ENBT modules For example connect EtherNet IP modules 2 5 and the Panel View to the 1756 ENET B module 1A and connect EtherNet IP modules 6 8 to the 1756 ENBT module 1B The RSLogix 5000 software I O configuration for the rack optimized and direct connections in this system is shown below This configuration is done in the Main Controller in rack number 1 Predict System Performance 4 13 These example configurations show generic EtherNet IP modules as the adapters under module 1A and module 1B You could select any EtherNet IP module that works for your application 1734 AENT 1756 ENBT 1794 AENT Panel View terminal etc For the control processor I O Config
34. len Bradley Marketing Communications 1 Allen Bradley Dr Mayfield Hts OH 44124 9705 Phone 440 646 3176 Fax 440 646 3525 Email RADocumentComments ra rockwell com Publication ICCG 5 21 January 2001 PN 955107 82 Other Comments PLEASE FASTEN HERE DO NOT STAPLE PLEASE FOLD HERE BUSINESS REPLY MAIL FIRST CLASS MAIL PERMIT NO 18235 CLEVELAND OH POSTAGE WILL BE PAID BY THE ADDRESSEE Allen Bradley BELIANCE ya ELECTRIC Snr DOGE Rockwell Automation 1 ALLEN BRADLEY DR MAYFIELD HEIGHTS OH 44124 9705 NO POSTAGE NECESSARY IF MAILED IN THE UNITED STATES PLEASE REMOVE Rockwell Automation Rockwell Automation provides technical information on the web to assist you Support in using our products At http support rockwellautomation com you can pp find technical manuals a knowledge base of FAQs technical and application notes sample code and links to software service packs and a MySupport feature that you can customize to make the best use of these tools Por an additional level of technical phone support for installation configuration and troubleshooting we offer TechConnect Support programs For more information contact your local distributor or Rockwell Automation representative or visit http support rockwellautomation com Installation Assistance If you experience a problem with a hardware module within the first 24 hours of installation please revie
35. make you aware of safety considerations WARNING Identifies information about practices or circumstances that can cause an explosion in a hazardous environment which may lead to personal injury or death property damage or economic loss IMPORTANT Identifies information that is critical for successful application and understanding of the product Identifies information about practices or circumstances that can ATTENTION P lead to personal injury or death property damage or economic loss Attentions help you e identify a hazard e avoid a hazard recognize the consequence UTU Labels may be located on or inside the drive to alert people that dangerous voltage may be present BURN HAZARD Labels may be located on or inside the drive to alert people that surfaces may be dangerous temperatures Summary of Changes This document help you plan your EtherNet IP network and describes considerations for improving overall network performance Revision bars in the margin identify updated information Changes for this version of the document include e information on selecting an Ethernet switch see chapter 2 addition of information regarding multicast frames see page 3 9 addition of information for the 1756 EWEB web server module see chapter 3 addition of information for the 1769 L32E and 1769 L35E CompactLogix controllers see chapter 3 addition of information for the 1734 AENT POINT
36. n ENET AP001C EN P January 2003 Copyright 2004 Rockwell Automation All rights reserved Printed in the U S A
37. odva org ENET IN001 Rockwell Automation manuals are available in the EtherNet IP Media Planning and Installation Guide Automation Bookstore ENET UMOO1 See http Awww theautomationbookstore com EtherNet IP Modules in Logix5000 Control Systems User Manual Publication ENET AP001D EN P October 2004 1 4 EtherNet IP Overview Notes Publication ENET AP001D EN P October 2004 Chapter 2 Select an Ethernet Switch l Introduction For information about See page Switch Functionality for EtherNet IP Systems 2 1 Full Duplex Capability on all Ports 2 1 IGMP Snooping 2 2 Port Mirroring 2 2 VLAN Virtual Local Area Network 2 3 Autonegotiation 2 3 Wire Speed Switching Fabric 2 3 SNMP Simple Network Management Protocol 2 3 Switch Functionality for When using EtherNet IP for time critical implicit messaging for 1 0 control there are several features available in switches that are required and or EtherNet IP Systems a Required or Recommended Switch Feature required e full duplex capability on all ports e IGMP snooping e port mirroring recommended e VLAN e autonegotiation and manually configurable speed duplex e wire speed switching fabric e SNMP Full Duplex Capability on Full duplex capability eliminates collisions Combined with the speed of the all Ports switches available today you can eliminate the delays related to collisions or traffic in the switch The end result is that
38. on from a controller through a 1756 ENBT to another controller end node connection An end node connection is a connection whose end point is the EtherNet IP module itself Example an explicit connection from RSLinx to the EtherNet IP module to set the module s IP address rack optimized A rack optimized connections is an implicit message connection to a rack or assembly object in the EtherNet IP module Data from selected 1 0 modules is collected and produced on one connection the rack optimized connection rather than on a separate direct connection for each module direct Publication ENET AP001D EN P October 2004 An implicit message connection from a controller to an specific 1 0 module as opposed to a rack optimized connection Product 1756 ENBT How Connections and Multicast Frames Affect Data Transfer 3 5 CIP connected messaging limits CIP Connected Messaging Limits Each module has a maximum of 128 CIP connections of which e Maxim connec e Maxim In addition to the e Maxim the mo e Maxim to the mo e Maxim um of 128 bridged connections any combination of implicit and explicit tions um um dul um um of 32 end node connections CIP connections the 1756 ENBT supports of 16 controllers that can have a rack optimized connection to e of 16 controllers that can have a rack optimized listen only connection dule of 64 controllers can consume data from
39. ond is the sum of the above This total should not exceed the recommended 90 packets second limit How the RPI you configure translates into the actual packet interval APT depnds on the controller initiating the communication Both RPI and and API are in milliseconds In general e ControlLogix API RPI e CompactLogix API 2 e FlexLogix API 2 e SoftLogix API RPI where 2 is a value that is a power of 2 such as 2 4 8 16 etc that is equal to or faster than the RPI you configured So in most cases you can get data faster than the RPI you configured which can increase the number of packets second to be more than you expected based on the RPI Publication ENET AP001D EN P October 2004 4 6 Predict System Performance Publication ENET AP001D EN P October 2004 Estimate the fastest RPI The fastest RPI for an EtherNet IP interface is RPI fastes 2 x connections pps MASINA lis not necessary to operate at the fastest RPI Example 1 The 1756 ENBT supports 5000 pps If there are only four connections that are all at the same RPI the fastest RPI is RPI fastest 2x 4 5000 1 6 ms Example 2 Assume there are three connections already running at an RPI of 2 ms on a 1756 ENBT module These connections are already using some of the communication packets pps 2x3 2 ms 3000 pps The fastest RPI possible for a fourth connection is RPI fastest for 4 connection 2 x 1 5000 3000
40. rom the EtherNet IP port to an object on the module or to the backplane e Maximum of 128 unconnected messages from the backplane to an object on the module or to the EtherNet IP port 1769 L32E Each module has a maximum of 64 CIP unconnected messages of which 1769 L33E e Maximum of 32 unconnected messages from the EtherNet IP port to the host e Maximum of 32 unconnected messages from the host to the EtherNet IP port 1788 ENBT Each module has a maximum of 64 CIP unconnected messages of which e Maximum of 32 unconnected messages from the EtherNet IP port to the host e Maximum of 32 unconnected messages from the host to the EtherNet IP port 1734 AENT Each module has a e Maximum of 20 simultaneous unconnected messages from the EtherNet IP port to the backplane e Maximum of 32 simultaneous unconnected messages from the EtherNet IP port to an object on the module 1794 AENT Each module has a maximum of 256 CIP unconnected messages from the EtherNet IP port The 1794 AENT can receive messages from the EtherNet IP port Because the FLEX 1 0 backplane uses a polled architecture the FLEX modules 1 0 modules do not initiate messages to the 1794 AENT module Publication ENET AP001D EN P October 2004 3 8 How Connections and Multicast Frames Affect Data Transfer TCP and CIP Timeouts Approximate Timeout keep alive 2 minutes TCP IP Stack timeout not user configurable Description Source and target stacks periodically talk to
41. s for each I O connection Example 2 A Logix controller that produces tags uses a unique multicast address for each produced tag The multicast address limit is independent of the connection limit for a device Not all connections requite a multicast address And in the case of produced and consumed tags one produced tag requires one multicast address but it also requires one connection for each consumer If there are multiple consumers the one multicast address would be using multiple connections Chapter 4 Predict System Performance Introduction This chapter describes how to predict the performance of your EtherNet IP based control system and how to enhance that performance For information about See page System Prediction Goals 4 1 Part Determine if the system has sufficient bandwidth to 4 2 fulfill the requirements of the application Part Il Predict the maximum input or output times for 4 3 CIP connections Performance Calculations 4 3 Example Predict System Performance 4 7 System Prediction Goals You allocate the bandwidth of your EtherNet IP communication module between two types of messaging Messaging Type Description explicit messaging Explicit messages are connections that do not use an RPI Explicit messaging includes MSG PanelView RSView RSLogix 5000 uploads and downloads etc implicit messaging Implicit messages are connections that use an RPI Implicit messaging is used for 1
42. s second 10 Reserve for Explicit Messaging packets second 1756 ENBT 5000 pps 500 pps 1756 ENET B 900 pps 90 pps 1769 L32E 4000 pps 400 pps 1769 L35E 1788 ENBT 5000 pps 500 pps 1734 AENT 5000 pps 500 pps 1794 AENT 9500 pps 950 pps Publication ENET AP001D EN P October 2004 Explicit messaging throughput is also dependent upon network availability and target availability Therefore reserving 10 of the total bandwidth does not guarantee throughput Predict System Performance 4 9 Nezt determine if each EtherNet IP module has enough bandwidth to handle the implicit messaging EtherNet IP modules serving as adapters Each EtherNet IP module serving as an adapter in an I O rack EtherNet IP modules 4 to 8 in the example on page 4 8 has one rack optimized connection for digital I O and three direct connections for analog I O The digital 1 0 has a required RPI of 20 ms and the analog I O has a required RPI of 50 ms For example use the packets second worksheet in Appendix A for each of the five EtherNet IP modules as follows EtherNet IP Module ID 4 8 Rack Optimized Connections 1 20 ms Packets Second 2 x connections RPI 2x 1 20 ms 100 Direct Connections 3 50 ms Packets Second 2 x connections RPI 2 x 3 50 ms 120 Produced Tag Connections _ 0 Packets Second 1 connections RPI for each produced tag N A Consumed Tags 0 Packets Second 2 RPI for each consumed tag
43. tch switch controller 1 0 consumer producer I O devices generally produce at very fast rates such as 10 ms so it is easy to flood the network with multicast traffic and force each end device to spend time deciding whether to discard numerous multicast frames If there are a lot of I O devices they can easily use up a significant part of a routers CPU time You must consider control network traffic propagating onto the plant information network as well as plant information network traffic propagating onto the control network Some best practices to follow are e Minimize device load due to unwanted IP multicast traffic e Minimize switch load due to unwanted IP multicast traffic e Minimize network load due to unwanted incoming IP multicast or broadcast traffic e Block IP multicast traffic generated within the Ethernet IP subnet from propagating onto the plant network e Implement standard network troubleshooting tools Publication ENET AP001D EN P October 2004 3 10 How Connections and Multicast Frames Affect Data Transfer Publication ENET AP001D EN P October 2004 Multicast address limit Implicit connections that produce data over an EtherNet IP network use multicast addresses EtherNet IP interfaces support a maximum of 32 unique multicast addresses The actual address such as 239 192 22 121 is determined by the EtherNet IP interface Example 1 An ethernet adapter that produces data uses a unique multicast addres
44. trol system is a stand alone network or is required to continue performing if the router is out of service make sure the switch you are using supports IGMP snooping without a router present Port mirroring is for troubleshooting Port mirroring refers to the ability to direct the frames being transmitted on one port to another port This lets a traffic analyzer to connected to a switch have the ability to monitor the traffic on a given port Without port mirroring an analyzer cannot see frames on other ports With hubs this is not an issue because all frames are transmitted out all ports Select a switch that supports port mirroring so that a traffic analyzer can function correctly on the network Traffic analyzers are critical to supporting and maintaining Ethernet networks VLAN Virtual Local Area Network Autonegotiation Wire Speed Switching Fabric SNMP Simple Network Management Protocol controller 1 Select an Ethernet Switch 2 3 With VLANs you can configure a switch to share two isolated networks without the traffic from one network burdening the other IP multicast traffic from VLAN 1 will not reach VLAN 2 A VLAN blocks broadcast traffic and adds a measure of security between networks controller 2 switch Autonegotiation lets devices select the most optimal way to communicate without the you having to configure the devices However if you connect a manually configured to an autonegotiation device there c
45. uplex or full duplex e Web access Determine network infrastructure e Network configuration hierarchy separate business and control traffic use Ethernet switches instead of hubs e Layer 2 switch selection required features include 10 100Mbps full duplex IGMP snooping and port mirroring Layer 3 switch selection optional Media selection UTP STP fiber Any other infrastructure components Be aware of security issues Assign node IP addresses See the user manual for your EtherNet IP interface to determine the most appropriate method for assigning an IP address Determine data requirements implicit and explicit messages e Verify device capacity against load e TCP connections e CIP connections Estimate system performance e Determine if the system has sufficient bandwidth packets second e Predict the maximum input and output times e Calculate worst case 1 0 response e Estimate HMI traffic Publication ENET AP001D EN P October 2004 EtherNet IP Overview 1 3 Additional Reference The following documents provide detailed information about planning and M at eri al s configuring an EtherNet IP network These documents Are available as A11259018 Switch Considerations for Use with EtherNet IP KnowledgeBase articles See http support rockwellautomation com Select the Knowledgebase icon from the Customer Support page EtherNet IP standards documents ODVA web site See http www
46. uration f 1 1756 ENET B Local JA f ETHERNET MODULE Adapter_4 f ETHERNET MODULE Adapter_5 9 2 1756 ENBT A Local_1B f ETHERNET MODULE Adapter_6 f ETHERNET MODULE Adapter 7 f ETHERNET MODULE Adapter 8 The RSLogix 5000 software configurations for produced tags in this system is shown below These configurations are done in the consumers i e the processors in racks 2 and 3 For the consumer in rack 2 I O Configuration 9 1 1756 ENET B Consumer 2 E 0 1756 ENET B Scanner_14 i 1 1756 L55 Producer Controller For the consumer in rack 3 I O Configuration 9 1 1756 ENBT A Consumer_3 0 1756 ENBT A Scanner_1A 9 1 1756 L55 Produced_Controller In this new configuration 1756 ENET B module 1A has a produced tag with connections to the Consumer_2 and Consumer_3 modules at an RPI of 20 ms two rack optimized connections to the Adapter_4 and Adapter_5 modules at RPIs of 20 ms one direct connection to the PanelView at an RPI of 100 ms and six direct connections to the analog modules in racks 4 and 5 at RPIs of 50 ms Publication ENET AP001D EN P October 2004 4 14 Predict System Performance For 1756 ENET B module 1A calculate the total packets second as follows EtherNet IP Module ID _1A Rack Optimized Connections 2 20 ms for I O Packets Second 2 x connections RPI 2x 2 20 ms 200 Direct Connections
47. w the information that s contained in this manual You can also contact a special Customer Support number for initial help in getting your module up and running United States 1 440 646 3223 Monday Friday 8am 5pm EST Outside United Please contact your local Rockwell Automation representative for any States technical support issues New Product Satisfaction Return Rockwell tests all of our products to ensure that they are fully operational when shipped from the manufacturing facility However if your product is not functioning and needs to be returned United States Contact your distributor You must provide a Customer Support case number see phone number above to obtain one to your distributor in order to complete the return process Outside United Please contact your local Rockwell Automation representative for States return procedure www rockwellautomation com Power Control and Information Solutions Headquarters Americas Rockwell Automation 1201 South Second Street Milwaukee WI 53204 2496 USA Tel 1 414 382 2000 Fax 1 414 382 4444 Europe Middle East Africa Rockwell Automation Vorstlaan Boulevard du Souverain 36 1170 Brussels Belgium Tel 32 2 663 0600 Fax 32 2 663 0640 Asia Pacific Rockwell Automation Level 14 Core F Cyberport 3 100 Cyberport Road Hong Kong Tel 852 2887 4788 Fax 852 2508 1846 Publication ENET AP001D EN P October 2004 PN 957899 85 Supersedes Publicatio
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