1. Analyze Assure Accelerate Network Model for Evaluating Multimedia Transmission Performance Over Internet Protocol PN-3-0062 Will become TIA/EIA-921 Jack Douglass, Spirent Chair TIA TR30.3 March 2004 TR30.3 30403002 jack.douglass@spirentcom.com

2. Purpose of Presentation Establish a formal liaison between TR30.3 and TR41 to help develop Network Model for Evaluating Multimedia Transmission Performance Over Internet Protocol (PN-3-0062) Other Liaisons Activities – ITU-T SG11 – ITU-T SG13 – ITU-T SG12 – ITU-T SG15 Q7 – ITU-T SG16 Q11, Q14 (QF) – IETF – Etc. Invite TR41 members to TR30.3 meetings to work on IP Network Model – IP Network Statistics – Network Architecture – Test Scenarios

3. TR30.3 Modem Test Standards TIA/EIA 496A-1989: Interface Between Data Circuit Terminating Equipment (DCE) and the Public Switched Telephone Network – Included Network Model for Evaluating Modem Performance TIA/EIA TSB 37A-1994: Telephone Network Transmission Model for Evaluating Analog Modem Performance, which became ITU-T Recommendation V.56bis-1995 EIA/TIA TSB 38-1994: Test Procedures for Evaluation of 2-Wire 4 Kilohertz Voice Band Duplex Modems, which became ITU-T Recommendation V.56ter-1996 ANSI/TIA/EIA 3700-1999: Telephone Network Transmission Model for Evaluating Analog Modem Performance ANSI/TIA/EIA 793 -2000: North American Telephone Network Transmission Model for Evaluating Analog Client and Digitally Connected Server Modems ANSI/TIA 876 – 2002: North American Network Access Transmission Model for Evaluating xDSL Modem Performance

4. Network Model Coverage (NMC) Methodology Waterfall Curves – Traditional method of measuring modem performance – Error rate measured against single impairments such as Gaussian noise – Severe stress conditions Network Model Coverage (NMC) – Introduced by TR30.3 in TIA/EIA-1992 TSB37 – Network Model is a portrait of the real network – Statistically based Network Model -- Likelihood of Occurrence (LOO) of a given connection – Modem performance evaluated using a Impairment Combinations and Local Loop Combinations – Curve showing Percentage of Network Model Vs Throughput Estimates percentage of network of the real network over which the modem can be expected to operate – Compare performance of different models or manufactures of modems – Network Model is independent of modem technology

5. Network Model for Evaluating Multimedia Transmission Performance -- PN-3-0062

6. TIA-793 Network Model Converged Network Reference Model Diagram TIA-793 Network Model TE AD LL Telco Switch Gateway TE A D Telco Switch Gateway IP Network R,G,S* Gateway L L

7. Test Scenario: PSTN to PSTN connections through a managed IP network

8. Test Scenario: PSTN – IP connections

9. Test Scenario: IP – IP connections

10. Examples of Communication Equipment that can be tested over the Converged Network Model IP Network Devices such as User Agents, Call Agents, Media Servers, Media Gateway Controllers, Gatekeepers, Application Servers, Edge Routers, Gateways, IP Phones, IAF (Internet Aware Fax) Plain Old Telephone Service (POTS) and IP telephones Voice-over-IP (VoIP) gateways T.38 facsimile devices and gateways V.150.1 and voiceband data (VBD) modem-over-IP gateways TIA-1001 (and V.toip) textphone-over-IP gateways PSTN Video H320 and H324

11. Test Voice, Fax or Data over IP using Converged Network Model Voice, Video, Data, Fax, etc. Analog PSTN Simulator 1 IP Simulator Gateway Analog PSTN Simulator 2 Voice, Video, Data, Fax, etc.

12. Test IP Network Devices using IP Network Model IP Simulator IP Network Devices

13. Example of Test Profile with Fixed Values of Network Impairments Impairment TypeUnitsRange Jitterms+/- 75 One Way Latencyms50 to 150 Sequential Packet Loss#sequential packets losses0 to 3 Rate of Sequential Losssec -1 < 10 -3* Random Packet Loss%0 to 2 Out of Sequence Packets%0 to 10 -1** Network Impairments Conditions could be based on set of impairment combination that have fixed values – Stress IP Network Device Impairments on a real IP Network are not fixed

14. Parameters that Need to be Considered when Simulating an IP Network Network Architecture Types of Access Links QoS controlled Edge Routing Route Flapping Link Failure Load Sharing Time Drift MTU Size Packet Loss Background Traffic (Congestion, Bandwidth, Utilization, Network Load) One Way Delay

15. Example of Test Profile with Time Variable Network Impairments Time Packet Delay

16. Time Varying Statistically Based IP Network Impairment Conditions (ICs) Each Impairment Condition is assigned a Likely-hood of Occurrence (LOO) based on real IP Network Statistics, Network Architecture, Classes of Service The goal is to have approximately 100 test combinations so that an automated run of the test suite completes in less than a day. IC1 LOO X% IC2 LOO X% IC100 LOO X% Time

17. Test Profiles Based on QoS Classes Test ProfilesQoS Class (Y.1541) Applications (Examples)Node MechanismsNetwork Techniques A (VoIP, MoIP, FoIP, ToIP) 0Real-Time, loss sensitive, Jitter sensitive, high interaction (VoIP, VTC) Strict QoS. Guaranteed no over subscription on links. Constrained Routing and Distance B (VoIP, MoIP, FoIP, ToIP) 1Real-Time, Jitter sensitive, interactive (VoIP, VTC). Separate Queue with preferential servicing, Traffic grooming Less constrained Routing and Distances C (FoIP only) 2Transaction Data, Highly Interactive (Signaling) Separate Queue, Drop priority Constrained Routing and Distance 3Transaction Data, InteractiveLess constrained Routing and Distances 4Low Loss Only (Short Transactions, Bulk Data, Video Streaming) Long Queue, Drop priorityAny route/path 5Traditional Applications of Default IP Networks Separate Queue (lowest priority)Any route/path Statistically based models can be created for different QoS Classes

18. Example of Network Model Coverage (NMC) Curve

19. Value of Converged Network Model Predicts product performance under statistically base network conditions Finds design weaknesses Find compatibility issues between network equipment Facilitates isolating and resolving field problems Assists in evaluating different technologies

20. Target Audience for Converged Network Model Operating Companies Service Providers Manufacturers Design Engineers Test houses Magazines and product reviewers

21. Discussion Comments, Suggestions and Recommendations Input for Network Model – IP Network Statistics – Network Architecture – Test Scenarios Invited to participate in TR30.3