Analyze Assure Accelerate Network Model for Evaluating Multimedia Transmission Performance Over Internet Protocol PN Will become TIA/EIA-921 Jack Douglass, Spirent Chair TIA TR30.3 August 2004 TR30.3 TR30.3/

Analyze Assure Accelerate TR30.3 Network Model 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 : Test Procedures for Evaluation of 2-Wire 4 Kilohertz Voice Band Duplex Modems, which became ITU-T Recommendation V.56ter-1996 ANSI/TIA/EIA : Telephone Network Transmission Model for Evaluating Analog Modem Performance ANSI/TIA/EIA : 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

Analyze Assure Accelerate Purpose of Presentation Establish a formal liaison between TR30.3 and appropriate committees to help develop TIA-921 (PN ), Network Model for Evaluating Multimedia Transmission Performance Over Internet Protocol Other Liaisons Activities – TR41.4 – ITU-T SG12 -- Approved as Question M/12 – ITU-T SG11 – ITU-T SG13 – ITU-T SG15 Q7 – ITU-T SG16 Q11, Q14 (QF) – IETF – Etc. Invite committee members to TR30.3 meetings to work on IP Network Model – IP Network Statistics – Network Architecture – Test Scenarios

Analyze Assure Accelerate Network Model for Evaluating Multimedia Transmission Performance – TIA-921 (PN )

Analyze Assure Accelerate Parameters and Impairments that Affect Voice Quality Network Architecture Types of Access Links QoS controlled Edge Routing Voice coding algorithm A/D and D/A Conversion MTU Size Signaling protocol mismatches Network faults Link Failure Time Drift Route Flapping Echo Out of order packets Noise – Circuit and External Packet Loss (Frame Loss) One Way Delay (Latency) Variable Delays (Jitter) Background Traffic (Congestion, Bandwidth, Utilization, Network Load, Load Sharing ) ITU G.113 defines the transmission impairments and their impact on voice quality

Analyze Assure Accelerate IP Network Model

Analyze Assure Accelerate TIA-921 IP Network Impairment Emulator Jitter, Latency, Burst Loss, Gap Loss Packet Loss, Out-of-Order Packets Route Flapping, Link Failure Scenario Based Time Varying IP Network Impairments IP Network Impairment Emulator Types of DUTs IP Phones POTS over IP Media Gateways MGC User Agents Call Agents Media Servers Video Gatekeepers Application Servers Edge Routers Gateways Modems Fax

Analyze Assure Accelerate Testing with Fixed Levels of IP Impairments Impairments Placed in series between Tester and network equipment under test Test Examples: – Evaluate jitter buffer and packet loss concealment algorithms – Ability of equipment to handle impairments Impairment TypeUnitsRange Jitterms+/- 75 One Way Latencyms50 to 150 Sequential Packet Loss #sequential packets losses 0 to 3 Rate of Sequential Loss sec -1 < 10 -3* Random Packet Loss%0 to 2 Out of Sequence Packets %0 to 10 -1** Real Network Impairments Vary Over Time

Analyze Assure Accelerate TIA-921 – Statistically Based IP Network 500 Impairment Conditions (ICs) per SLA 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 500 test combinations so that an automated run of the test suite completes in less than a day. IC1 Prob (LOO X%) IC2 Prob (LOO X%) IC500 Prob (LOO X%) Time (s) Delay (ms)

Analyze Assure Accelerate TIA-921 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

Analyze Assure Accelerate TIA-921 Test Profiles Based on QoS (Y.1541) Classes Impairment TypeUnitsRange Jitterms+/- 50 One Way Latencyms50 to 100 Sequential Packet Loss#sequential packets Random loss only Rate of Sequential Losssec -1 Random Packet Loss%0 to 10 -3* Out of Sequence Packets%0 to 10 -1** Impairment TypeUnitsRange Jitterms+/- 300 One Way Latencyms200 to 500 Sequential Packet Loss#sequential packets 0 to 500 Rate of Sequential Losssec -1 < 10 -1* Random Packet Loss%0 to 10 Out of Sequence Packets%0 to 10 Impairment TypeUnitsRange Jitterms+/- 75 One Way Latencyms50 to 150 Sequential Packet Loss#sequential packets 0 to 3 Rate of Sequential Losssec -1 < 10 -3* Random Packet Loss%0 to 2 Out of Sequence Packets%0 to 10 -1** Service Test profile C 500 Impairment Combinations Unmanaged Network Service Test profile B 500 Impairment Combinations Managed Network Service Test profile A 500 Impairment Combinations Well Managed Network Different test profiles for different Service Level Agreements (SLAs)

Analyze Assure Accelerate TIA-921 Example Impairment Combination Table Approximately 1500 test Scenarios Run each Impairment Combination against rates Test Scenario Conditions (Impairment Combination – IC) IP Impairments Caused by Test Conditions (Impairment Combination – IC)

Analyze Assure Accelerate TIA-921 – Example of Network Model Coverage (NMC) Curve Test Results from 500 Impairment Combinations

Analyze Assure Accelerate Network Statistics/Characteristics Required to Validate IP Network Model Home EgressLOO % Ingress LAN Business AccessLOO % LAN Likelihood of Occurrence of Business Data Rates Likelihood of Occurrence of Home Data Rates Other Statistics/Characteristics Typical Impairment levels for SLAs Usage of QOS Edge Routing Route Flapping One Way Delay Packet loss Occupancy Level (Background Traffic) Validation of IP Impairment Characteristics (Algorithms) Who are the contacts in the service providers, operating companies, network equipment manufacturers that can provide this information? Similar network statistics were provided for the other TR30.3 network models anonymously by service providers, operating companies and network equipment manufacturers

Analyze Assure Accelerate TIA-921 Target Audience for Network Model Operating Companies Service Providers Manufacturers Design Engineers Test houses Magazines and product reviewers