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 June 2004 TR30.3 TR30.3/

Purpose of Presentation Establish a formal liaison between TR30.3 and appropriate committees to help develop Network Model for Evaluating Multimedia Transmission Performance Over Internet Protocol (PN ) Other Liaisons Activities – ITU-T SG11 – ITU-T SG13 – ITU-T SG12 -- Approved as Question M/12 – 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

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 : 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

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

Signaling Path Converged IP Telephony Network is Very Complex and has Many Impairments

Network Topologies that need be considered when testing Audio Quality over a Converged Network

Network Model for Evaluating Multimedia Transmission Performance -- PN

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 PN (TIA/EIA-921) Network Model will focus on Transmission Performance Over Internet Protocol

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

Sources of IP Network Impairments

IP Network Model

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

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

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

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

Service Test profile A 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** * One Packet loss out 100,000 packets ** 1 Out of Sequence Packet per 1000

Service Test profile B Impairment TypeUnitsRange Jitterms+/- 75 One Way Latencyms50 to 150 Sequential Packet Loss#seque ntial 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** * Sequential Packet Loss occurs 1 every 1000 seconds ** 1 Out of Sequence Packet per 1000

Service Test profile C Impairment TypeUnitsRange Jitterms+/- 300 One Way Latencyms200 to 500 Sequential Packet Loss#sequenti al packets 0 to 500 Rate of Sequential Losssec -1 < 10 -1* Random Packet Loss%0 to 10 Out of Sequence Packets%0 to 10 * Sequential Packet Loss occurs 1 every 10 seconds

Core Network Impairment Severity Levels Impairment Route flapping Delay (ms) Jitter (ms) Packet loss % LOO (%)rate (s) ∆ delay (ms)Meanσ Severity A (hardest) Severity B Severity C Severity D (easiest)50 ∞

LAN Impairment Severity Levels LOO (%)Occupancy % timeOccupancy % capacityDuplex Mismatch Severity A (hardest)52060yes Severity B15 40yes Severity C301020no Severity D (easiest)50510no

Access Link Severity Levels LOO (%)Occupancy % timeOccupancy % capacityQoS edge router Severity A (hardest)560100off Severity B152540off Severity C301020on Severity D (easiest)50510on

Rationale for Access and LAN Rate Combinations Access link type(s) Access rate (kbit/s) LAN rate (Mbit/s) Home, Busines s Busines s ISDN, ADSL lite128MH00 Frac. T-1, ADSL lite, cable upstream256HM00 Fractional T-1384LLL0 Fractional T-1, ADSL768LLM0 T-1, ADSL1536MHH0 Cable modem downstream3000HH00 T HH Likelihood of occurrence: H = high, M = medium, L = low, 0 = very low

Impairment Severity Combinations (Service Test Profile A) LOO (%) LAN A (Origin ) Access A (Origin) Core Network Access B (Dest.) LAN B (Dest.) Severity A (hardest)5CCACC Severity B15CCBCC Severity C30DDCDD Severity D (easiest)50DDDDD

Impairment Severity Combinations (Service Test Profile B) LOO (%) LAN A (Origin ) Access A (Origin) Core Network Access B (Dest.) LAN B (Dest.) Severity A (hardest)5CCACC Severity B15CCBCC Severity C30DDCDD Severity D (easiest)50DDDDD

Impairment Severity Combinations (Service Test Profile C) LOO (%) LAN A (Origin ) Access A (Origin) Core Network Access B (Dest.) LAN B (Dest.) Severity A (hardest)5CCACC Severity B15CCBCC Severity C30DDCDD Severity D (easiest)50DDDDD

Data Rates for Home -> Home Direction Home -> Home Rate Combinations Access Rates (kbit/s) LAN Rates: Origin, Destination (Mbit/s) Lab elOrigin (A)Dest (B)4, 44, 1010, 410, 10 HH1128 HH100HH101HH110HH111 HH HH200HH201HH210HH211 HH HH300HH301HH310HH311 HH HH400HH401HH410HH411 HH HH500HH501HH510HH511 HH HH600HH601HH610HH611

Data Rates for Home -> Business Direction Home -> Business Rate Combinations Access Rates (kbit/s)LAN Rates: Origin, Destination (Mbit/s) Labe lOrigin (A)Dest (B)4, 44, 1004, , 410, 10010, 1000 HB HB100HB102HB103HB110HB112HB113 HB HB200HB202HB203HB210HB212HB213 HB HB300HB302HB303HB211HB312HB313 HB HB400HB402HB403HB212HB412HB413

Data Rates for Business -> Home Direction Business -> Home Rate Combinations Access Rates (kbit/s)LAN Rates: Origin, Destination (Mbit/s) Labe lOrigin (A)Dest (B)4, 44, 10100, 4100, , 41000, 10 BH BH100BH101BH120BH121BH130BH131 BH BH200BH201BH220BH221BH230BH231 BH BH300BH301BH320BH321BH330BH331 BH BH400BH401BH420BH421BH430BH431 BH BH500BH501BH520BH521BH530BH531 BH BH600BH601BH620BH621BH630BH631

Data Rates for Business - Business Business -> Business Rate Combinations Access Rates (kbit/s)LAN Rates: Origin, Destination (Mbit/s) Label Origin (A) Dest. (B)4, 44, 1004, , 4 100, , , , , 1000 BB11536 BB100BB102BB103BB120BB122BB123BB130BB132BB133 BB BB200BB202BB203BB220BB222BB223BB230BB232BB233 BB BB300BB302BB303BB320BB322BB323BB330BB332BB333 BB BB400BB402BB403BB420BB422BB423BB430BB432BB433

Example Impairment Combination Table Approximately 500 test per Service Class Profile

PN Simulator/Emulator

Example of Network Model Coverage (NMC) Curve

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 and voiceband data (VBD) modem-over-IP gateways TIA-1001 (and V.toip) textphone-over-IP gateways PSTN Video H320 and H324

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

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

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