jack douglass, spirent chair tia tr30.3 august 2004 tr30.3 tr30.3/04-08-018
DESCRIPTION
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 August 2004 TR30.3 TR30.3/04-08-018 [email protected]. TR30.3 Network Model Standards. - PowerPoint PPT PresentationTRANSCRIPT
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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
August 2004
TR30.3 TR30.3/04-08-018
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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 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
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Purpose of Presentation
• Establish a formal liaison between TR30.3 and appropriate committees to help develop TIA-921 (PN-3-0062), 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
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Network Model for Evaluating Multimedia Transmission Performance – TIA-921 (PN-3-0062)
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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
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IP Network Model
Core IP NetworkLAN A
Local AccessB
1000BaseX* 100BaseT Switch100BaseT Hub10BaseT* WLAN (~4 Mbit/s)----------------------Occupancy levelPacket loss
64 kbit/s*128 kbit/s256 kbit/s*384 kbit/s512 kbit/s*768 kbit/s
*T1 (1.536 kbit/s)E1 (1.920 kbit/s)E3 (34 Mbit/s)*T3 (44 Mbit/s)
ADSL (~256 kbit/s)*Cable (~256 kbit/s)Fiber (1-10 Gbit/s)
--------------------Occupancy levelQoS edge router
LAN B
Route flappingOne-way delay
JitterPacket loss
DestinationDevice B
Local AccessA
64 kbit/s*128 kbit/s256 kbit/s*384 kbit/s512 kbit/s*768 kbit/s
*T1 (1.536 kbit/s)E1 (1.920 kbit/s)E3 (34 Mbit/s)*T3 (44 Mbit/s)
ADSL (~2 Mbit/s)*Cable (~3 Mbit/s)Fiber (1-10 Gbit/s)
--------------------Occupancy levelQoS edge router
SourceDevice A
* Case used in impairment tables
1000BaseX* 100BaseT Switch100BaseT Hub10BaseT* WLAN (~4 Mbit/s)----------------------Occupancy levelPacket loss
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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 DUTsIP PhonesPOTS over IPMedia Gateways MGCUser AgentsCall Agents Media ServersVideo Gatekeepers Application Servers Edge Routers GatewaysModemsFax
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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 Type Units Range
Jitter ms +/- 75
One Way Latency ms 50 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
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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)
Del
ay (
ms)
Del
ay (
ms)
Del
ay (
ms)
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TIA-921 Test Profiles Based on QoS Classes
Test Profiles QoS Class(Y.1541)
Applications (Examples) Node Mechanisms Network Techniques
A(VoIP, MoIP, FoIP, ToIP)
0 Real-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)
1 Real-Time, Jitter sensitive, interactive (VoIP, VTC).
Separate Queue with preferential servicing, Traffic grooming
Less constrained Routing and Distances
C(FoIP only)
2 Transaction Data, Highly Interactive (Signaling)
Separate Queue, Drop priority
Constrained Routing and Distance
3 Transaction Data, Interactive Less constrained Routing and Distances
4 Low Loss Only (Short Transactions, Bulk Data, Video Streaming)
Long Queue, Drop priority Any route/path
5 Traditional Applications of Default IP Networks
Separate Queue (lowest priority)
Any route/path
• Statistically based models can be created for different QoS Classes
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TIA-921 Test Profiles Based on QoS (Y.1541) Classes
Impairment Type Units Range
Jitter ms +/- 50
One Way Latency ms 50 to 100
Sequential Packet Loss #sequential packets
Random loss only
Rate of Sequential Loss sec-1
Random Packet Loss % 0 to 10-3*
Out of Sequence Packets % 0 to 10-1**
Impairment Type Units Range
Jitter ms +/- 300
One Way Latency ms 200 to 500
Sequential Packet Loss #sequential packets
0 to 500
Rate of Sequential Loss sec-1 < 10-1*
Random Packet Loss % 0 to 10
Out of Sequence Packets % 0 to 10
Impairment Type Units Range
Jitter ms +/- 75
One Way Latency ms 50 to 150
Sequential Packet Loss #sequential packets
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**
Service Test profile C500 Impairment Combinations
Unmanaged Network
Service Test profile B500 Impairment Combinations
Managed Network
Service Test profile A500 Impairment Combinations
Well Managed Network
Different test profiles for different Service Level Agreements (SLAs)
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TIA-921Example 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)
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TIA-921 – Example of Network Model Coverage (NMC) Curve
Parameter X Vs Network Model Coverage Percentage
0
0 10 20 30 40 50 60 70 80 90 100
Percentage of Network Coverage
Device ADevice BDevice C
Qo
S,
PE
SQ
, P
SQ
M,
MO
S,
Th
rou
gh
pu
t, C
on
ne
ct R
ate
, e
tc.
Test Results from 500 Impairment Combinations
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Network Statistics/Characteristics Required to Validate IP Network Model
Home
Egress LOO %
128 20
256 80
Ingress
128 20
768 35
3000 45
LAN
4 60
10 40
Business
Access LOO %
1536 75
44000 25
LAN
4 35
100 50
1000 15
Likelihood of Occurrence of Business Data RatesLikelihood 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
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TIA-921 Target Audience for Network Model
• Operating Companies
• Service Providers
• Manufacturers
• Design Engineers
• Test houses
• Magazines and product reviewers