Performance Evaluation of EF-Admit draft-gunn-tsvwg-ef-admit-evaluation-00 with updates

1. Performance Evaluation of EF-Admitdraft-gunn-tsvwg-ef-admit-evaluation-00with updates J. Gunn Computer Sciences Corporation R. Lichtenfels National Communications System D. Garbin D. Masi Noblis P. McGregor Nyquetek

2. Outline • Background / Motivation • EF-ADMIT • Scenarios/Assumptions • (updates since -00) • Results • (updates since -00) • Conclusions • Next Steps

3. Background / Motivation • EF-ADMIT proposed as a new DSCP to distinguish real time traffic subject to strict CAC from real time traffic subject to weak or no CAC • Interested in protecting ETS calls (as described in IEPREP) under severe congestion • Sustained high traffic • Extensive network failure • ETS calls can be subject to CAC (and thus can use EF-ADMIT) even when economic concerns mean that many “normal” calls are subject to weaker (or no) CAC. • How well can EF-ADMIT protect the ETS “strict CAC” calls when network is overloaded?

4. 2 EF - 2 Queue Model Policer 1 EF-ADMIT: Strict CAC Voice Priority Queue EF: Voice Policer 2 Line Transmission 256 Kb, 1.5 Mb, 45 Mb Baseline AF1: Video CBWFQ AF2: Data BE: Data EF = Expedited Forwarding (e.g., VoIP) AF1 = Assured Forwarding (Video) AF2 = Assured Forwarding (signaling) BE = Best Effort (Other Data) CBWFQ = Class Based Weighted Fair Queuing

5. 2 EF - 1 Queue Model Policer 1 EF-ADMIT: Strict CAC Voice Priority Queue EF: Voice Policer 2 Line Transmission 256 Kb, 1.5 Mb, 45 Mb Baseline AF1: Video CBWFQ AF2: Data BE: Data EF = Expedited Forwarding (e.g., VoIP) AF1 = Assured Forwarding (Video) AF2 = Assured Forwarding (signaling) BE = Best Effort (Other Data) CBWFQ = Class Based Weighted Fair Queuing

6. Scenarios/Assumptions (-01 version) • Access line speeds- 256 Kb, 1.5 Mb, 45 Mb • EF-ADMIT traffic is small compared to EF traffic (10% of base EF) • Baseline traffic mix includes EF/EF-ADMIT (Voice), AF1 (Video), AF2 (Data) and BE (Data) • Network Control traffic modeled as AF2- and is protected by EF policing • Baseline (overall) approx 80% utilization for 256 Kb, 1.5 Mb • Baseline (overall) approx 55% utilization for 45Mbps • 10X Overload applies to all except the EF-ADMIT and AF2 traffic • Policing • Regular” EF policed to approx 50% of line speed, • No policing on AF and BE • Primary Scenarios (for each speed) • 1EF, 1Q (current operation) • 2EF, 1Q • 2EF, 2Q • Secondary Scenarios- only for higher speeds • Mix Voice and Video in the EF-ADMIT stream

7. 256 Kbps Results • Delay and jitter for EF not relevant because only 10% of the packets for each call get through • For EF-ADMIT, delay is better for 2Q (14 ms vs. 23 ms), jitter is about the same (50 ms) • Drop rate almost identical for 1Q and 2Q 10 calls 1 call 10 calls, each getting 10 % 1 call, getting 100 %

8. 1.5 Mbps Results • Delay and jitter for EF not relevant because only 15% of the packets for each call get through • For EF-ADMIT, delay and jitter are both below 10 ms, for both 1Q and 2Q • Introducing EF-ADMIT video worsens delay and jitter for both EF and EF ADMIT- slightly worse for EF-ADMIT with1Q (5ms delay, 16 ms jitter) • Drop rate almost identical for 1Q and 2Q EF - 50 calls EF- ADMIT -1 call 50 calls, each getting small % 1 call, getting 100 %

9. 45 Mbps Results • Delay and jitter for EF not relevant because only small % of the packets for each call get through • For EF-ADMIT, delay and jitter are both below 1 ms, for both 1Q and 2Q • Introducing EF-ADMIT video has little effect on delay and jitter for both EF and EF ADMIT • Drop rate almost identical for 1Q and 2Q 1000 calls, each getting small % 10 call, each getting 100%

10. Conclusions • Simulation and analytical results confirm the expectations described in draft-ietf-tsvwg-admitted-realtime-dscp-00 • When EF traffic is properly policed, the EF-ADMIT traffic is protected from the effects (dropping, delay, jitter) of a major overload of EF (and AF, etc.) traffic • When EF traffic is properly policed, the 1Q and 2Q cases perform very similarly if all the and EF and EF-ADMIT is Voice (short packets) • When video (long packets) traffic is introduced to the EF-ADMIT traffic, delay and jitter suffer at 1.5 Mbps- little impact at 45 Mbps • These results demonstrate significant value in preserving EF-ADMIT performance even when overload significant causes degradation of EF performance. • In the context of essential network services for disaster response (as addressed in IEPREP), we conclude that EF-ADMIT can help ensure that disaster response service is assured under all circumstances.

11. Next Steps • Model other arrival rate and packet size distributions, for sensitivity • Evaluate the implications of mixing voice signaling traffic with voice bearer traffic in the same PHBs. • Address how to best to ensure video capabilities for disaster recovery under all circumstances. • Address disaster recovery data services, particularly in terms of how well the needs can be met by appropriate assignments within the framework of the existing AF classes. • Corroborate the event simulation and analysis results with a prototype implementation of the model configuration in the laboratory and testing the performance for the various scenarios. • Investigate sensitivity to variations in policing • Thank you for comments which contributed to -01 and Next Steps • Fred Baker • Ken Carlberg