Frame-Specific Retry Limit for Intra-Stream Prioritization

1. Yacine Ghamri-Doudane et al. Frame-Specific Retry Limit for Intra-Stream Prioritization Authors:

2. Yacine Ghamri-Doudane et al. Abstract • This proposal fulfils two of the PAR objectives of the 11aa task group: • Graceful degradation of audio video streams when there is insufficient channel capacity, by enabling packet discarding without any requirement for deep packet inspection, • Intra-Access Category prioritization of transport streams by modifying EDCA timing and parameter selection without any requirement for deep packet inspection This proposal enables a STA to specify a frame specific retry limit using the Intra Acess Priority field and ADDTS/SCS configuration frames

3. Yacine Ghamri-Doudane et al. History • Stream Classification Service • IEEE 802.11-09/0725r1 • Implementation for Intra-AC Differentiated Services • IEEE 802.11-09/0022r0 • Using packet drop precedence for graceful degradation • IEEE 802.11-08/0764r1

4. Yacine Ghamri-Doudane et al. Use Cases • Prioritize some packets in a video stream when the media is busy • Give a better chance for important packets to be delivered • Some packets are more important than other(I-frames vs P-frames, B-frames or SVC improvement layers) • More retry limits than with DEI to make difference between I, P, B frames and additional SVC layers • STA can adjust (dynamically) the retry count without the need to change the AP configuration

5. Yacine Ghamri-Doudane et al. Simulation AP Video Stream Video Stream Non-AP STA Wired source node which sends the video stream AP forwards video stream to a STA and applies different retry limits on packets Non-AP STA receives video stream and evaluates it Ad-hoc nodes are hidden from the AP and disturbs the reception of the non-AP STA Bulk transfer

6. Yacine Ghamri-Doudane et al. Simulation results (1) = D:7 (2) = D:7 I:9 P:6 B:3 (3) = D:7 I:12 P:7 B:4 (4) = D:7 I:12 P:8 B:4

7. Yacine Ghamri-Doudane et al. Frame Retry Limit • Used by STA to prioritize important packets • Integration with ADDTSPEC and SCS configuration services • Extension of the Intra-Access Priority Field

8. Yacine Ghamri-Doudane et al. Example AP AV Stream AV Stream Non-AP STA AP uses SCS to classify packets and determine which Retry Limit it should apply to packets SCS Requests Source device tags UDP packets using DiffServ Wired connection to AP. Non-AP STA sends SCS requests to specify retry limits for each frame types according to their importance

9. Yacine Ghamri-Doudane et al. Another example AP AV Stream AV Stream Non-AP STA AP setup TSPECs to classify packets and determine which Retry Limit it should apply to packets Source device tags UDP packets using DiffServ Wired connection to AP. Non-AP STA receives important packets and other ones if possible

10. Yacine Ghamri-Doudane et al. Conclusion • This proposal fulfils two of the PAR objectives of the 11aa task group: • Graceful degradation of audio video streams when there is insufficient channel capacity, by enabling packet discarding without any requirement for deep packet inspection • Less important packets are discarded more quickly • Intra-Access Category prioritization of transport streams by modifying EDCA timing and parameter selection without any requirement for deep packet inspection • More important packets are kept while less important ones are dropped when channel is full

11. Yacine Ghamri-Doudane et al. Motion • Move to incorporate the text changes in 11-10-XXXX-00-00aa-frame-specific-retry-limit-normative-text.doc into the TGaa draft • Moved: • Seconded: • Result:

12. Yacine Ghamri-Doudane et al. References • 11-10-XXXXr0 “Frame-Specific Retry Limit for Intra-Stream Prioritization” • 11-09-0725r1 “Stream Classification Service” • 11-09/0022r1 “Implementation for Intra-AC Differentiated Services” • 11-08/0764r1 “Using packet drop precedence for graceful degradation”