1. doc.: IEEE 802.11-yy/xxxxr0 Submission January 2007 Yongho SEOK, LG ElectronicsSlide 1 Audio Video Multicast Protocol Notice: This document has been prepared to assist IEEE 802.11. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release: The contributor grants a free, irrevocable license to the IEEE to incorporate material contained in this contribution, and any modifications thereof, in the creation of an IEEE Standards publication; to copyright in the IEEE’s name any IEEE Standards publication even though it may include portions of this contribution; and at the IEEE’s sole discretion to permit others to reproduce in whole or in part the resulting IEEE Standards publication. The contributor also acknowledges and accepts that this contribution may be made public by IEEE 802.11. Patent Policy and Procedures: The contributor is familiar with the IEEE 802 Patent Policy and Procedures, including the statement "IEEE standards may include the known use of patent(s), including patent applications, provided the IEEE receives assurance from the patent holder or applicant with respect to patents essential for compliance with both mandatory and optional portions of the standard." Early disclosure to the Working Group of patent information that might be relevant to the standard is essential to reduce the possibility for delays in the development process and increase the likelihood that the draft publication will be approved for publication. Please notify the Chair as early as possible, in written or electronic form, if patented technology (or technology under patent application) might be incorporated into a draft standard being developed within the IEEE 802.11 Working Group. If you have questions, contact the IEEE Patent Committee Administrator at.http:// ieee802.org/guides/bylaws/sb-bylaws.pdfstuart.kerry@philips.compatcom@ieee.org Date: 2007-01-16 Authors:

2. doc.: IEEE 802.11-yy/xxxxr0 Submission January 2007 Yongho SEOK, LG ElectronicsSlide 2 Authors (cont.)

3. doc.: IEEE 802.11-yy/xxxxr0 Submission January 2007 Yongho SEOK, LG ElectronicsSlide 3 Motivations IEEE 802.11e –Provides Quality of Service support –But, AC_VO and AC_VI frames have high collision probability because of the small contention window AV Multicast Protocol in IEEE 802.11e –Difficult to provide Quality of Service because the collided frames are lost –Unfair channel access between AV multicast and AV unicast

4. doc.: IEEE 802.11-yy/xxxxr0 Submission January 2007 Yongho SEOK, LG ElectronicsSlide 4 Problem Definition Requirements of AVM –Quality of Service provision –Fair channel access between AV streams –Compatibility with IEEE 802.11 MAC –Multicast rate adaptation

5. doc.: IEEE 802.11-yy/xxxxr0 Submission January 2007 Yongho SEOK, LG ElectronicsSlide 5 1. Quality of Service Provision AVM should provide a recovery mechanism for corrupted frames Category of corrupted frames –Collision: AVM should support the retransmission of collided frames –Wireless channel error: AVM focuses on the semi-reliable multicast protocol because the multimedia traffic is a error tolerant

6. doc.: IEEE 802.11-yy/xxxxr0 Submission January 2007 Yongho SEOK, LG ElectronicsSlide 6 2. Fairness between AV Streams AVM should use the binary exponential backoff mechanism

7. doc.: IEEE 802.11-yy/xxxxr0 Submission January 2007 Yongho SEOK, LG ElectronicsSlide 7 3. Compatibility with IEEE 802.11 MAC The AV multicast frame should never be changed –Legacy IEEE 802.11 stations discard new packet formats such as the QDATA frame in IEEE 802.11e or A-MSDU frame in IEEE 802.11n

8. doc.: IEEE 802.11-yy/xxxxr0 Submission January 2007 Yongho SEOK, LG ElectronicsSlide 8 4. Multicast Rate Adaptation AVM should provide a rate adaptation mechanism –Current 802.11 MAC uses the fixed multicast PHY rate –The lowest multicast rate is the bottleneck of the WLAN performance 1 Mb/s rate A LAN Access Point server B WLAN 802.11b 11 Mb/s rate A

9. doc.: IEEE 802.11-yy/xxxxr0 Submission January 2007 Yongho SEOK, LG ElectronicsSlide 9 Related Works IEEE 802.11v TG –Just provides the simple multicast diagnostic capability 1) Multicast Diagnostic Request2) Multicast Diagnostic Report (Beacon Units) 3) Triggered Multicast Diagnostic Report

10. doc.: IEEE 802.11-yy/xxxxr0 Submission January 2007 Yongho SEOK, LG ElectronicsSlide 10 Proposed AVM Protocol Summary –Proposed AVM protocol is the leader based multicast protocol –A leader station for the multicast group transmits the ACK frame whenever it correctly receives the multicast frame AVM Protocol consists of –Leader Election Protocol –EDCA mechanism for Multicast –Multicast Rate Adaptation

11. doc.: IEEE 802.11-yy/xxxxr0 Submission January 2007 Yongho SEOK, LG ElectronicsSlide 11 Proposed AVM Leader Election Protocol –Leader Request Action frame –Leader Response Action frame –Leader Release Action frame CategoryAction Multicast Address Octets:1 1 6 CategoryAction Multicast Address Octets:1 1 6 CategoryAction Multicast Address Octets:1 1 6 Status Code 1

12. doc.: IEEE 802.11-yy/xxxxr0 Submission January 2007 Yongho SEOK, LG ElectronicsSlide 12 Proposed AVM Leader Election Protocol Leader Selection Algorithm –It is possible to utilize IEEE 802.11v multicast diagnostic capability –But, the specific algorithm is out of scope (a) Leader Request Action(b) Leader Response Action(b) Leader Release Action New LeaderOld Leader

13. doc.: IEEE 802.11-yy/xxxxr0 Submission January 2007 Yongho SEOK, LG ElectronicsSlide 13 Proposed AVM EDCA for Multicast –The multicast frame includes the correct Duration field for the NAV setting. –Leader sends ACK frame whenever it successfully receives the multicast frame Multicast DATA Unicast DATA ACK NAV Collision Binary Exponential Backoff Leader Non-leader

14. doc.: IEEE 802.11-yy/xxxxr0 Submission January 2007 Yongho SEOK, LG ElectronicsSlide 14 Proposed AVM Multicast Rate Adaptation –Multicast Diagnostic capability in 802.11v TG can provides a long-term solution for the multicast rate adaptation –Because the timescale of the multicast rate reporting is larger than the variation of the link quality variation –Additionally, AVM uses the rate adaptation mechanism similar to ARF, for the short-term solution

15. doc.: IEEE 802.11-yy/xxxxr0 Submission January 2007 Yongho SEOK, LG ElectronicsSlide 15 Summary The AV multicast applications such as IPTV are increasing But, a current multicast protocol in IEEE 802.11 wireless LAN has many problems AVM protocol is a proposal to improve the Quality of Service of Audio/Video multicast

16. doc.: IEEE 802.11-yy/xxxxr0 Submission January 2007 Yongho SEOK, LG ElectronicsSlide 16 Straw Poll #1 Is it necessary to consider a new AV multicast protocol in the 802.11 standard ? Yes: No:

17. doc.: IEEE 802.11-yy/xxxxr0 Submission January 2007 Yongho SEOK, LG ElectronicsSlide 17 Call for interest What should be the next steps:

18. doc.: IEEE 802.11-yy/xxxxr0 Submission January 2007 Yongho SEOK, LG ElectronicsSlide 18 Reference J. Kuri and S.K. Kasera, “Reliable Multicast in Multi-access Wireless LANs,” ACM Wireless Networks, 2001. D. Dujovne and T. Turletti, “Multicast in 802.11 WLANs: An Experimental Study,” in ACM MSWiM 2006. J. Villalon, P. Cuenca, L. Orozco-Barbosa, Y. Seok and T. Turletti, “Cross-Layer Architecture for Adaptive Video Multicast Streaming over Multirate Wireless LANs,” to appear in JSAC, 2007.