doc.: ieee 802.11-01/274 submission may 2001 john m. kowalski et al, sharp. av multicast for...
TRANSCRIPT
May 2001
John M. Kowalski et al, Sharp.
Doc.: IEEE 802.11-01/274
Submission
AV Multicast for 802.11e:
Benefits/ChallengesSharp Corporation
John Kowalski
May 2001
John M. Kowalski et al, Sharp.
Doc.: IEEE 802.11-01/274
Submission
CONTENTS
• Multicast Applications• Limitations of Current & Draft
Standard• Requirements for AV Multicast• Options to meet this challenge• Discussion Points of AV Multicast• Summary
May 2001
John M. Kowalski et al, Sharp.
Doc.: IEEE 802.11-01/274
Submission
Multicast Application –1• For the Home Application, there are many AV
devices.• “1 to n” communication will be necessary
especially for the AV application. - e.g. Tuner and TV
TV on 2nd floor
TV in Living room
Mobile Viewer
BS/CS Tuner CATV STB
May 2001
John M. Kowalski et al, Sharp.
Doc.: IEEE 802.11-01/274
Submission
Multicast Application –2• For the Home Application,
Several AV devices will be used for realizing the one AV application. – e.g. Home theater System
Monitor
Stereo
DVD Player
Rear surround speaker
May 2001
John M. Kowalski et al, Sharp.
Doc.: IEEE 802.11-01/274
Submission
Multicast Application –3• For Office,
Multicast also might be useful. – e.g. Video conference System
Center Projector
VIDEO SharingWhite Board Sharing
May 2001
John M. Kowalski et al, Sharp.
Doc.: IEEE 802.11-01/274
Submission
Limitations of Current & Draft Standard
• Multicast groups need to be defined -that take advantage of 11e- in order to do true multicasting (as opposed to multiple synch’d streams)
• AND– Multicast is an unacknowledged service
(in 802.2)– BUT we need some ACK mechanism at
least in the near term.
May 2001
John M. Kowalski et al, Sharp.
Doc.: IEEE 802.11-01/274
Submission
Discussion Points of AV Multicast
• Groupcast address definition for AV Multicast– Which kind of address should be used?– How to make a standard?
• Grouping sequence– How to decide the address? HC? Image
source?– How does the ESTA join the group?– How to inform the group address?
May 2001
John M. Kowalski et al, Sharp.
Doc.: IEEE 802.11-01/274
Submission
Requirements for AV Multicast
• For realizing the AV application, the followings are required for the Multicast transfer.– Forward error correction (RS-code)– Delayed Acknowledgement– Retransmission mechanism
May 2001
John M. Kowalski et al, Sharp.
Doc.: IEEE 802.11-01/274
Submission
So what are our options? (1)
• Do nothing – Positive: We don’t have to do
anything.– Negative: We miss out on a huge
application market OR use multiple synch’d streams, which are horrendously inneficient.
May 2001
John M. Kowalski et al, Sharp.
Doc.: IEEE 802.11-01/274
Submission
So what are our options? (2)
• Work with 802.? to develop recommended practice for QoS enabled multicast groups with acknowledged service – Positive: Would provide a single
solution for all 802.X wireless systems. Long term solution
– Negative: Takes time. Problems with legacy equipment?
May 2001
John M. Kowalski et al, Sharp.
Doc.: IEEE 802.11-01/274
Submission
So what are our options? (3)
• Provide a solution that works for 802.11– Positive: Would harmonize well with work
going on to integrate 802.11 with AV/1394 systems. Could be done relatively quickly.
– Negative: Would have to provide an interface, and services that would not be conformant to current 802.2 standard.
May 2001
John M. Kowalski et al, Sharp.
Doc.: IEEE 802.11-01/274
Submission
So what are our options? (4)
• Use Transport Layer via IETF practices for Multicasting...– Positive: Would harmonize well with
work going on to integrate 802.11 with AV/1394 systems. Could be done relatively quickly.
– Negative: Can latency/jitter/buffer size requirements be met?
May 2001
John M. Kowalski et al, Sharp.
Doc.: IEEE 802.11-01/274
Submission
Summary
• We believe the AV multicast expands the wireless application market greatly for 802.11.
• We want to start the discussion about the AV multicast.
• Any help/additional options would be greatly appreciated.