1. Air Efficiency and Reliability Enhancements for Multicast
Month Year
doc.: IEEE yy/xxxxr0
Air Efficiency and Reliability Enhancements for Multicast
September, 2006
Date:
Authors:
Notice: This document has been prepared to assist IEEE 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
Patent Policy and Procedures: The contributor is familiar with the IEEE 802 Patent Policy and Procedures < ieee802.org/guides/bylaws/sb-bylaws.pdf>, 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 Working Group. If you have questions, contact the IEEE Patent Committee Administrator at
S. Ponnuswamy, D. Stanley (Aruba Networks)
John Doe, Some Company

2. Month Year
doc.: IEEE yy/xxxxr0
September, 2006
Abstract
This proposal describes a mechanism to improve the Air Efficiency and Reliability of Multicast frames, supporting TGv objective # 2120.
S. Ponnuswamy, D. Stanley (Aruba Networks)
John Doe, Some Company

3. Goals Support transmission of multicast traffic at higher data rates
September, 2006
Goals
Support transmission of multicast traffic at higher data rates
Increase air efficiency
Provide a mechanism to increase reliability of multicast
STA delivers # frames between selected TSFs to AP
Re-use and extend FBMS mechanism and Multicast Diagnostic Report already adopted by TGv
S. Ponnuswamy, D. Stanley (Aruba Networks)

4. Approach The AP may transmit Multicast frames at higher data rates
September, 2006
Approach
The AP may transmit Multicast frames at higher data rates
Must be one of the supported rates of the AP and all members in the multicast group
The STA indicates the highest multicast rate that it can receive in the (re) association request or FBMS Request Action Frame
The AP indicates the multicast rate, multicast MAC address and diagnostic interval to the STA in the (re) association response or FBMS Response Action Frame
The STA uses the Multicast Diagnostics Report to report the number of multicast frames received between starting and ending TSF and the desired multicast rate. The AP may
Compare number of frames received by the STA to the number of frames it sent to determine frame loss rate of multicast stream
Adjust the rate and group membership as needed
The exact multicast rate adaptation method is not defined
S. Ponnuswamy, D. Stanley (Aruba Networks)

5. Optional TCLAS Processing IE
September, 2006
FBMS Request
STA sends request to AP with one or more FBMS elements
An FBMS Element contains one new field
TCLAS identifies L2 or L3 traffic
Delivery Interval is the number of DTIM intervals the traffic should be transmitted at
TCLAS IE
Optional TCLAS IE
Optional TCLAS Processing IE
Delivery Interval
Multicast Rate
Octets:
variable 3 1
—FBMS Element format
S. Ponnuswamy, D. Stanley (Aruba Networks)

6. Multicast Diagnostic Interval
September, 2006
FBMS Response
Each FBMS Status Element contains three new data items
FBMSID: Identifies the stream associated with the FBMS element at the AP
Element Status
Delivery Interval
Element Reason Code
FBMSID
FBMS Counter ID
Multicast Rate
Multicast Address
Multicast Diagnostic Interval
Octets: 1 6 4
S. Ponnuswamy, D. Stanley (Aruba Networks)

7. Multicast Diagnostic Report
September, 2006
Multicast Diagnostic Report
Minor modifications are made to the existing TGv Multicast Diagnostic Report to
Increase the measurement interval duration
Indicate that a report is being provided for multicast performance purposes
Add the sequence numbers from the first and last frames
Add the desired multicast rate
This information may be used by the AP to improve the reliability of multicast by estimating multicast frame loss at a specific receiver, and adjusting the rate and/or the multicast group membership, if needed.
S. Ponnuswamy, D. Stanley (Aruba Networks)

8. September, 2006
Multicast air-time
The benefits of transmitting multicast at higher rate is obvious
When multiple multicast streams exist, each stream may use a different rate
It is up to implementations to choose a multicast rate adaptation algorithm
Proposal includes explicit feedback in FBMS response and Multicast Diagnostic Report
Other mechanisms may be used to enhance the rate adaptation
S. Ponnuswamy, D. Stanley (Aruba Networks)

9. Legacy Interoperability
September, 2006
Legacy Interoperability
Legacy STAs will receive broadcast as today – no change
The new FBMS IE will be ignored by legacy STAs
When FBMS is supported, multicast uses the new FBMS mechanism.
If the multicast also uses the legacy scheme (i.e., sent at the lowest rate), there is no need to send it at a higher rate.
TGv-aware STAs should be able to use all the IEs defined by TGv
The new FBMS response, with dialog token, may be used to update the FBMS state of TGv capable STAs
S. Ponnuswamy, D. Stanley (Aruba Networks)

10. September, 2006
Motion
Motion: “Instruct the editor to include the changes in document r1-air-efficiency-and-reliability-enhancements-multicast into the TGv draft”
Mover/Seconder:
Result
Yes No
Abstain
S. Ponnuswamy, D. Stanley (Aruba Networks)

11. September, 2006
References
S. Ponnuswamy, D. Stanley (Aruba Networks)