Managed BSS Channel Switch January 2003 IEEE 802.11-03/100r1 Managed BSS Channel Switch 2005-11-15 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 <http:// 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 <stuart.kerry@philips.com> 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 <patcom@ieee.org>. Kwak, Rudolf, InterDigital Submission

Kwak, Rudolf, InterDigital Outline Introduction TGh features for Channel Switch New TGv features for Channel Switch Protocol message sequence Frame contents Conclusions Kwak, Rudolf, InterDigital Submission

Kwak, Rudolf, InterDigital January 2003 IEEE 802.11-03/100r1 Introduction Interference and radar avoidance are motivators. Interference environments different for each STA is BSS. Measurements from all STAs on serving channel and alternate channels are relevant. STAs and network/AP may have different priorities in selecting alternate channel. Protocol described here is compatible with distributed and central control approaches. Complete normative text found in 05/1084r0. SMI – Structure of Management Information ASN.1 – Abstract Syntax Notation 1 Kwak, Rudolf, InterDigital Submission

TGh Features for Dynamic Frequency Selection (DFS) for Radar Avoidance Basic Request/Response collects info for radar sensing/detection (details unspecified). AP may use proprietary radar detection technique or may have a-priori radar knowledge. AP decides unilaterally on need for switch to avoid radar and time to switch. Channel Switch Announcement in beacon signals synchronized BSS channel switch Kwak, Rudolf, InterDigital Submission

New TGv Features built upon TGh functions Protocol permits AP/STA negotiation Any STA may initiate protocol when needed (optional) AP may poll all STAs for individual preferences (optional) AP decides to relocate BSS, selects channel and time for BSS switch AP may signal decision using TGh Channel Switch Announcement Each STA decides to follow BSS or to roam Each STA confirms operation in BSS on new channel. Protocol may be used to enhance TGh DFS to make better selection of new channel Kwak, Rudolf, InterDigital Submission

Message Sequence for BSS Channel Switch January 2003 IEEE 802.11-03/100r1 Message Sequence for BSS Channel Switch Other STAs AP STAx Channel Switch Solicitation Channel Switch Request[Query] Channel Switch Reports [Query] AP decides to switch and selects: new channel, switch time, response time Channel Switch Announcement Channel Switch Announcement Channel Switch Announcement Channel Switch Request[Confirm] SMI – Structure of Management Information ASN.1 – Abstract Syntax Notation 1 Switch Time Channel Switch Announcement Channel Switch Response Time Channel Switch Report(s)[did switch] Required elements in italics, others optional Kwak, Rudolf, InterDigital Submission

Channel Switch Solicitation Target Channel Number Regulatory Class Channel Switch Count Response Time Octets: 1 Sent by STA to suggest to AP that a channel switch is needed. (optional) Usually based on degrading local conditions Contains: Channel spec, as usual Suggested time for switch Latest time for AP to reply, usually well before the suggested switch time. Kwak, Rudolf, InterDigital Submission

Channel Switch Request Target Channel Regulatory Channel Channel Response Time Response Number Class Switch Switch Count Count Randomization Request Type Interval 1 1 1 1 1 2 Sent by AP to STA(s) to query conditions at STA locations for possible channel switch, or to command a BSS channel switch Query request permits negotiation of selected channel with STAs Contains: Channel spec, same as TGk Request Type = Query (negotiation) or Confirmed (execution) Switch count counts down to intended channel switch time Response time counts down to latest time for STA to reply Randomization to spread replies when broadcast Kwak, Rudolf, InterDigital Submission

Kwak, Rudolf, InterDigital Channel Switch Report Sent by STA in response to Channel Switch request May contain alternate channel suggestion based on STA local conditions. Contains: Channel spec, as usual Response code which is a function of the request type Kwak, Rudolf, InterDigital Submission

Channel Switch Response Codes Response Definition for Query Request Type Confirmation Request Type Reporting STA will not switch to the requested channel. not allowed 1 Reporting STA is able to switch to the requested channel at the requested time and will do so when this channel switch request is confirmed or when a this channel switch is announced. Reporting STA has switched to the requested channel at the requested channel switch time. This response is sent as the first transmission on the requested channel after the requested switch time. 2 Reporting STA will not follow, but would follow on the Alternative Channel Number. not allowed. 3 requested time and may do so if this channel switch request is confirmed or when a this channel switch is announced. 4-255 reserved Kwak, Rudolf, InterDigital Submission

Message Sequence for BSS Channel Switch January 2003 IEEE 802.11-03/100r1 Message Sequence for BSS Channel Switch Other STAs AP STAx Channel Switch Solicitation Channel Switch Request[Query] Channel Switch Reports [Query] AP decides to switch and selects: new channel, switch time, response time Channel Switch Announcement Channel Switch Announcement Channel Switch Announcement Channel Switch Request[Confirm] SMI – Structure of Management Information ASN.1 – Abstract Syntax Notation 1 Switch Time Channel Switch Announcement Channel Switch Response Time Channel Switch Report(s)[did switch] Required elements in italics, others optional Kwak, Rudolf, InterDigital Submission

Kwak, Rudolf, InterDigital Conclusions Protocol and frames defined to permit negotiation of new channel and switch time Compatible and builds on existing TGh capability Useful for distributed and central control approaches Similar to load balancing protocol (05/1064) with use of query/confirm request types Kwak, Rudolf, InterDigital Submission

Vote for Inclusion into TGv Draft Move to instruct the editor to include normative text for Managed BSS Channel Switch in 05/1084r0 into next version of TGv Draft. Moved by Joe Kwak Seconded __________ YES_______ No________ Abstain _____ Kwak, Rudolf, InterDigital Submission