Null Beacon Energy Conservation concept November 2006 doc.: IEEE 802.11-06/1461r1 November 2006 Null Beacon Energy Conservation concept Date: 2006-11-11 Authors: 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>. Peter Ecclesine, Cisco Systems Peter Ecclesine, Cisco Systems

November 2006 doc.: IEEE 802.11-06/1461r1 November 2006 Abstract Null Beacon Energy Conservation enhances standby time by letting stations get back to sleep sooner The enhancements are related to TGv Objective: Power Saving (Req. #2010). The text is aligned with P802.11-REVma/D9.0 and P802.11v-D0.04. Peter Ecclesine, Cisco Systems Peter Ecclesine, Cisco Systems

November 2006 Req 2010: Power Saving “TGv shall support one or more power saving schemes to optimize the STA’s power consumption during prolonged time periods of no transmission or reception activity in the order of several hundred’s of ms’s or above.” In every 24/7 week, probably 60 hours are not busy ;-) and when a STA is not transmitting much, it still needs to receive beacon frames from the Access Point Receiving and processing beacon frames is a substantial component of standby time power consumption Peter Ecclesine, Cisco Systems

November 2006 Overview [11.2] Power Management uses the Traffic Indication Map (TIM) in every AP beacon frame to indicate that buffered MSDUs are available to STAs that are in Power Save mode. [7.3.2.6] A ‘zero TIM’ is a six octet Information Element indicating no buffered MSDUs for any STA. Observation – Beacons have many elements to support association, and few to support Power Save Induction – if an alternate Beacon frame is defined, it can be used for overall energy savings Peter Ecclesine, Cisco Systems

Estimating Power Savings November 2006 Estimating Power Savings Must process PLCP header in any case Should process 26 octets of general frame Frame Control (2) , Duration/ID (2), three address fields (18), FCS Beacon frames have many additional elements – Table 26 plus an FCS (4) Timestamp (8), SSID (2-34), Supported rates (3), TIM (6-256), Country (8-256), Power Constraint (3), Supported Channels (4-256), Extended Rates (3-257), Extended Capabilities (3-257) Minimum power to process beacon frames could be ~ one half of today’s power consumption Peter Ecclesine, Cisco Systems

Null Beacon The Null Beacon indicates: November 2006 Null Beacon The Null Beacon indicates: Zero TIM: a TIM where the DTIM count is zero, and there are no buffered broadcast, multi-cast or unicast frames. No frame elements requiring action in the regulatory domain (e.g. no DFS Channel Switch Announcement) Helps with the wireless VLAN problem Sets of beacon frames for each VLAN means there are lots more beacon frames per second. Helps in home networks Multiple WLAN devices in use, many 24/7 Peter Ecclesine, Cisco Systems

November 2006 Operational behavior Null Beacon energy conservation should be used by all TGv compliant STAs in Infrastructure mode (A.4.4.1 PC12) Draft text is 06/1xxx Null Beacon Energy Conservation draft Peter Ecclesine, Cisco Systems

November 2006 Questions/Answers Peter Ecclesine, Cisco Systems

November 2006 Motion Move to accept 06/1xxxr0 normative text describing Null Beacon Energy Conservation for inclusion into the TGv draft. In favor: Not in favor: Abstain: Peter Ecclesine, Cisco Systems