Virtual AP Requirements January 2005 doc.: IEEE 802.11-05/xxxx July 2005 Virtual AP Requirements DATE: July 2005 Author(s) Name Company Address Phone email Pat R. Calhoun Cisco Systems, Inc 170 West Tasman Dr., San Jose, CA 95134 408 853 5269 pcalhoun@cisco.com 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> Pat R. Calhoun, Cisco Pat R Calhoun, Airespace

January 2005 doc.: IEEE 802.11-05/xxxx July 2005 Abstract TGv has identified virtual APs as a possible requirement. This document proposed some requirements that could be adopted by the task group. Pat R. Calhoun, Cisco Pat R Calhoun, Airespace

Introduction July 2005 Most enterprise class WLAN devices on the market today support multiple SSIDs. This allows for segmentation of traffic over the air, extending a “VLAN-like” concept over 802.11. However, in order to maintain compatibility with 802.11 stations, these devices have a single BSSID per SSID supported. Consequently, these devices must transmit a beacon for every SSID. This creates two issues: Utilizes unnecessary air time Makes it impossible to distinguish a physical device from a logical device Pat R. Calhoun, Cisco

Terminology July 2005 Physical AP: An 802.11 access point advertising a BSSID (base BSSID) Logical AP: Any additional BSSID being advertised by a physical AP Generally increments off base BSSID, for instance base BSSID is 00:01:02:03:04:00, while first Logical AP is 00:01:02:03:04:01. Pat R. Calhoun, Cisco

Air Time July 2005 Imagine a scenario where an AP supports 5 SSIDs, with a beacon period of 100ms (default) In order to advertise its services, the AP must transmit five beacons every beacon period Assuming a basic data rate of 1Mbps, and a beacon size of 90 bytes, the average airtime for each beacon would be 800 usecs. Combining the beacons would eliminate the additional PIFS Pat R. Calhoun, Cisco

Virtual vs. Physical AP July 2005 Advertising more than a single SSID (hence BSSID) does not permit a STA to determine whether it is generated from a single physical device. (REDO) 802.11 extensions, such as 802.11k, could greatly benefit from knowing whether a BSSID is a physical vs. logical entity. Pat R. Calhoun, Cisco

Proposal Change the beacon format to combine multiple BSSIDs July 2005 Change the beacon format to combine multiple BSSIDs Reduces air time requirements Allows a STA to know about logical BSSIDs Pat R. Calhoun, Cisco

Question? July 2005 Pat R. Calhoun, Cisco