FILS Frame Content Date: 2012-11-01 Authors: February 2008 doc.: IEEE 802.11-07/2376r0 Date: Nov, 2012 FILS Frame Content Date: 2012-11-01 Authors: Liwen Chu, ST Liwen Chu, STMicroelectronics

Conformance w/ TGai PAR & 5C Nov 2012 Conformance w/ TGai PAR & 5C Conformance Question Response Does the proposal degrade the security offered by Robust Security Network Association (RSNA) already defined in 802.11? No Does the proposal change the MAC SAP interface? Does the proposal require or introduce a change to the 802.1 architecture? Does the proposal introduce a change in the channel access mechanism? Does the proposal introduce a change in the PHY? Which of the following link set-up phases is addressed by the proposal? (1) AP Discovery (2) Network Discovery (3) Link (re-)establishment / exchange of security related messages (4) Higher layer aspects, e.g. IP address assignment 1,2 Liwen Chu, ST

Non-HT Duplicate FILS Support Date: Nov, 2012 Non-HT Duplicate FILS Support Liwen Chu, ST

Non-HT Duplicate FILS in 802.11ai Date: Nov, 2012 Non-HT Duplicate FILS in 802.11ai 802.11ai allows an AP to transmit a duplicate FILS frame. (See below.) In the FILS frame content definition (11-12/1030), there are no indications of the primary channel nor the operating channel bandwidth. Problem: A STA that receives a duplicate FILS frame doesn’t know where to receive the beacon. Preamble Payload/FILS Advertisement Primary channel of the transmitter Preamble Payload/FILS Advertisement Preamble Payload/FILS Advertisement Preamble Payload/FILS Advertisement Slide 4 Liwen Chu, ST 4

Solution: Optional Primary Channel Indication in FILS Date: Nov, 2012 Solution: Optional Primary Channel Indication in FILS A Primary Channel field is added to FILS to indicate the 20MHz primary channel of the BSS: Operating Class (1 byte), Since the primary channel that is used to transmit beacon is always 20MHz channel. This can be removed. Channel Number (1 byte). A Primary Channel Present subfield (1 bit) indicates whether the FILS frame includes the Operating Class and Channel Number. When FILS is not transmitted in a non-HT duplicate PPDU, Primary Channel Present is set to 0. When transmitting a duplicate FILS frame, an AP can indicate the 20MHz primary channel by the Primary Channel field. A STA that receives FILS in a secondary channel can switch to the primary channel to receive the Beacon at the TBTT. Liwen Chu, ST 5

Multiple BSSID Support Date: Nov, 2012 Multiple BSSID Support Liwen Chu, ST

Multiple BSSID An AP device may support multiple BSSIDs (with .11v). Date: Nov, 2012 Multiple BSSID An AP device may support multiple BSSIDs (with .11v). Only one AP (the transmitted AP identified by transmitted BSSID) broadcasts beacons. Once an STA receives a beacon with Multiple BSSID IE, it can figure out the non-transmitted BSSID and the profile of the non-transmitted AP. Other APs in the same AP device define the operation of their networks through the non-transmitted profiles and the management information of the transmitted AP. A STA can associate with a non-transmitted AP. If a STA receives a FILS and decides that the SSID in FILS is not what the STA wants, the STA may sense another channel right away. Problem: In FILS a STA can’t figure out the networks identified by the non-transmitted BSSIDs. The STA may miss a BSS that it might want to associate with. Liwen Chu, ST 7

Solution: Multiple BSSID Indication in FILS Date: Nov, 2012 Solution: Multiple BSSID Indication in FILS A Multiple BSSID Present bit can be put in FILS frame, e.g. in FD Capability field. Once a STA receives FILS with Multiple BSSID Present being set to 1, the STA can select to receive the normal beacon or send a Probe Request. Or the content of the .11v Multiple BSSID IE can be a optional variable field in the FILS frame. Propose to use option 1. Liwen Chu, ST 8

Date: Nov, 2012 FD Capability Field Liwen Chu, ST

FD Capability Field in 11-12/1030 Date: Nov, 2012 FD Capability Field in 11-12/1030 Liwen Chu, ST 10

FD Capability Discussion Date: Nov, 2012 FD Capability Discussion The FD Capability field is for network selection and not for BSS operation. Most bits in Capability field are for BSS operation. They should not be in FD Capability, e.g. subfields in Capability field except Privacy subfield. dot11PHYType includes many old types which should not be in FD Capability. 2 bits should be used to identify the network type: 11b, 11a/11g, 11n, 11ac. Or, 2 bits should be used to identify the BSS capability: 20MHz, 40MHz, 80MHz, 160MHz/80MHz+80MHz. Or, their combination. Supported Minimum Rate field provides no help to BSS selection. What is helpful is the network’s maximum rate that is identified by the maximum data rate, or the combination of channel bandwidth, number of spatial stream, modulation, and coding rate). The most valuable items are channel bandwidth and number of spatial streams. Liwen Chu, ST 11

Updated FD Capability Option 1: Option 2: Date: Nov, 2012 Operation Channel Width PHY Type Nss (Number of Spatial Streams) Multiple BSSID Support Privacy IPv4 Support IPv6 Support Reserved 000: 20MHz 001: 40MHz 010: 80MHz 011: 160MHz 100: Reserved 101: Reserved 110: Reserved 111: Reserved 000: 11b 001: 11a/11g 010: 11n 011: 11ac 100: Reserved 101: Reserved 110: Reserved 111: Reserved 000: 1 001: 2 010: 3 011: 4 100: 8 101: Reserved 110: Reserved 111: Reserved Option 2: B0 B2 B3 B5 B6 B7 B8 B9 B10 B15 Operation Channel Width Nss (Number of Spatial Streams) Multiple BSSID Support Privacy IPv4 Support IPv6 Support Reserved 000: 20MHz 001: 40MHz 010: 80MHz 011: 160MHz 100: Reserved 101: Reserved 110: Reserved 111: Reserved 000: 1 001: 2 010: 3 011: 4 100: 8 101: Reserved 110: Reserved 111: Reserved Liwen Chu, ST 12

Updated FD Capability (Cont’d) Date: Nov, 2012 Updated FD Capability (Cont’d) Option 3: B0 B2 B3 B5 B6 B7 B8 B9 B10 B15 PHY Type Nss (Number of Spatial Stream) Multiple BSSID Support Privacy IPv4 Support IPv6 Support Reserved 000: 11b 001: 11a/11g 010: 11n 011: 11ac 100: Reserved 101: Reserved 110: Reserved 111: Reserved 000: 1 001: 2 010: 3 011: 4 100: 8 101: Reserved 110: Reserved 111: Reserved Option 2 is preferable since it is simple and conveys enough information (i.e. Bandwidth, and Nss) to describe the BSS PHY data rate. Liwen Chu, ST 13

Date: Nov, 2012 Straw Poll 1 Do you support to add 1-bit Primary Channel Present and optional 8-bit Primary Channel field in FILS frame? Yes No Abstain Liwen Chu, ST 14

Date: Nov, 2012 Straw Poll 2 Do you support to add 1-bit Multiple BSSID Present in FILS frame? Yes No Abstain Liwen Chu, ST 15

Straw Poll 3 Do you support option 2 of FILS Capability in slide 12? Date: Nov, 2012 Straw Poll 3 Do you support option 2 of FILS Capability in slide 12? Yes No Abstain Liwen Chu, ST 16