1. doc.: IEEE 802.11-11-1250-00-00ai Submission Paul Lambert, Marvell TGai Discovery Proposal Author: Abstract Short high-level proposal for discovery techniques September 2011 Slide 1

2. doc.: IEEE 802.11-11-1250-00-00ai Submission Discovery - Background Current 802.11 Discovery –Passive scan (listen for beacons) –Active Scan (probe request/response) –11u action frames Issues –Fast scanning with probes can flood network (Yunoki-san 11-11-1414) –Broadcast probe has many responses –Passive scan is much slower than active –802.11 leaves scanning process (active versus passive) as vendor option. Most clients use active scanning to facilitate faster overall scan. September 2011 Slide 2 Paull Lambert - Marvell

3. doc.: IEEE 802.11-11-1250-00-00ai Submission Discovery Requirements Requirements –Discovery should be focused on what is meaningful for actual connectivity Available services Ability to authenticate successfully Probes should not be sent immediately without some determination of the contention environment –Pre-association discovery should provide clear interoperability requirements Definition of a service should –Responses to discovery requests should be fast ANQP 4 step exchange is not appropriate for basic discovery

4. doc.: IEEE 802.11-11-1250-00-00ai Submission Service Discovery Requirements Requirements –Pre-association messages should provide just enough information to ensure that a particular service/application will work No need to provide all capabilities or any negotiation –Detailed negotiation and capability determination can be post association Existing protocols for L3 service discovery and capabilities exchanges More secure to defer capabilities to post-association –Pre-association discovery should provide clear interoperability requirements –Extensible Allow addition of new services, but with guidelines that encourage interoperability Some services can map directly to a certification program by Wi-Fi

5. doc.: IEEE 802.11-11-1250-00-00ai Submission Basic Proposal Improve legacy discovery –Modify existing behavior of active scanning Require FILS devices to pause before using active probing. Possibly examine environment/contention to determine to use of probe. –Modify existing passive scanning to use promiscuous information (e.g. use probe responses directed to other MACs) Define improved discovery –Use public action frames to differentiate from use of probes –Provide container for simple service and authentication capabilities –Action frame based discovery should have clear back-off rules to prevent flooding

6. doc.: IEEE 802.11-11-1250-00-00ai Submission Extended Proposal Discovery of multiple APs –Provide a means for one AP to provide information about a neighborhood of APs –Define format for a list of APs: Identifying information for AP –What should this be? Location Band, etc –Neighbors may be filtered based on Ability to authenticate Availability of services or capabilities

7. doc.: IEEE 802.11-11-1250-00-00ai Submission Identifying Information for Discovery For pre-association discovery, the most important information to learn is: –Can a STA be authenticated with the AP –SSID is inadiquate 11ai should include a definition of the authentication domain(s) associated with a AP Discovery should be focused on: –Authentication domain or similar construct –Required services

8. doc.: IEEE 802.11-11-1250-00-00ai Submission Questions and Comments?