1. doc.: IEEE 802.11-09/0072r0 Submission January 2009 Slide 1 Proxy ARP Issue for Direct Link Setup 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, 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 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.http:// ieee802.org/guides/bylaws/sb-bylaws.pdfstuart.kerry@philips.compatcom@ieee.org Date: 2009-01-19 Authors: Yongho Seok, LG Electronics

2. doc.: IEEE 802.11-09/0072r0 Submission Abstract The presentation describes a DLS setup issue when proxy ARP is used at QAP Yongho Seok, LG ElectronicsSlide 2 January 2009

3. doc.: IEEE 802.11-09/0072r0 Submission Proxy ARP in IEEE 802.11v (1/2) In IEEE 802.11v Draft 3.01 –Optional Proxy ARP Service Aim to reduce broadcasting ARP request messages in the wireless part Shall respond to the ARP request (IPv4) and ICMPv6 Neighbor Discovery (IPv6) on behalf of the non-AP STA Slide 3Yongho Seok, LG Electronics January 2009

4. doc.: IEEE 802.11-09/0072r0 Submission Operation Scenario –If QSTA1 has some data destined for QSTA2 Proxy ARP in IEEE 802.11v (2/2) Slide 4 QSTA1 IP1 QAP QSTA2 IP2 1a 2b 1b 2a 1a - ARP Request (Who is IP2 ?) 1b - ARP Response (MAC QAP is IP2) 2a - DATA (to MAC QAP ) 2b - DATA (to MAC QSTA2 ) Yongho Seok, LG Electronics January 2009

5. doc.: IEEE 802.11-09/0072r0 Submission Proxy ARP Issue for DLS (1/2) DLS Setup Request/Response frames –Require MAC addresses of DLS initiator and Peer STA But, if Proxy ARP Service is combined with DLS –DLS initiator should know Peer STA’s MAC address through ARP request or ARP cache before initiating Direct Link Setup However, DLS initiator regards QAP’s MAC address as Peer STA’s MAC address So, DLS initiator and Peer STA cannot exchange data directly after DLS setup is finished (or failed) –DLS cannot serve the purpose !!! Slide 5Yongho Seok, LG Electronics January 2009

6. doc.: IEEE 802.11-09/0072r0 Submission Proxy ARP Issue for DLS (2/2) Can we solve this problem by configuring Proxy ARP service at a QAP properly? –Option1) When an QAP receives an ARP Request from an associated STA with a Target IP Address that corresponds to another associated STA, the AP shall insert the other STA MAC address as the Sender’s MAC Address in the ARP Response packet. –Option 2) QSTA set Proxy ARP service field in Extended Capability IE to 1 for enabling Proxy ARP service for itself. Otherwise, sets it to 0 for disabling Proxy ARP service for itself. Slide 6Yongho Seok, LG Electronics January 2009

7. doc.: IEEE 802.11-09/0072r0 Submission Conclusion If Proxy ARP service is enabled, currently DLS may be not able to work STA supporting DLS needs a solution to bypass Proxy ARP service –Which Option is preferred ? Slide 7Yongho Seok, LG Electronics January 2009