doc.: IEEE p Submission November 2004 Bryan Wells, DENSO LA LabsSlide p MAC Enhancement Proposals November r1 Bryan Wells DENSO INTERNATIONAL AMERICA, INC., LA Laboratories

doc.: IEEE p Submission November 2004 Bryan Wells, DENSO LA LabsSlide 2 Proposal to provide a Cancel Transmit primitive to the p MAC Proposal –Packets submitted to the MAC for transmission but not yet transmitted may be withdrawn. –Causes the MAC to abandon its attempt to transmit the current message, and reinitialize its operation in preparation for another transmit request. –Withdrawn packet may be re-queued or dropped by upper layer requesting the Cancel Transmit. Benefits –Provides enhanced QoS for high priority safety messages. –Prevents pending Tx requests from holding up required or desired channel switching. –Prevents packets from being Tx’d on the wrong channel.

doc.: IEEE p Submission November 2004 Bryan Wells, DENSO LA LabsSlide 3 Proposal for the p MAC to process only one transmit packet at a time Proposal –If the MAC receives a new packet for transmission while there is still a packet pending transmission in the MAC, the MAC will cancel the pending transmission and send the new packet. Benefits –Provides enhanced QoS for high priority safety messages. –Allows upper layers to override pending lower priority packet transmit requests with higher priority packet transmit requests.

doc.: IEEE p Submission November 2004 Bryan Wells, DENSO LA LabsSlide 4 Straw Poll Do you support the proposal to provide a Cancel Transmit primitive to the p MAC? Vote was not taken. Conclusion: TG consensus that this is relevant and necessary to investigate. Action Item: Document and present use cases and solution options for TG review. Post findings on the reflector for TG access. Use ad hoc meetings and/or teleconferences for TG discussion and resolution.

doc.: IEEE p Submission November 2004 Bryan Wells, DENSO LA LabsSlide 5 Straw Poll Do you support the proposal for the MAC to process only one transmit packet at a time; canceling pending packet transmit requests in favor of the new request? Vote was not taken. Conclusion: TG consensus that this is relevant and necessary to investigate. Need more feedback from e in order to determine how they handle this. Action Item: Investigate potential conflicts with e. Document and present use cases and solution options for TG review. Post findings on the reflector for TG access.