March 2004 Jay Bain, Fearn Consulting; Knut Odman, Motorola doc.: IEEE /0142r0 Submission Project: IEEE P Working Group for Wireless Personal Area Networks (WPANs) Submission Title: Broadcast to Broadcast CTAs (multiple CAPs) Date Submitted: 16 March, 2004 Source: Jay Bain Company: Fearn Consulting Address: 703 Owens Drive, Huntsville AL Voice: , FAX: , Source: Knut Odman Company: Motorola Address: Mail stop VA18, 8133 Leesburg Pk, Vienna VA Voice: , Abstract: Discussion and recommendations on MAC to improve responsiveness. Purpose: For information Notice:This document has been prepared to assist the IEEE P 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 acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P802.15

March 2004 Jay Bain, Fearn Consulting; Knut Odman, Motorola doc.: IEEE /0142r0 Submission Problem definition Management response time can be excessive for many applications – Time to associate and be payload ready – Time to do dynamic CTA changes Less then efficient asynchronous communication peer-to-peer probe operation not supported in MCTA

March 2004 Jay Bain, Fearn Consulting; Knut Odman, Motorola doc.: IEEE /0142r0 Submission Solution idea Additional opportunities for communication within a given superframe –Multiple CTAs similar in functionality to CAP Support for peer-to-peer MCTAs Implementation via PNC placing BcstID as SrcID and DestID in CTA IE blocks Use stream index to further refine as described later

March 2004 Jay Bain, Fearn Consulting; Knut Odman, Motorola doc.: IEEE /0142r0 Submission Management CTAs- Current and proposed FunctionSrcIDDestIDStream index Open MCTA (obsolete?) BcstID(FF)PNCID(00)Management stream index Association MCTA UnassocID (FE) PNCIDManagement stream index Mgmt downPNCIDReg. DEVID (1:EC) (+FF ?) Management stream index Mgmt upReg. DEVIDPNCID (+FF?) (+Reg DEVID?) Management stream index New more open MCTA slotted Aloha BcstID Management stream index (FD) New CTA CAP CSMA/CA BcstID Async stream index (00)

March 2004 Jay Bain, Fearn Consulting; Knut Odman, Motorola doc.: IEEE /0142r0 Submission Other considerations for following slides Slotted Aloha and CSMA/CA Pseudo-static and dynamic CTA Carryover of CSMA/CA backoff Who can talk – relationship to CAP control bits (three bits)

March 2004 Jay Bain, Fearn Consulting; Knut Odman, Motorola doc.: IEEE /0142r0 Submission Slotted Aloha and CSMA/CA PHY calls for use of CSMA/CA and CAP Optional MCTAs call for use of slotted aloha method Alt-PHYs determine method to use Suggest retaining both schemes in this project

March 2004 Jay Bain, Fearn Consulting; Knut Odman, Motorola doc.: IEEE /0142r0 Submission Pseudo-static and dynamic CTA The new CTA CAP should be given the same robustness as currently defined by pseudo-static CTAs This allows use of CTA CAPs in the event that 1 to n (up to 4) beacons are corrupted. Current rules are followed.

March 2004 Jay Bain, Fearn Consulting; Knut Odman, Motorola doc.: IEEE /0142r0 Submission Carryover of CSMA/CA backoff Several CAPs may be present that are each of fairly short duration The current CSMA/CA backoff should carry to other CTA CAPs in a given superframe and otherwise follow the current rules for backoff (8.4.2) This requires further consideration !!

March 2004 Jay Bain, Fearn Consulting; Knut Odman, Motorola doc.: IEEE /0142r0 Submission Who can talk – relationship to CAP control bits (three bits) Current CAP has three control bits – – Association – Commands – Data Consider that either CTA CAPs behave as if all three bits are set, or that the command and data bits are set since association can be done in MCTA.

March 2004 Jay Bain, Fearn Consulting; Knut Odman, Motorola doc.: IEEE /0142r0 Submission Conclusion The problems stated are resolved with the approaches outlined Further discussion on several points are required Additional issues/comments??