Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)

1. Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [Suggestion and discussion about some issues] Date Submitted: [March 18, 2008] Source: [Chang Sub Shin, Soyoung Whang, Uncheal Jeong, Seongsoon Joo] Company [ETRI] Address [161 Gajeong-dong Yuseong-gu, Daejeon, Korea] Voice:[+82-42-860-1668], FAX: [+82-42-869-1712], E-Mail:[shincs@etri.re.kr] Re: [] Abstract: [suggest solution about WG letter ballet comments and discuss some issues ] Purpose: [resolve WG letter ballet comments] Notice: This document has been prepared to assist the IEEE P802.15. 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. <Chang Sub Shin>, <ETRI>

2. Suggestion and discussion about some issues ChangSub Shin, Soyoung Hwang, Uncheal Jeong, Seongsoon Joo ETRI <ChangSub Shin>, <ETRI>

3. Procedure of SES • Synchronization - After initialization, Mesh Coordinator Start Synchronization for SES - Transmission 2 Sync request command frameaccording to tree topology (WO, AO, Sync boundary, boundary synchronizer) - Every child node have to transmit sync reply command frame - Every child node synchronize with their parents - Mesh Coordinator and Every boundary synchronizer re-start to sync with their children device every wakeup interval - If parent node fail, its child node seek its potential sync parent node in the neighbor table and make new relationship value (sync parent, sync child) • Data Transmission in SES mode 2.1 Simple Data Transmission - Data Transmission in active duration 2.1 Reservation Data Transmission - Reservation request command frame in active duration - Reservation reply command frame in active duration - Data Transmission in inactive duration <Chang Sub Shin>, <ETRI>

4. Algorithm of synchronization (1/3) Parent nodes transmit 2 successive sync request frame to their children nodes according to tree topology If child nodes successfully receive 2 sync frame, Children nodes send sync reply frame to their parent nodes Child nodes synchronize with parent node using the time value of At1, Bt(Ct,Dt)1 and Bt(Ct,Dt)2 At2 At1 (3) Receive sync reply frame A A (1) Parent (2) At1 time value (4) Sync using At1, Bt1 and Bt2 B Bt2 Bt1 (4) Sync using At1, Ct1 and Ct2 C B C D Child Ct2 Ct1 (4) Sync using At1, Dt1 and Dt2 D Dt2 Dt1 <Chang Sub Shin>, <ETRI>

5. Algorithm of synchronization (2/3)- add error recovery (new proposal) If their parent node fail, its child nodes seeksync parent node among neighbor nodes (express its relationship in the neighbor table) Its child nodes try to sync with sync parent node If its child node successfully can receive 2 sync packet from sync parent node, the child node transmit sync reply packet to sync parent node (include information of requesting sync child) Sync parent node receive sync reply packet from its new sync child node. Sync parent node add relationship value to its neighbor table (sync child) <Chang Sub Shin>, <ETRI>

6. Algorithm of synchronization (3/3)- add error recovery (new proposal) 1 Sync parent 3 2 Parent 4 Sync child 5 9 6 7 8 <Chang Sub Shin>, <ETRI>

7. Scheme for network-wide synchronization (example) Level 0 Level 1 Level 2 Level 3 Level 4 Sync boundary <Chang Sub Shin>, <ETRI>

8. Reservation process in SES -1 (new command frame) Source Destination C 1 A 2 B 3 4 D Reservation Request A : B : Reservation Request C : Reservation Request D : Reservation Reply Mesh header Mesh Payload <Chang Sub Shin>, <ETRI>

9. Reservation & Data Tx process in SES Source Destination C 1 A 2 B 3 4 D Slot 0 Slot 1 Slot 2 Data (1) REQ (A) REQ Sleep Sleep Node (1) Data Data (2) REQ REQ (B) REQ Sleep Sleep Node (2) Data Data (3) REQ REQ (C) REP Listen Sleep Sleep Node (3) Data REQ REP (D) Listen Sleep Sleep Node (4) Ack Frame Active Duration Inactive duration Wakeup Interval <Chang Sub Shin>, <ETRI>

10. Reservation slot value • 2400–2483.5 MHz O-QPSK PHY : max 133 bytes • Preamble : 4 bytes • PHR : 1 bytes • SFD : 1 bytes • Max PSDU size : 127 bytes • Pure max Tx time => 4.256 ms (133 bytes) • Define default value of reservation slot unit : 625 symbols (10ms in 2.4) • We have to consider proper value in implementation • => how many (1 tx + 1 ack) times ? <Chang Sub Shin>, <ETRI>

11. Issue – Data purge function • There is no way for Mesh layer to support indirect communication • Don’t support beacon enable mode • Don’t support MLME-POLL primitive • Cannot support MESH-PURGE primitive • Delete MESH-PURGE primitive or Add Poll primitive • If we add poll primitive, we correct behavior of MESH-PURGE primitive • Delete indirect-tx of TxOptions in MESH-DATA.request primitve • Need to search for related text <Chang Sub Shin>, <ETRI>

12. Issue – Leave Primitive • There is no explanation of MAC layer behavior • If leave primitive use dissociation MAC primitive, we have to add MAC layer behavior • Otherwise, add a new command frame of leave • Revies 20 column 41page • no MCPS-DATA.comfirm <Chang Sub Shin>, <ETRI>

13. Issue - Reference model (others) IEEE802.11 IEEE802.15.4-2006 <Chang Sub Shin>, <ETRI>

14. Issue - Reference model (IEEE802.15.5) • Differentiate primitive and internal access point • merge data plane and management plane • Add interface to upper layer Upper Layer 802.2 LLC primitive (SSCS) DME MHSME SAP MESH SAP MLME SAP PLME SAP PD SAP MCPS SAP MESH Sublayer MLME MAC Common Part Sublayer PLME PHY Layer MHSME Internal access <Chang Sub Shin>, <ETRI>

15. Question • Don’t we need Sequence field in every command frame ? • How can we know duplicate command frame in mesh layer ? <Chang Sub Shin>, <ETRI>