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: [EGTS Joint Proposal for IEEE 802.15.4e] Date Submitted: [January 19, 2009] Source: [Myung Lee, Seong-Soon Joo, Tae Rim Park, Betty Zhao, Ghulum Bhatti, Ning Gu, Jie Shen, Wei Hong, Qin Wang] Address [] Voice:[+1-212-650-7260], FAX: [], E-Mail:[lee@ccny.cuny.edu] Re: [IEEE P802.15.4e] Abstract: [This document describes a joint proposal for IEEE 802.15.4e. While maintaining the backward compatibility to legacy IEEE 802.15.4b, the joint proposal meets all the MAC behaviors ratified by 802.15.4e TG. Currently, this joint proposal comprises contributions from CUNY, ETRI, Samsung, Huawei, MERL, Vinno, SIMIT, Arch Rock, USTB, Shenyang Inst. of Automation] Purpose: [Discussion in 802.15.4e Task Group] 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.

2. EGTS Subgroup Report CUNY, ETRI, MERL, Huawei, Samsung, Arch Rock, SIMIT, Vinno, USTB, SIA

3. Outline 1. Application support levels 2. Anticipated changes to 15.4-2006 STD 3. Backward compatibility description

4. Application Support Levels

5. Application Support Level • EGTS joint proposal can fully support all application domains because EGTS joint proposal can handle all required MAC behaviors.

6. Handling Required MAC Behaviors (1) • ACK • Secure and Robust ACK, Group Ack • Channel diversity (hopping, agility) • Adaptive Slot and Channel Allocation with Adjacent Channel Interference, Adaptive channel diversity, Optional distributed channel hopping • Superframe (GTS, TDMA) • Flexible and Backward-compatible Enhanced GTS, Embedded CFP • Low Power (Low duty Cycle) • Sampled Listening, CAP reduction, Optional inactive period • Overhead reduction (Short MAC address) • Distributed time slot and channel allocation, Distributed beacon scheduling, Embedded CAP, Reduced MAC header • Mesh support (Path diversity) • Tree and Mesh Support by EGTS structure

7. Handling Required MAC Behaviors (2) • Time synchronization (Relative, Absolute) • Time synchronization with deferred beacon • Resource Scheduling • Distributed EGTS allocation, Multiple QoS support, Sampled listening • Portability (Fast Assoc/disassoc, Associationless) • CAP, Localized channel allocation & Association • Beacon scheduling • Distributed beacon scheduling with beacon collision detection • Scalability • Distributed Approaches for resource scheduling, beacon scheduling • EGTS Joint Proposal also provides: • Reliability: EGTS Information Request, Embedded CAP, Deferred beacon • Backward Compatibility to 802.15.4 -2006 • Harmonious Coexistence with 802.15.4 -2006

8. Anticipated changes to 802.15.4-2006 STD

9. Summary of Anticipated changes • Modified / New MAC primitives • MCPS-DATA, MLME-GTS, MLME-EGTSinfo, MLME-START • New MAC PIB attributes • macMultisuperframeOrder, macConnecDev, macEGTSABT (Allocation Bitmap Table), macEGTSACT (Allocation Counter Table) • A new command frame • EGTS handshake • New fields in Beacon Payload • EGTS superframe descriptor, Beacon bitmap, TimeSync

10. EGTS-based Superframe Structure • A new MAC PIB attribute – macMultisuperframeOrder • We define MO (multi-superframe order) such that N = 2(MO – SO), where MO ≥ SO. • Multi-superframe Duration MD = aBaseSuperframeDuration*2MO symbols • A new sub-field in Beacon payload • EGTS superframe descriptor (variable) • Multi-superframeOrder (MO) (4bits) • GTS/EGTS flag (1bit) – 0: GTS, 1: EGTS • CAP_Reduction flag (1 bit) – 0: off, 1: on • CAP_Index (2 octets, only when the CAP_Reduction flag is on) • Embedded CAP/CFP flag (1 bit) • 0: Embedded CAP (Default) • 1: Embedded CFP • Number of Sub-slots (1 octet, only when Embedded CFP flag is on)

11. EGTS Scheduling (1) • A new parameter in a MAC Primitive • MLME-GTS.request (GTSCharacteristics, SecurityLevel, KeyIdMode, KeySource, KeyIndex, EGTSCharacteristics) • MLME-GTS.confirm (GTSCharacteristics, status, EGTSCharacteristics) • MLME-GTS.indication (DeviceAddress, GTSCharacteristics, SecurityLevel, KeyIdMode, KeySource, KeyIndex, EGTSCharacteristics) • A new command frame : EGTS Handshake • Sub-fields: MHR fields, Commands frame identifier, EGTSCharacteristics

12. EGTS Scheduling (2) • EGTSCharacteristics field format • EGTS Length (1 octet) : If this field is set to zero, the device operates the same way as the GTS in 15.4-2006 MAC. • EGTS Characteristics type (3 bit): Allocation, Reallocation (for channel diversity or duplicated allocation), Deallocation, Duplicated Allocation Notification, Suspend, Reduce, Restart • EGTS handshake type (2bit) : Request, Reply, Notify • Prioritized Channel Access (1 bit) : high priority, low priority • Destination Address (2 octets) • EGTS Slot Identifier (2 octets) • EGTS ABT Sub-block Length (4 bits) • EGTS ABT Sub-block Index (2 octets) • EGTS ABT Sub-block (variable)

13. ABT sub-block ABT Sub-block Index … … 00000000 00000000 00001000 00000100 00000000 00000000 00000000 01000000 00001000 00000000 00000000 00000000 01000100 00000100 00000000 00000000 00001000 00000100 00000000 00000000 00000000 01000000 00000000 00000000 10000000 01000000 01000100 01000100 00000000 00000000 00001000 00000100 00000000 00000000 00000000 01000000 10000000 00000000 00000000 00000000 00000000 00000000 10000000 00000000 00000000 00000000 … • Entire ABT (Allocation Bitmap Table) may be too big to be transmitted by Beacon or EGTS command frames • Example (MO = 7, SO = 3) • ABT size = 224 octets (representing 1792 slots) • 0: Vacant, 1: Allocated. • Row: time slot, Column: channel • Solution: • Send a ABT sub-block (with the index indicating beginning of the sub-block and the length of the sub-block) • ABT sub-block unit = 14 octets • (7 timeslot X 16 channels) • Example: 28 bytes sub-block. ABT Sub-block Length = 2 units ABT Sub-block Unit

14. EGTS Expiration, Deallocation, Reallocation • New MAC PIB attributes • macEGTSABT (Allocation Bitmap Table) • Explained in the previous slide • macEGTSACT (Allocation Counter Table) • ACT contains beacon interval counter of the slots that are allocated to the device (both as SRC and DST) • entry = (allocated slot ID, direction, beacon interval counter)

15. Allocation, Reallocation, and Deallocation Message sequence chartinitiated by a SRC device

16. Reallocation, and Deallocation Message sequence chart initiated by a DST device

17. Channel Diversity • Anticipated changes are already explained in the previous slides. • EGTS reallocation defined in the EGTSCharacteristics field of MLME-GTS primitive and EGTS handshake command frame. • Requested by higher layer for • Adaptive channel diversity • Periodic channel hopping

18. Beacon Scheduling • A new sub-field in Beacon payload • Beacon bitmap field • SD index (2 octets) : the index of current SD • SD bitmap length (2 octets) • SD bitmap (variable) • A new parameter in MLME-START.request • Add SDStartTime(2 octets), Beacon Schedule Flag (1 bit) • Optional: Disable the beacon scheduling and follow the instruction (SDStartTime) from a higher layer if the value of ‘beacon schedule flag’ is zero.

19. Time Synchronization • New subfields in beacon payload • TimeSync field • Timestamp (3 octets) • the time of sync parent’s local time. Is used to synchronize synch parent node. • Deferred beacon flag (1 bit) • 0: Disable deferred beacon , 1: Enable deferred beacon • Deferred time (1 octet) • length and indicates the number of aUnitBackoffPeriod

20. GTS Information Request • A new MAC primitive • MLME-EGTSinfo.request (CoordAddrMode, CoordPANId, CoordAddress, SecurityLevel, KeyIdMode, KeySource, KeyIndex) • MLME-EGTSinfo.confirm (EGTSCharacteristics, Timestamp, status) • A new MAC PIB attribute • macConnecDev • Indication of whether the device is a Connection Device. A value of TRUE indicates that the device is able to communicate in both beacon-enabled and nonbeacon-enabled mode.

21. Quality of Service • A new parameter in a MAC primitive • MCPS-DATA.request • extend TxOptions • (b0) 0: no Ack, 1: Ack • (b1) 0: CAP transmission, 1: GTS transmission • (b2) 0: direct transmission, 1: indirect transmission • (b3) 0 : CAP/GTS (15.4-2006), 1 : CAP/EGTS (15.4e): e.g, version control • (b4) 0 : Low Priority, 1 : High Priority

22. Backward Compatibility

23. Backward Compatibility • EGTS is backward compatible with 802.15.4-2006. • No changes on the existing frame formats • Only additions that are optional • New frame formats, primitives, and PIB attributes • New fields in the payload of Beacon

24. Coexistence • Minimal changes to the superframe structure. • EGTS can support the new features while harmoniously coexisting with the legacy devices (802.15.4-2006, 2003).