1. Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)
Submission Title: Analysis of Wakeup Frame Based MICS Band Communications
Date Submitted: November xx, 2010
Source: Hind Chebbo, Dave Davenport, Jin-Meng Ho, Omeni Okundu, Grace Sung
Re: LB#55 comment resolution
Abstract: This presentation explains some technical issues of the unicast and multicast wakeup mechanisms based on Wakeup frames as described in IEEE P /D01, so as to help TG6 recognize and address them at the November session and thus generate a more technical sound draft D2.
Purpose: To generate a sound TG6 draft for recirculation ballot.
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 contributors acknowledge and accept that this contribution becomes the property of IEEE and may be made publicly available by P802.15

2. Review of Wakeup Frame Resolution
The following statements appear in lb55-d01p sorted-comments.xls as a resolution of all Wakeup frame related comments:
Wakeup frame will be extracted and new subclause created for Wakeup frame usage in non-beacon non-superframe mode of operation.
Subclause 7.8 will be re-written as well.
No rewrite has been posted yet, and hence the technical issues of the Wakeup frame based mechanisms remain unresolved.
These issues need to be resolved just as others do during this letter ballot comment resolution.

3. Review of Unicast Wakeup Frame Mechanism
The following text and figure are excerpted from TG6 D01:

4. Analysis of Unicast Wakeup Frame Mechanism
All unconnected nodes receiving a frame requiring I-Ack and with Recipient ID set to Unconnected_NID will send an I-Ack frame.
They do not parse the payload before sending an I-Ack frame.
This makes the wakeup mechanism no longer “unicast”.
Both Wakeup and Poll frames sent in Figure 75 have the Recipient ID set to Unconnected_NID.
An unconnected node does not have a Connected_NID yet.
Frames with unconnected_NID (as recipient NID) in the MAC header and IEEE MAC address (as recipient Address) in the payload cannot be considered unicast.
Poll frames do not have an IEEE MAC address in the payload anyway.
These are facts and defeat the intended unicast wakeup mechanism.
Wakeup and Poll frames cannot be used for unicast to unconnected nodes.
For connected nodes, the Recipient ID is set to a Connected_NID, and hence the full IEEE MAC address is not needed.
If timing information is needed, then a mode with superframe boundaries can be used, so can Poll frames for unicast wakeup.
Conclusion:
Unicast mechanism based on Wakeup frame are just not unicast mechanism.
Remove unicast wakeup mechanism based on Wakeup frames.

5. Review of Multicast Wakeup Frame Mechanism
The following text and figure are excerpted from TG6 D01:

6. Analysis of Multicast Wakeup Frame Mechanism
If timing information is needed, then a mode with superframe boundaries can be used, so can Poll frames for multicast wakeup, as illustrated in Figure 76.
Wakeup frames have a payload and lead to a less efficient multicast wakeup mechanism in terms of power consumption, access delay, and medium utilization.

7. Analysis of Multicast Wakeup Frame Mechanism
Wakeup frame based multicast wakeup mechanism uses a multicast NID in the MAC header.
 It already assumes a way to subscribe to a multicast NID
 Only nodes that need to have a wakeup will subscribe to that multicast NID; otherwise they would have an unwanted wakeup and additional power consumption
The NIDs in the payload are redundant, substantially increasing wakeup delay and wakeup overhead – at least 10 Wakeup frames need to be sent for each instance of multicast wakeup/lockup to allow nodes to cycle through all the MICS channels.
Without having the unicast mechanism, there is no rationale to create and define another multicast wakeup mechanism based on the Wakeup frame
Conclusion: Remove multicast wakeup mechanism based on Wakeup frames.

8. Summary
Our analyses show there are fundamental technical issues with the wakeup mechanisms based on Wakeup frames.
We have not been able to help come up with solutions.
We have not seen solutions submitted by the authors of those mechanisms or other participants – even at this time.
Submission of solutions at the meeting is not productive and extremely time consuming. Also review of solutions by Tg6 members is required before discussing and finalizing them. This leads to further delay and uncertainty of the whole process.
Our only option now is to remove the wakeup frame based mechanisms from the draft
Our objective for this meeting should be to produce a solid new draft for a recirc at the end of this meeting.

9. Motion
To remove the wakeup frame (not the poll frame) based mechanisms from the draft D01
Moved: Jin-Meng
Seconded: Hind Chebbo
Yes: 17
Abstain: 1
No: 9
Motion failed