Lee Armstrong, Chair
Wayne Fisher, Editor
This Task Group will define enhancements to 802.11 required to support Intelligent Transportation Systems (ITS) applications.
WAVE is a mode of operation for use by IEEE Std 802.11™ devices in environments where the physical layer properties are rapidly changing and where very short-duration communications exchanges are required. The purpose of this standard is to provide the minimum set of specifications required to ensure interoperability between wireless devices attempting to communicate in potentially rapidly changing communications environments and in situations where transactions must be completed in time frames much shorter than the minimum possible with infrastructure or ad hoc 802.11 networks. In particular, time frames that are shorter than the amount of time required to perform standard authentication and association to join a BSS are accommodated in this amendment.
The P802.11p specification accomplishes the following:
• Describes the functions and services required by WAVE-conformant stations to operate in a rapidly varying environment and exchange messages either without having to join a BSS or within a WAVE BSS.
• Defines the WAVE signaling technique and interface functions that are controlled by the IEEE 802.11 MAC
This amendment to IEEE Std 802.11™ is based on extensive testing and
analyses of wireless communications in a mobile environment. The results of
these efforts were documented in ASTM E 2213-03, "Standard Specification
for Telecommunications and Information Exchange Between Roadside and Vehicle
Systems - 5.9 GHz Band Wireless Access in Vehicular Environments (WAVE) /
Dedicated Short Range Communications (DSRC) Medium Access Control (MAC) and
Physical Layer (PHY) Specifications". This document is available from:
ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA,
19428. This amendment to IEEE 802.11 is based on the ASTM E 2213-03 document.
Please see document, 11-07-2045-00-000p-Development of DSRC/WAVE Standards, (latest version) for additional information on the development of the amendment for WAVE.
Goals for March
2008: Complete comment resolution for LB110 and go to Letter Ballot
Comment resolution continued. Some resolution proposals were
initiated and discussed during the multiple Ad-Hoc teleconferences held before
the meeting. During the meeting, these were discussed with a number of motions resulting
in the creation of draft D3.05 being produced at the end of the meetings. At
the close of the meeting, it was found that there were a couple of comments
that were not formally resolved but these were considered to minor to worry
about (primarily simple editorial). The motion to move D3.05 to Letter Ballot
passed and a 30 day LB will begin as soon as possible after the meeting. Weekly teleconferences will continue (with a
probable delay in starting until initial LB results are received). A
face-to-face Ad_Hoc meeting
is planned for the week of April 29 in
Goals for January
2007: Complete comment resolution for LB110 and go to Letter Ballot
•
547 comments total
•
207 resolved prior to this week
•
410 resolved this week (some re-do from
previous meetings)
•
Essentially finished LB110 comment
resolution, a very small number not formally completed
•
Closed with Draft D3.03
Resolution of the 547 comments continued. There were a total of 207 comments resolved prior to the meeting, an additional 410 were resolved this week. Some comments were addressed more than once such as when the resolution of a comment required us to go back and reconsider a previous resolution. The TG is essentially finished with LB110 comment resolution (the operative word is “essentially” as Draft D3.03 which is the result of the meetings is felt to be ready for letter ballot in spite of a few random items that might still be addressed. Due to a lack of time, the TG did not get to reach a point where the importance of any remaining issues could be identified and discussed, thus there was no motion to go to Letter Ballot. Weekly teleconferences will continue to identify and propose resolutions to any remaining comments or issues.
Goals for
July 2007: Continue LB110 comment resolution
Comment resolution continued, with a total of 107 comments resolved this week. There were many more that were nearly ready.to vote on and complete, but time did not permit all submissions for presentation to be addressed. Weekly teleconferences will continue to develop additional resolutions.in preparation for the January meetings.
Goals for
July 2007: Begin comment resolution for LB110
LB110 failed by only two votes. Resolution of the 547 comments began with the primary order of activities being to get organized and prioritized. Major catagories of comments, mostly by clause number, were assiged to Individuals who would be responsible for them. About 100 were considered closed at the end of the week (mostly editorial). Weekly teleconferences would be held to work on the more difficult technical issues to be resolve.
Goals for
July 2007: Aapprove for Letter Ballot
All issues remaining from LB92 have been resolved and are reflected in P802.11p D2.06. The TG approved requesting that the WG proceed with a Letter Ballot of this draft with the goal of moving it towards sponser ballot.
Goals for May 2007: Resolve
Letter Ballot 92 Comments
The most significant remaining issue from LB92 (reflected in approximately 200 comments) had to do with the use of a WAVE announcement frame and not using an 802.11 beacon. Between the PAR and a large number of presentations, there had been ample explanation that conventional beacons could not provide the extremely short latencies required, this continues to come up.As a means of addressing these comments in a manner that would be most acceptable to the WG, a special form of beacon was approved which will be called an "on-demand beacon" and use the ordinary 802.11 beacon format. The task of preparing the explicit wording and incorporating this change into the draft was assigned and the resulting draft will be the basis for teleconferences as soon as it becomes available.
During the March meeting, 174 Comments addressed, 134 Comments Resolved. One proposal for resolving the many comments (over a hundred) regarding the use of a WAVE announcement instead of a beacon would use a slight modification to the beacon instead of the WAVE announcement. TGs is also considering a special beacon and we will investigate the potential of either a new WAVE beacon or a new beacon harmonized with TGs. Teleconferences will be held before the May meeting and a joint meeting slot with TGs will be held as part of this investigation.
Of the original 1060 comments, 649 remaining to be resolved.
Draft 2.01 is current working draft.
LB92 failed with 1060 comments received. The TG accepted Draft 2.0 as the working draft. The comments were organized by topic and assigned to individuals for resolution. About 500 considered simple editorial and assigned to editor to resolve. Established general principles for resolving most of the technical issues.
As a result of the approval of
Draft 1.3 at the September meeting and the editors directives for further
changes that were approved at that meeting, the editor had prepared a new draft
1.4. The Task Group started the session by voting to approve this new draft, Draft
802.11p_D1.4 as our working document. There were 7 presentations during the 4
session during the week, resulting in motions that resulted in additional
changes to be made to the draft. The
posted draft at the conclusion of the meeting, which includes all of the
week’s approved changes, is Draft 802.11p_D1.5. Feeling that this draft
represents the completion of comment resolution from LB81 as well as all
additional improvements identified since then, the TG moved to forward this
draft to the WG for Letter Ballot. The WG approved the motion and a Letter
Ballot will commence as soon as possible for this draft that will therefore be
renumbered to Draft 802.11p_D2.0.
An overview of CALM-related projects and standards
activities in
* Knut Evensen (part 1 PDF)
* Dr. Hans-Joachim Fischer (part 2 PDF)
* Knut Evensen (part 3 PDF)
* Dick Roy (VII) (part 4 PDF)
A ZIP file of the Powerpoint presentations is also
available
The Task Group started the session by using Draft
P802.11p_D1.1 as the working document. The previous Clause 20 was moved into
Clause 17 and Annex I and Annex J. The PICs were greatly simplified. As a
result of general improvements, the page count has gone from 59 to 35. The
extent of the additions and deletions made it unrealistic to use revision
marking in the new draft. The meeting minutes can be found in document
11-06-1556-01-000p-melbourne-september-2006-wave-minutes-doc-doc.doc. The
posted draft at the conclusion of the meeting was Draft 802.11p_D1.3.
The Task Group started
the session by voting to have the previous draft, P802.11p-D1.0, that failed to
receive the required 75% approval be the base draft for moving forward. The
group then began to formal comment resolution with discussion and motion on
Clause 20. There were 6 presentations during the 3 session during the
week. Teleconferences to continue resolving the comments from the letter
ballot. It is hoped that the revised draft will be ready for approval during
the September session.
The LB89 passed, allowing the letter ballot of draft D1.0 (LB 81) to begin. There were enough comments received during LB80 to develop and test our approach to comment resolution (borrowing heavily from other groups experiences). We evaluated approximately 20 LB80 comments during the week, verifying that TGp is ready to being responding to the many hundreds of comments expected on LB81. Because all of the LB80 comments that we worked on in March will also appear as LB81 comments, the resolutions agreed to will give us a head start for the next meeting. Some of the comments proposed changes to the draft that were generally agreed to in principle, but final judgment could not be given until the final explicit editor’s instructions are available. An ad-hoc group was formed to evaluate the impact of responding to these comments and report at the next meeting. This group will be conducting teleconference meetings over the next two months.
The draft D0.25 was reviewed, together with the comments received prior to the meeting. All remaining D0.24 and all new D0.25 comments were resolved. The editor will produce draft D0.26 (which will become D1.0 with a letter ballot) based on the resolutions to these comments.
The TG understood 802.11 policies and procedures
article 2.9.2 (specifically item 3) allowed going to letter ballot since the
current draft and all changes to it had been properly voted on and made
available to the WG. However, during the plenary, after making the motion to go
to letter ballot, item 4 was invoked: “Any voting member can bring a
motion requesting that, after the editor has completed the draft, work be
approved by a fifteen day confirmation letter ballot of the draft before
submission to WG letter ballot.”
It was then necessary to retract our motion for letter ballot and
instead make a motion to have a 15 day confirmation vote to be followed by a 40
day letter ballot if the confirmation passes. The confirmation vote can occur
only after the new draft .26 is available and the voting list has been updated
(which is at least 2 weeks from the end of the meeting).
The impact is that it is impossible to have any letter ballot results before the March meeting. Since the confirmation vote is simply a yes/no response, and the letter ballot will most probably have just started at the time of the March meeting, unless the unexpected happens, TGp will not meet in March.
The draft D0.24 was reviewed, together with the comments received prior to the meeting.
There were a total of 73 comments received for D0.24 and 19 remaining unresolved from D0.23 (some were withdrawn by the commenter, explaining the different count then what was reported last month). During the November meeting, all of the remaining D0.23 comments were resolved and 43 of those pertaining to D0.24. Several comments that were expected to be approved quickly instead produced lengthy discussion in the meeting which resulted in our failure to resolve all ballots and move the draft to the Letter Ballot stage.
The editor will produce draft D0.25 for posting and another round of comments solicited from the members. A teleconference is planned for December 13 to review proposed comment resolutions. Additional teleconferences may occur as needed before the January meeting. Notice of such teleconferences will be made using the 802.11 e-mail reflector. It is hoped that all comments can then be resolved in such a manner that the draft can be approved to go to letter ballot thereafter. Going to WG Letter Ballot in January 2006 does look like a high probability.
The draft D0.23 was reviewed, together with the comments received prior to the meeting.
There were a total of 107 comments received for D0.23, of these we were able to address 74 before we ran out of time. Of these, 65 were totally resolved, 9 addressed but still open. This left 33 comments that were not addressed.
As a result of addressing these comments, there are
a large number of discrete edits to the document. The extent of these changes,
plus the number of comments left unresolved, means that it will be at least
November before we can consider moving to Letter Ballot.
The editor will produce another draft for posting by
October 14. Additional comments are to be submitted to the editor no later than
November 4 so that they can be consolidated for discussion at the next
meeting. At least one teleconference is
expected before November to review proposed comment resolutions. Notice of such
teleconferences will be made using the 802.11 e-mail reflector. It is hoped
that all comments can then be resolved in such a manner that the draft can be
approved to go to letter ballot thereafter. Based on the experiences of the
past two meetings, the best estimate for going to WG Letter Ballot is now
January 2006.
The draft D0.22 was reviewed, together with the comments received prior to the meeting. Almost all of the comments were completely resolved but we ran out of time before completing them all. The WRSS carryover from the previous the meeting resulted in clarification and wording that satisfy the TG members. This should bring closure on this issue.
With resolutions identified for almost all comments, the editor will produce another draft for posting by August 5. Additional comments are to be submitted to the editor no later than September 5 so that they can be consolidated for discussion at the next meeting. It is hoped that all comments can be resolved in such a manner that the draft can be approved to go to letter ballot thereafter.
The draft D0.20 was reviewed, together with the 75 comments received prior to the meeting. Most of the comments were completely resolved but there were some that will require additional investigation to result in suggested modifcations to the document. The WRSS review that took place prior to the meeting failed to result in wording that would satisfy the TG members. An ad-hoc meeting during the week produced a clarification of what was causing the problem (an inability to succiently state the requirements), and an approach for satisfying another concern with WRSS which was the perceived advantages versus the benefits of this function. An action item for resolving this before the next meeting was assigned. Another action item was created to evaluate the relationship with 802.11j to verify that there are no inconsitencies between the two documents. The other issue that resulted in an action item was to resolve comments regarding testability of some parts of the specifications.
It is hoped that the resolution of these comments
will result in a draft which is suitable for WG ballot after the July meeting. The
next draft will be prepared and be available for TG commenting by June 13.
The draft D1.2 was not completed on schedule, thus the comments received prior to the meeting were not as extensive as was planned. Not all TG participants were able to submit comments prior to the meeting. There were a total of 129 comments received, of which 93 were completely resolved leaving 36 open to be resolved at the next meeting. After resolving all editorial comments that did not require extensive TG discussion, the comments were addressed in order of sensitivity or potential controversy that might be expected. The result is that we should be able to resolve the 36 open comments at the May meeting. Many of the comments were resolved by a decision to delete multiple clauses that do not properly belong in 11p as they are a part of a higher layer standard IEEE P1609. The result of these deletions is that the 11p document is considerably simplified.
There was one comment regarding the WRSS that will require additional discussion. A suggested rewording of this clause will be prepared and a teleconference will be scheduled for April 6 to discuss the proposed resolution of this comment.
It was verified that there is no problem or conflict with other aspects of 802.11 if the On-board units (OBUs) periodically changed their locally administered MAC address as a means of maintaining anonymity. Determining when and how to effect this change will be defined in the IEEE P1609.3 standard.
The two MAC enhancements originally proposed were a Cancel Transmit Primitive and a requirement that the MAC process only one packet at a time. The ad-hoc group met with teleconference on November 30 and were able to recommend that the Cancel Transmit Primitive would be useful and should be included in 11p, but that the one packet at a time requirement was not necessary and should not be considered. During the January 11p meeting, the TG decided to accept the ad-hoc group's recommendation.
A draft amendment was presented and is available on the web site. There were a number of initial comments that require TG discussion and approval (non-editorial). These were presented to the TG, discussed, and recommended modifications to the draft were identified for many of these. For those comments or open issues that could not be resolved during the meeting, an action item list was prepared that identifies individuals responsible for providing inputs to the editor and a schedule for completion of the revised draft in advance of the March meeting. The editor will post the revised draft at least one week before the next meeting and notify all TG members when this is done.
The editor was provided with specific input and requests for changes to the sample document that was presented at the meeting. The resulting document will then be posted as the 11p draft.
During the meeting, a proposal was made for two enhancements to the MAC. These are a Cancel Transmit Primitive and a requirement that the MAC process only one packet at a time. Discussion on this proposal indicated that additional investigation would be required. An ad-hoc group was created to complete this investigation and report back to the TG. A motion was approved that the WG permitting meetings of this ad-hoc group before the January meeting.
This page is maintained by Stuart J. Kerry and Lee Armstrong. Comments are welcome.
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