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[RE] New version of timing/synch PAR and Fw: Possible PARs  (with content, this time!)

Mick provided comments on the scope for the draft timing/synch PAR.  I have prepared a revised version that incorporates his comments, with several minor changes, and Michael has posted it at:
The minor modifications I made are (refer to the 2 sentences for the scope in Mick's email, attached below):
- in the first sentence, I added the word "concepts" after 1588; this is so that people would not assume we are using 1588 in its exact form as is with no changes (e.g., so people will not think we
have decided to use the one-way messaging with less frequent two-way messaging scheme in 1588, as opposed to the possibility of pure two-way messaging)
- in the first sentence, I changed audio and video to "time sensitive"
- in the 2nd sentence, I added the phrase "during normal operation and" after the words "... maintenance of synchronized time"
The only change to the  revised draft PAR is in the scope VG; the rest is the same as the previous posted version.
I would like to discuss this in the call this week.  Any comments are welcome.
Best regards,
Geoffrey M. Garner
Samsung (Consultant)

----- Original Message -----
Sent: Monday, November 07, 2005 12:31 PM
Subject: Re: Possible PARs (with content, this time!)

I am replying without the benefit of the original to hand. However I was thinking of the Scope as something like the following ...
"This standard will specify the use of IEEE 1588 in the context of IEEE Stds 802.1D and  802.1Q with particular reference to meeting the synchronization requirements for  audio and video applications across Bridged and Virtual Bridged Local Area Networks."
Someting as short as that. Of course the above is just my understanding of matching the problem statement, but I think it is clear that 802.1 (with the inclusion of the ResE folks) is uniquely qualified to specify the above.
To the above might be added as single statement about the grandmaster redundancy problem.
"It specifies the protocol and procedures used to ensure maintenance of synchronized time following addition, removal, or failure of network components and network reconfiguration."

"Geoffrey M. Garner" <> wrote:
Thank you for your comments on the timing/synch draft PAR.  I gather that you reviewed the initial, text version I had prepared.  Since then I prepared a VG form, as I was told that it is customary to prepare the initial draft PAR in the form of VGs to present to the WG.  The draft VGs were discussed in the ResE call last week (Oct. 26), and I received a number of comments.  I then incorporated the comments.  The revision is posted in the ResE area, at
(note that the parent page seems to not yet have a link to this, but the file is posted there.)
I began thinking about your comments in the next to last paragraph of your email.  I can add a reference to 1588 in the first bullet item of the scope.  For your items (1) - (3) that follow, it is not clear to me how to add this and still keep the scope concise (as it is a fair amount of material).  Do you have any suggestions on how to specifically word this (i.e., specific text) to keep the scope concise.  If so, I can prepare a revised version before the November meeting (if you have suggested text, could you also copy the 802 ResE exploder so that those who participated in the discussions so far can also give their opinions before I prepare the new draft).  However, I can wait to discuss this at the meeting if that would be better.
I also prepared a draft 5 criteria, in VG form.  The latest posted version is available at:
However, this was discussed in the ResE call this week (Nov. 2), and I have sent Michael the revision with the comments from the call incorporated.  I don't think it is posted yet.
Best regards,
Geoffrey M. Garner
Samsung (Consultant)
----- Original Message -----
Sent: Wednesday, November 02, 2005 6:19 PM
Subject: RE: Possible PARs (with content, this time!)

I'm sorry I have been unable to respond and have been much taken up with family issues, and will continue to be right up to the meeting. My first reactionis, as Paul says, these need to be much much shorter. 5 lines in 12 point Courier max. That doesn't mean to say that you shouldn't have a long version for working group reference, just that we need a very short version for the PAR proper. You may want to look at some recent PARs in the docs2005 public documents folder on the 802.1 website.
Another procedural point is that the contents of the scope clause ought to be close to a cut and paste of the initial part of the final scope clause in the standard. This is because RevCom, the committee that finally procedurally approves a proposed standard after all the ballots are done likes to ensure that the scope of the proposed draft really does fit the scope of the PAR that was approved. I think it is easiest to make this point using an example.
 Here is the Scope in the PAR for MAcsec (P802.1AE):
"Scope of Proposed Project:

The scope of this project is to specify provision of connectionless user data confidentiality, frame

data integrity, and data origin authenticity by media access independent protocols and entities that

operate transparently to MAC Clients**. Key management and the establishment of secure

associations is outside the scope but will be referenced by this project. **As specified in IEEE

Standards 802, 802.2, 802.1D, 802.1Q, and 802.1X."

Here is the beginning of the Scope clause for P802.1AE as it went to sponsor ballot:

"1.2 Scope

The scope of this standard is to specify provision of connectionless user data confidentiality, frame data

integrity, and data origin authenticity by media access independent protocols and entities that operate

transparently to MAC Clients.

NOTE-The MAC Clients are as specified in IEEE Standards 802, 802.2, 802.1D, 802.1Q, and 802.1X.

To this end it

a) Specifies ......"

You get the idea.

This all being said I think you may be able to trim what you have already fairly easily.

In addition to these items (Scope, Purpose, Reason) for the PAR form you need (this is an 802 rule not an overall IEEE rule) to put together a set of the 5 criteria. I am sure many of you are already familiar with the style of these for 802.3, and there are (again) specific examples in the .1 docs2005 directory.

At a higher level I think the PAR for the timing and sync can be fairly clearly developed. Perhaps a little more imaginative study of GSRP versus "RSVP-lite" (whateve that could be taken to mean) is going to be required to convince people that we can't start by chopping RSVP down to size (I am not saying this is a technical point of view by the way).

In the PAR for timing and sync I think it would be useful to consider the role IEEE 1588 plays in this, and in particular to consider whether there should not be a firm reference to IEEE 1588 even in the first sentence or two of the scope. The role of 1588 in this will become apparent in answering 5 Criteria questions anyway, so it is as well to play it up as to conceal it at the top -level. That then focuses on the value that the proposed adds to IEEE 1588 - in terms of making it useful in the context of bridge local area networks. This then expands into thoughts aboput how 1588 is applied (1) to the bridge architecture (2) to timing considerations related to the 802.3 MAC, or probably more likely to a timing reference point as close as possible to an arbitrary MAC (3) to the issues we discussed in the San Jose interim about having a proper grandmaster redundancy and distribution scheme (similar to spanning tree or other).

While it would be good to realize some alignment with 802.11 I would very much caution that admission control and admission control choices in advanced .11 network discussions are likely to be very much dominated by consideration that don't apply to this project, and that we could easily find the whole thing derailed by a massive increase in scope, without actually meeting anyone's needs, or indeed achieving any better conceptual alignment. I would sum it up in ancient map maker's terms "there be dragons".


-----Original Message-----
From: Michael Johas Teener []
Sent: Tuesday, October 25, 2005 4:22 PM
To: Mick Seaman; Paul Congdon
Cc: Yongbum Kim; Feifei Feng; Geoffrey M. Garner; Kees den Hollander; Jim Battaglia
Subject: Possible PARs (with content, this time!)

The ResE group (have to pick a better name! AV802?) has been thinking about PAR content over the past two weeks, and here are some examples. We'd really like to get some input from you two, if possible ...

BTW, some of the CE firms working with 802.11 are looking at their current QoS proposals and wondering if the admission control system that we are working on might apply to their A/Ps as well. Maybe there is a possibility to get the wireless people to work together with 802.1 (finally!).

         Michael D. Johas Teener -
office +1-408-922-7542 cell +1-831-247-9666 fax +1-831-480-5845 - PGP ID 0x3179D202