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Response from a former IMPP Chair (Re: Last Call: A Model forPresence and Instant Messaging to Proposed Standard)

WRITTEN IN MY ROLE AS FORMER IMPP CHAIR

Dave and Marshall,

I have issues with your presentation of reality.
I am unable to see technical issues of real substance in your comments; the issues seem all to be procedural, and revolve around the missing update to the WG charter.
Since I was one of the WG chairs at the two IETF meetings immediately following the "group of nine" effort, I accept responsibility for this procedural error. The charter should have been updated.

However, I must take issue with some of your presentation of how the WG decided issues, as well as some of your specific issues.
In particular, your statement:

The problem with the group's dichotomy between end-to-end vs. gateway
goals was discussed repeatedly.  Only towards the end of the working
group's effort did this appear to become resolved -- in the direction of
an end-to-end content standard.  However, even then it was clear that the
few remaining participants in the group continued to hold very different
understandings of the goal.
is directly contradicting the minutes of the December 15, 2000 meeting of the WG in San Diego, which say:

ROOT: Should messages passed wround in CPIM-compliant
Q: do we think that we need to be able to pass around a pile of bits that
can be signed:
A: Rough consensus in the room (all but 1 raised hand yes)

Q: Should CPIM specify structure of this message?
A: All think it should specify the format.
The exact format was thereafter discussed in March 2001 and August 2001.
Because of (I believe) the failure of the editor to update the core CPIM document between February 2001 and November 2001, the group did not meet in December 2001; the format was discussed again in March 2002, July 2002, November 2002 and November 2002. At no time do the minutes record a decision of the group to revisit or reverse its decision to support a single format for interoperability.

For a further instance, consider this complaint:

How can "duration" have any useful meaning when there is no baseline
reference for the starting point or ending point of the duration and
when Internet exchange latencies are completely unpredictable? In other
words, when a participant receives a duration value from another
participant, what does it mean? Duration relative to what point of time?
We do not know how many seconds it took for the service data to reach
the receiving participant.
The decision to use intervals was a very visible one in the WG, and none of the minutes I have read show this decision being challenged at any working group meeting; indeed, instead we see long wrangles over the meaning of "duration = 0", which is hard indeed to express in a format that has a "baseline reference".
While I have not found this in the minutes, I believe the justification for using duration was the same as that used for the sysUptime in SNMP: That one should NOT require the elements of an IM system to have synchronized clocks.

A common thread running through the minutes of IMPP meetings is the perception that all major issues have been settled:

San Diego, December 1999:

The goal is that the group will finish its work and then go away,
hopefully before the next IETF.

London August 2001:


LD: We've reached some kind of closure on all major points; really hope
this will have been the last IMPP meeting (i.e., that we can wrap this
into revised & finished documents before the next IETF).
My conclusions:

The working group has suffered from very slow document updates, a bad error in judgment (mine) re charter update, and repeated re-raising of old closed issues (for instance, at Atlanta in November 2002, Dave Crocker could be heard re-raising the issue of the need for loop control, which the group had discussed and decided in December 2000, choosing hopcount as the preferred mechanism in March 2001).

However, I find the criticisms raised against the process leading to the forwarding of these documents to the IESG to be very much off target.

Harald Alvestrand
Speaking as a former chair of the IMPP group