RE: LDAP Client Update: consideration of alternative proposals

Based on an evaluation of the discussion relating to this thread,
WG Consensus has been established that we should stay with our
presently chartered course of action. This is reflected as item 4b)
below. To be more explicit, there is not sufficient support in the
WG to proceed according to the proposal made by Kurt to evaluate
both the existing WG deliverable and his individual submission
as alternatives prior to WG Last Call for LCUP.

We will post the LCUP WG Last Call announcement on Monday, June 16, 2003.
This WG Last Call announcement will only reference the WG Deliverable.

There are *no* restrictions on referencing parts of Kurt's individual
submission during the WG Last Call (or any other document) as long as
those references are intended to provide examples of clarifying text,
rationale for particular arguments, etc., in support of improving the
quality of the existing WG LCUP Deliverable.

Discussion about and suggestions/proposals to delay or retract
the WG Last Call in favor of initiating a technical comparative
analysis of the two drafts are will be out of scope after the
WG Last Call posting has been made.

The LCUP WG Last Call posting will be made late in the day US ET
on Monday, June 16, 2003. Most likely sometime that evening.

Chris Apple - Principal Architect

DSI Consulting, Inc.

mailto:[email protected]

http://www.dsi-consulting.com

-----Original Message-----
From: Chris Apple [mailto:[email protected]] 
Sent: Tuesday, May 27, 2003 3:05 PM
To: [email protected]; 'Kurt D. Zeilenga'; [email protected]
Cc: 'John Strassner'
Subject: RE: LDAP Client Update: consideration of alternative proposals


As WG Co-Chair, I want to be clear with WG Members about
the status of Kurt's request:

1) The WG needs to establish a consensus of support for
   proceeding as Kurt suggests in order for John and I
   to endorse it and make any requests for changes to
   milestone dates or other charter changes to our ADs.

2) It is an open topic for discussion. Specifically, John
   and I need to see comments (preferably with rationale)
   about the value (or lack thereof) of proceeding as
   Kurt suggests. Do not wait for further communication
   from either John, Kurt, or I to start this discussion.
   John and I don't want to have to resort to interpreting
   silence on this issue in one way or another.

   Make your opinions known NOW! This applies to you even
   if you are an author of one of the drafts covered by
   Kurt's request.

3) The milestone date for the WG Last Call for the LCUP
   deliverable is still May 2003 and requires approval
   of our ADs to slip intentionally.

4) John and I will await confirmation/clarification of our
   understanding of Kurt's request from Kurt before making
   the request to our ADs to slip the milestone date to give
   us enough time to consider whether the WG wishes to:

	a) proceed as Kurt suggests
	b) stay with our presently chartered course of action,
	   albeit with some slippage
	c) take another path completely different from those

Chris Apple - Principal Architect

DSI Consulting, Inc.

mailto:[email protected]

http://www.dsi-consulting.com

-----Original Message-----
From: [email protected] [mailto:[email protected]] On
Behalf Of Chris Apple
Sent: Tuesday, May 27, 2003 8:25 AM
To: 'Kurt D. Zeilenga'; [email protected]
Cc: 'John Strassner'
Subject: RE: LDAP Client Update: consideration of alternative proposals



WG Members should review the request Kurt has made.

John and I will respond to the list on the procedure
we'll use in considering Kurt's request, and if appropriate,
acting on it.

Kurt,

There are a few major points I'd like to be sure I'm 
summarizing correctly before John and I respond on the
procedural issue. You are requesting the following:

1) that the WG formally consider your individual
   contribution as an alternative to the existing
   WG deliverable for LDAPv3 Client Update Protocol.

2) that the WG evaluate both documents based on
   technical merit.

3) that the WG emerge from that evaluation process
   with a single document that will be processed
   through a WG Last Call and submitted to the Ads
   as the WG deliverable for LDAPv3 Client Update
   Protocol.

4) that the WG Last Call milestone for LCUP be
   rescheduled further out in time to accommodate
   the above.

Did I miss any key points in your request?

Do any of them need clarification?

Chris Apple - Principal Architect

DSI Consulting, Inc.

mailto:[email protected]

http://www.dsi-consulting.com

-----Original Message-----
From: Kurt D. Zeilenga [mailto:[email protected]] 
Sent: Monday, May 26, 2003 11:11 AM
To: [email protected]
Cc: Chris Apple; John Strassner
Subject: LDAP Client Update: consideration of alternative proposals


The LDUP WG is chartered to deliver:
  o LDAPv3 Client Update
        A protocol that enables an LDAP client to
        synchronize with the content of a directory
        information tree (DIT) stored by an LDAP server
        and to be notified about the changes to that
        content.

Over the last few years, the WG has engineering a technical
solution for this deliverable.  This solution is specified
in the I-D draft-ietf-ldup-lcup.  Over the last 9 months or
so, Jong and I, acting on an individual basis, engineered
a technical solution for this deliverable.  This solution is
specified in the I-D draft-zeilenga-ldup-sync. 

Each of these technical solutions are intended to fulfill
this deliverable.  I also believe both sets of authors
believe that their approach best fulfills this deliverable.
It is also likely many members of this WG have formed opinions
as to which technical solution best fulfills this deliverable.
However, it is unclear to me whether both I-D, in particular
the most recent revisions of each, have been thoroughly
considered by the WG.

WG I-Ds are implicitly viewed as being under WG consideration
and it hoped that significant number of WG members review the
I-D as it evolves.  Individual I-Ds are not necessarily viewed
as being under WG consideration unless submitted to the WG for
consideration by their authors.  They generally are reviewed by
few WG members until consideration is specifically requested.

I now submit the draft-zeilenga-ldup-sync to the LDUP WG
for consideration as a technical solution to its "LDAP Client
Update" deliverable.  I believe the latest revision,
draft-zeilenga-ldup-sync-02.txt, is suitable for progression.

I ask the WG to view draft-ietf-ldup-lcup and draft-zeilenga-ldup-sync
as technical alternatives and give thorough consideration to both.
It is up to the WG to decide which solution is technically
superior.  As it is the function of the WG Chairs to manage the
group process, I defer procedural questions and issues to Chris
and John.

As the differences between the approaches is fundamental in
their design, it will be difficult to compare them without some
basis to which can be measured against.  It may be appropriate
for the WG to examine what kinds of applications it intends its
deliverable to be applicable to, what the requirements of these
applications are, and how each of the technical alternatives
measures up to these requirements.  The WG should also consider
broader issues, such as chattiness and security considerations.
The WG should consider the appropriateness of the design and
other constraints each places upon implementations.

In regards to the WG milestone:

   May 03    LDAPv3 Client Update Protocol I-D goes
             to WG Last Call as Proposed Standard 

I would like the WG to defer this WG Last Call until it has
thoroughly consider both technical alternatives and reached a
consensus as to which alternative it would like to pursue.
Then that alternative should be prepared of WG Last Call as
the WG's "LDAPv3 Client Update Protocol I-D".  I believe it
necessary to defer the WG Last Call as the WG first needs to
thoroughly consider both alternatives.

I'd like to say a key design difference which is a major factor
in I considering draft-zeilenga-ldup-sync technically superior
to draft-ietf-ldup-lcup.  In attempting to implement
draft-ietf-ldup-lcup, we found that requires server implementations
to maintain complete history information in order to provide
eventually convergent incremental refreshes.  We found that
where the server only maintains simple state indicators such as
timestamps, it cannot generally provide eventually convergent
incremental refreshes.  If the server maintains partial histories,
the server will be limited in cases where it can provide
eventually convergent incremental refreshes.  In October 2002,
the WG consensus was declared on an alternative approach (but
later recanted).  We implemented this approach and found that it
allowed all of the above implementation variants to provide
eventually convergent incremental refreshes.  This was document
in documented in early revisions of draft-zeilenga-ldup-sync.
As a result of WG discussions about this approach, it was noted
that this approach didn't allow servers to take advantage of
histories they maintained.  In our latest revision, we adopted
a hybrid approach which allows servers to take advantage of
histories they maintained.  Hence, I believe draft-zeilenga-ldup-sync
is technical superior in that it does not place significant
implementation constraints in order to support eventually
convergent incremental refreshes while allowing implementations
take advantage of histories they maintain.  There are, of course,
many other factors in my consideration and I am quite willing to
elaborate on these in subsequent discussions.  Before doing so,
I will await direction from the chairs on how to proceed with
the consideration of the alternatives.

Comments?

Regards, Kurt