Subject: [PCN] draft meeting minutes for pcn

From: [email-masked] (Scott O. Bradner)
Date: Mon, 6 Apr 2009 09:17:20 -0400 (EDT)

comments to list asap

thanks

Scott

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PCN Meeting Notes
Friday morning Mar 27/09
Scott Bradner chairing

minutes by Tom Taylor and Kwok Ho Chan

Architecture Status -- Phillip Eardley
==============================
draft-ietf-pcn-architecture

Phillip Eardley: He is currently clearing IESG DISCUSS comments --
primarily editorial, clarifications

Lars Eggart (as AD): three new ADs have to state their opinions.
Outgoing AD comments no longer count -- incoming ADs will review and
decide whether they hold that position. Because the changes have been
substantial, new ADs will be encouraged to review from the start.
Suggests Phillip talk to broadest commenter.

Tom Taylor: pcn should have a common "elevator pitch" for PCN at the
start of every WG draft (Abstract and Introduction). Kwok Ho Chan noted
that there is material in the Problem Statement draft that was used to
start the WG can that be reused for this purpose. Tom has action to
draft.

Marking Behaviour -- Phillip Eardley
============================
draft-ietf-pcn-marking-behaviour

Phillip Eardley: Would like to go to WGLC. SATOH Daisuke has called for
delay.

SATOH Daisuke: Without a third code point, termination and admission are
inaccurate. He said that he had ideas for improving accuracy, but needs
more time (measured in weeks) to simulate them. 

Phillip Eardley: have to make a decision at some point. We already cut
off another proposal that had asked for more time and had not come
through within the period given.

Lars Eggart: does Daisuke believe current approaches don't work at all
or work less accurately than can be achieved? 

SATOH Daisuke: Only have Single Marking according to the intended
standard.
 
Phillip Eardley: operator has deployment choices. Daisuke is
concentrating on a single case. 

Bob Briscoe: Daisuke's proposed marking behaviour would preclude
migration to three-code-point marking.

Giorgios Karagiannis: as target of last year's closure, he accepts that
it is time to put something on the ground and experiment with
improvements after we have experience.

Lars Eggart: we don't intend to have multiple marking behaviours.

Chair: reasonable to go to WGLC. This discussion can be part of the WGLC
discussion.

Baseline Encoding -- Phillip Eardley
============================
draft-ietf-pcn-baseline-encoding

Tom Taylor:  he put some of the encoding discussion into the behavior
draft

Phillip Eardley:  Talking about "What's Next" slide. Code point
transitions are specified in each encoding document. Tom noted that also
summarized in the edge behaviour "core assumptions" sections.

Re ECN tunneling draft: thoroughly rewritten -- more report later.

Last call discussion: 

Gorry Fairhurst noted that lots of editorial nits, but OK technically.

Chair: will take to WGLC after nits addressed.

Edge behaviour drafts -- Tom Taylor (for Anna)
============================

Tom Taylor: Will be submitted as WG documents after next revision (in
line with discussion results).

Bob Briscoe: these drafts are informational drafts and they are
informational on some experimental ideas

Ken Carlberg: he have a draft on Emergency and that scares people, hence
Ken's draft will pull out the notion of "Emergency".

Tom Taylor: the decision point should be in the loop for flow
terminations

Tom has action to write up draft on "How to write an edge behaviour
draft", incorporating by reference "Per domain behaviour" draft
(reference to be obtained). CL and SM drafts should be updated to
include per domain behaviour.

Bob Briscoe: template draft should reference Kathie Nichols's PHB
template RFC 3086

Three state encoding -- Phillip Eardley
===============================

Phillip Eardley: Time to look at experimental extensions. 

Toby Moncaster: "Basic 3 state" and "Extended 3 state" encodings from
the baseline draft presentation. "Extended" is used to carry ECN marking
across the PCN domain.

Bob Briscoe: "3 in 1" based on premise that tunnel behaviour is
suitable. No tunnels, or tunnels end in your network or at its edge.

PSDM has dual mode. Overwrites ECN.

Proposal is that all three become WG documents.

Giorgios Karagiannis: supports. Wants to work on HOSE model after basic
set done, hence would need the "Affected Marking" codepoint. But this
would be after the initial set done.

Gorry: are the two DSCPs related or just arbitrary? Giorgios -- should
be related, same PHB. Kwok Ho suggests AF. 

Lars Eggart: logically related obviously. But (general agreement) no
need for a numerical relationship.
Second DSCP would have to be reallocated, but evidence of successful
experiment would be strong argument in favor.

Bob Briscoe: are we aiming to have a few experimental proposals and then
narrow down to one result, or just leave it to local use?

Lars Eggart: if we go to multi-domain, experimental is going to be
interesting because of potential clashes with other experiments.

support in room that PSDM, Moncaster 3-state, and 3 in 1  become WG
drafts, aiming at Experimental.

Jabber comment (Steven Blake): Wiki available for public notification of
PCN experiments. Further comment on use of Pool 1 vs. Pool 2, which will
not be allocated until Pool 1 is exhausted.
[Follow-up note to list]

Lars Eggart: PCN should also start a wiki page on IETF site indicating
which DSCPs are used for PCN experiments.

Tunneling of ECN -- Bob Briscoe
===============================
draft-ietf-tsvwg-ecn-tunnel-02.txt

Bob Briscoe: Layered encapsulation. Intended to be Standards Track. 

Summary on charts.

Proposal: 
At ingress, bring ECN tunneling in line with IPSec.
At egress: use two wasted combinations of inner and outer codepoints.
Absolutely no backward compatibility issues.

Gorry: OK on merits. But assumes ECT(1) is more severe than ECT(0). Is
this the intention? Seems consistent with others' suggestions.

Kwok Ho: ECT(1) usage new? Gorry: ECN nonce doesn't have this concept,
but original ECN did.

Chair: basically this is a TSVWG discussion.

Bob Briscoe: Discussion on TSVWG list: don't necessarily need to drop
illegal combinations.

Gorry: actually now distinguishing (0) and (1). Have to think through
the implications.

Kwok Ho Chan will review the draft.

PCN Encoding Comparison - Kwok Ho Chan
======================================

Kwok Ho Chan: Charter work item.
Tracks reasoning leading to current positions
Question is whether this draft should be continued or closed?

Chair suggestion: output as Informational now, can update later. Make it
a Working Group draft.

No further points. Finished at 10:45.