[PCN] Request for Pre-Congestion Notification BOF

Hello Lars and Magnus,

This message constitutes a formal request for Pre-Congestion
Notification BOF at the November IETF meeting in San Diego.  

The BOF description and its proposed agenda are attached at the end of
this message.

If this BOF is approved,  we would like to request a two-hour slot that
avoids scheduling conflicts with the following working groups:  tsv,
nsis, sip, ieprep, ecrit, pwe3, dccp.

We also ask that you CC agenda@ietf.org with your decision.

Of course we welcome any feedback you might have.

Best Regards,
Anna Charny

PCN BOF Description

The Pre-Congestion Notification (PCN)  BOF will address the problem of
how to provide scalable and resilient admission control and strong QoS
assurance while using packet marking techniques. Current attempts to
deliver QoS using only packet marking (e.g. DiffServ) are limited in the
level of QoS assurance that can be provided without substantial
over-provisioning. To improve the QoS assurance, PCN will add flow
admission control and flow pre-emption. In normal circumstances
admission control should protect the QoS of previously admitted flows.
In times of heavy congestion (for example caused by route changes due to
link or router failure) pre-emption of some flows should preserve the
QoS of remaining flows.

The overall approach will be based on a the concept of a PCN-Region,
within which the functionality is separated between the PCN-Interior
Node (PIN) and the PCN-End Node (PEN). The initial scope of the BOF will
be the case of a single DiffServ region, which maps to a PCN-Region.
PINs mark packet headers when their traffic is above a certain level, as
an early warning of incipient congestion ("pre-congestion"); this builds
on concepts from RFC 3168 "The Addition of Explicit Congestion
Notification to IP".  PENs monitor the markings and that information is
used to make flow admission control and pre-emption decisions. The
decisions could be made by the PENs or by a centralized system (which is
informed of the PCN information). 

The BOF will address the need and the motivation for PCN work in the
context of IETF, provide a brief overview of prior PCN efforts and
related work,  and review open issues.  The BOF will also discuss the
scope of work and solicit feedback on the proposed charter.  Ultimately,
the goal of the BOF is to solicit community feedback on whether the
problem is clear and needs to be addressed, and consequently whether the
creation of a new PCN WG within the scope of the proposed charter is
warranted.

The draft charter is available from
http://standards.nortel.com/pcn/PCN_draft_charter_v00.txt
<http://standards.nortel.com/pcn/PCN_draft_charter_v00.txt> .  The
problem statement and motivation for the PCN work is discussed in more
detail in draft-chan-pcn-problem-statement-00, which has been submitted
to IETF and is also available at
http://standards.nortel.com/pcn/draft-chan-pcn-problem-statement-00.txt
<http://standards.nortel.com/pcn/draft-chan-pcn-problem-statement-00.txt
> .

Proposed BOF agenda  

1.  Agenda bashing  (5 min)
2.  Motivation and Problem Statement presentation  (15 min)
3.  Discussion of motivation and problem statement (30 min)
4.  Overview of prior PCN efforts, related work and open issues (15 min)
5.  Overview of the proposed charter (10 min)
6.  Discussion/bashing of the proposed charter (20 min) 
7.  General discussion and poll on the WG creation (25 min)