Subject: IETF46 - GSMP WG draft minutes

From: "Kenneth Sundell" <[email-masked]>
Date: Thu, 25 Nov 1999 08:02:45 +0100

IETF 46 - GSMP Working Group
The meeting was chaired by, and minutes are provided by, Avri Doria and
Kenneth Sundell.

The meeting was divided into 2 sessions.  The first session was devoted
primary to a review of ongoing work, while the second session was
devoted to discussions of proposals submitted for improving GSMP.

GSMPv3 Document Status

Tom Worster started the meeting by giving a status of the GSMPv3
specification. Now that most of the charter related items have been
submitted, it is time to start preparing the document for last call.
The plan is to fix all of the items listed in his presentation and to do
working group last call on the email list before IETF47.

One of the pending issues had to do with security mechanisms in GSMP.
The working group accepted the proposal that IPsec would be required for
IP implementations.  Since GSMP can also be implemented directly over
Ethernet or ATM, IPsec would not be required in those cases. Tom will
produce language on security that covers IP, ATM etc.

There was also a discussion of specific MPLS labels.  Though the label
definition have been opened up to accept MPLS labels we still need
volunteer to define these labels.

Application for IANA number support

Avri presented a list of numbers for which IANA application would be
made.  The group accepted the proposal with one modification.  Group
consensus was against including service configuration IDs among the
externally defined numbers.

GSMP MIB

Hans Sjostrand presented the GSMP MIB.  This is as yet a bare bones MIB
which need to include information to support partitioning and partition
specific information.  A MIB design team was formed consisting of: Hans,
Balaji Srinivasan and Joachim Buerkle.  As the group received
information that the MSF was interested in working on the MIB as well,
the liaison was asked to find out the extent and availability of people
from the MSF to participate in the MIB work.

MPLS Reservations

There were two presentations on methods for supporting MPLS
reservations.  Joachim Buerkle presented his proposal for the addition
of usage bits for this purpose, while Tom Worster proposed the addition
of a reservation command.  Joachim agreed to work put aside his proposal
in favor of the new command.  Tom and Joachim agreed to work together on
language that would be added to the GSMPv3 specification.  It was noted
during the discussion that the reservations needed to be per partition.
Also, some issues where discussed about how to handle the reservations
when the CAC was on the controller.

A follow-up MSF Liaison was presented.  This was a response to the
questions the GSMP WG had sent after IETF45.

Second Meeting:

A minimal ATM switch resource model

Constantin Adams presented an ATM Switch minimal resource model. The
purpose was to include a minimal resource model together with a set of
messages for exposing, configuring and controlling these resources into
GSMPv3.
How to move this work forward? The authors were in favor for granting
the document as a working group document. The minimal resource model as
such was accepted, but the document consists of a number of other models
as well, for example switch fabric, port and connection models. The
working group chairs suggested that the document should be reworked,
i.e. to leave out details of other models and submit it as working group
document. The group agreed. A number of comments were raised regarding
limitations on e.g. buffering policy. Discussions will continue on the
GSMP list. It was also decided that the co-chairs should pre-review the
rewritten draft before granting it as working group document.

A QoS extension to the minimal resource set

Mahesan Nandikesan presented a QoS extension to the previously discussed
minimal resource model. He presented a set of messages in order to
guarantee QoS for a schedulable region, which is an abstraction that
captures the capacity of a multiplexer. The messages are intended to be
used in conjunction with the messages provided with the minimal resource
model discussed in the previous presentation. Questions were raised
whether these QoS extensions should be included into the minimal
resource model proposal. This was not the goal of the authors. There was
a feeling from the group that the proposal included extensions to an
extension, especially regarding MType negotiation during the
initialization phase. It was felt that a model should be regarded as a
complete package, so the question was if this should be folded into the
Mtype=1. There were no objections, so in practice the work was in direct
approved as a working group document.

An ATM switch service model for GSMP

Mahesan Nandikesan presented an ATM switch service model for GSMP. The
proposed services are inherited from work done in the IEEE PIN working
group. Currently IEEE PIN is using an API; this document proposes the
use of GSMP instead.  The authors are proposing to include the traffic
and QoS parameters in a special add branch message, with input and
output labels equal to zero. This change would introduce a change in
behavior for this add branch message since the combination would imply;
no connection. This statement raised objections in the crowd, since
VPI=0, VCI=0 is a valid connection in a switch. The working group agreed
that this document doesn’t yet fit the service model straight jacket.
The document is not approved in current shape as a working group
document. Discussions will happen on the GSMP list.

Adding redundancy to GSMP

Kenneth Sundell proposed to add a new event message and changes to the
switch configuration request/response message in order to enable
controller redundancy in GSMP. The event message was introduced in order
to notify the controllers that other controllers for a certain partition
exists. The purpose of the new changes to the configuration message was
to also give the controllers networking addresses to all controllers for
a certain partition. He also proposed a partition state machine for this
purpose with specific demands for a switch partition MIB.

The group accepted the basic idea. However, the responsibility for
controllers to find each other was not regarded to be the role of GSMP.
The state machine has to be described more in detail.  A new version of
the draft is expected in order to reflect the suggestions that raised
during the meeting. The draft will, when approved, be folded into the
GSMPv3 specification.

GSMP Enhancements

Balaji Srinivasan presented a number of proposed enhancements to the
GSMP. The proposal consists of quite a number of changes with emphasis
on simplification of message parsing and improving the support for
multiple partitions. During the presentation he also proposed changes
for to better support multi-point to point messages and also a number of
different issues that were not included in the draft but posted on the
mailing list prior the presentation.

There was a desire of the group that the adjacency message should be
excluded from the re-hash of all messages since it currently can be
accommodated in one single ATM cell.
There was discussion of the proposal of changing the message format to
aid in forwarding.  There was no consensus reached on this issue.

There was also a proposal that the GSMPPv3 specification be divided into
several documents.  One would contain the main part of the
specification, while the others would each document a message
encapsulation.

There were a lot of agreements in principle but not in fact. There were
issues that need to be discussed on the list. A three-week list
discussion time period is set. The authors of the drafts are expected to
start these negotiations.

Extended move branch concept for GSMP

Joachim Buerkle made a brief presentation on issues with the move
command.  The consensus of the group as to accept the problem as work
item and to continue discussion on the list.

--

Regards,
Kenneth and Avri