Compression Encapsulation over IP BOF (COMPEN)
Reported by Rodney Thayer/Sable Technology
Summary
Twenty-three people attended the COMPEN BOF in Seattle. It was
generally agreed that there are situations where people have a need for
encapsulation, such as compression. It was the rough consensus of the
group that if a working group is formed, it should address the general
issue of encapsulation over IP. There was some discussion of whether or
not encapsulation over IP is a problem that is already being solved by
PPP, and whether PPP provides solutions to encapsulation problems. It
was established that there is enough interest to form a working group on
Generic Encapsulation Over IP, and the COMPEN mailing list will be used
to work together to modify the existing draft charter to reflect the
proposed working group's goals.
Presentations and Discussion
One compression encapsulation scheme was presented by Matt Lukens (see
slides following the minutes: Figures 1 and 2) and discussed by the
group. The group also discussed more general requirements for
encapsulation. Bob Enger (a user, in this context) brought up several
requirements and provided some additional pictures (see slides: Figure
3). Several common points were identified:
o Encapsulation of compressed data over IP is the right place to do
this---it is essentially a routing issue.
o Other groups have addressed the encapsulation problem in several
different circumstances, that is, encapsulation is something that
needs standardization. cisco has authored an informational
description of their Generic Router Encapsulation protocol; there
is a scheme for encapsulating IPX; and others are wrestling with
this issue.
o There is an interest in encapsulators being interoperable.
Charter for Proposed Working Group
The chairs of the proposed COMPEN Working Group will be Rodney Thayer
and Matt Lukens. The group will be chartered in the Internet Area.
Mailing lists already exist for the group. The general discussion list
is compen@world.std.com. To subscribe to the list, send a request to
compen-request@world.std.com. The archive of the list will be located
on ftp.std.com:/pub/compen-archive.
The following group description was written before the BOF was held:
The Compressed Encapsulation over IP Working Group (COMPEN) is
chartered to develop a protocol to be used to transmit
compressed data over IP. The current state of compression
technology has allowed the development of devices which provide
the capability to compress IP data. This working group is
intended to produce a document which describes a standard
envelopment protocol that can be used to allow a pair of
devices to exchanged compressed IP packets. It is the intent
of the working group to provide a standard protocol that will
allow different implementations of compression over IP (of
which several are now in existence) to interoperate. There
also is the need for the capability to support more than one
compression algorithm, and to support other encapsulation
schemes, such as encryption, when used in combination with
compression.
The group wants to provide a standard protocol for use in
compressing IP data to solve the problem of allowing
interoperability among devices that support compression. The
intent is to solve this interoperability problem by
establishing a common protocol. Currently, in order to
transmit compressed IP over the Internet, the same vendor's
equipment must be used on both ends.
The development of a standard encapsulation protocol is
important to the Internet community because the current state
of the technology allows individual implementations to exist
that do not interoperate with each other, and yet these
implementations are present side-by-side in the Internet. For
example, several parties are using Internet protocol type 99 to
represent compressed data using different encapsulation
schemes.
The development of a protocol for compression over IP is not
inconsistent with other uses of compression, such as within
modem standards or link-level protocols such as PPP. This is
because there are situations where users wish to interconnect
two nodes through an internetwork and they do not have control
of all intervening links, and therefore they have to transmit
IP across the internetwork to connect the two nodes.
The following goals and milestones were identified before the BOF
session:
March 94 Meet as a BOF and draft a charter for consideration as an
IETF working group. Submit the charter to the area
directors.
June 94 Release a document as an Internet-Draft
July 94 Present the Internet-Draft at the IETF meeting. Revise and
edit the document as needed.
Aug 94 Re-release the Internet-Draft.
Nov 94 Submit the Internet-Draft to the IESG for publication as an
RFC.
Compression Encapsulation Requirements
An outline of compression encapsulation requirements follows the minutes
(Slide 4).
Proposed Working Group Requirements
It was the rough consensus of the attendees that the group requirements
be modified to the following outline:
o General tunneling, not just compression
o Specifically address:
- Compression
- Encryption
- No data alteration, just protocol, such as CLNP, Mobile IP,
Appletalk, etc.
- Dynamic negotiation
- Fragmentation and expansion
- Tunnel re-establishment
o Address whether this is ``different'' from PPP over TCP (or
something else)
o Address whether this is different from GRE
Attendees
Larry Blunk ljb@merit.edu
Caralyn Brown cbrown@wellfleet.com
David Conrad davidc@iij.ad.jp
Ian Duncan id@cc.mcgill.ca
Robert Enger enger@seka.reston.ans.net
Shoji Fukutomi fuku@furukawa.co.jp
John Houlker j.houlker@waikato.ac.nz
Jim Hughes hughes@network.com
Jan-Olof Jemnemo Jan-Olof.Jemnemo@intg.telia.se
Akira Kato kato@wide.ad.jp
David Kaufman dek@magna.telco.com
Sun-Kwan Kimn sunkimn@cup.hp.com
Ted Kuo tik@vnet.ibm.com
Joshua Littlefield josh@cayman.com
Matt Lukens mlukens@world.std.com
Gary Malkin gmalkin@xylogics.com
Gerry Meyer gerry@spider.co.uk
William Miskovetz misko@cisco.com
Brad Parker brad@fcr.com
Doug Schremp dhs@magna.telco.com
Oscar Strohacker stroh@vnet.ibm.com
Rodney Thayer rodney@world.std.com
Walter Wimer ww0n+@andrew.cmu.edu