The following text is copyright 1993 by
Network World, permission is hearby given for reproduction, as long as
attribution is given and this notice is included.
By: Scott Bradner
Back in August I wrote
about the not quite impending end of the Internet due to address exhaustion. At
the end of that column I said "Use of CIDR does not obviate the need to
choose a new IP, but by postponing the deadline for the choice, it will allow a
more measured decision process." Well, saying things like that can get a
body in trouble. As some of you may have read I've now been appointed
co-director of a new temporary area within the IETF that is charged with making
a recommendation on 'IP: next generation' (IPng), as it is now known.
On November 1st at the
IETF meeting in Houston Texas, Allison Mankin (the other co-director) and I
presented the procedure that we will follow in making this recommendation. It
seemed to be reasonable to take this opportunity to describe that procedure
here.
During the first phase
of the process there will be five concurrent activities.
a/ Ascertain available
time frame: A new IETF working group (Address Lifetime Expectations (ALE) ) has
been formed to make estimates of the remaining useful lifetime of the address
space used by the existing version of IP. The estimate will be made taking into
account the use of CIDR, the changing address assignment policies and the
availability of additional procedural documentation showing how to make more
efficient use of assigned space. This group will also develop an understanding
of the development and deployment time inherent in a switch to a new IP.
b/ Determine IPng
requirements and technology availability. A second working group is being
formed that will determine the set of features and functions that a new IP
should support. Since some of the desired features will require additional
research and development, realistic estimates will be made for the availability
timeframe for each of the features.
c/ Develop strategies to
deal with testing, transition and coexistence. A third working group will be
formed to develop an understanding of the operational issues involved in the
migration of the Internet to a new internet protocol. Particular emphasis will
be placed on planning a testing process. There may be bugs in the initial set
of standards and almost certainly there will be interoperability problems with
the initial implementations. It is very important that by the time the new IP
is deployed in a production network that it be as reliable as it can be. Since
it is reasonable to expect that additional features will be added to IPng as
time goes by (as features were added to the current IP), this group will be
charged to create generic plans rather than target the existing proposals.
d/ Insure the best
proposals. An extensive review process is being set up to ensure that the
proposals for IPng are as good as they can be. An IPng choice should not be
influenced by unclear or incomplete specifications. Each of the proposal documents
will be first reviewed for clarity and completeness with the reviewers giving
specific suggestions for improvement. Once the documents have passed muster in
this phase they will be reviewed for technical feasibility. Note that this
technical review is done within the context of the proposal, i.e., a reviewer
cannot request changes just because of a disagreement over the width of the
address, for example.
e/ White papers. In a
new process for the IETF, the IPng area is inviting the submission of white
papers from the wider networking community. The papers fall into two
categories: they can help define the requirements for an IPng or they can offer
solutions to the problems. These documents must follow a specific outline and
are reviewed following the same procedures outlined above. They are used as
resource material for the requirement and transition working groups and as an
information repository. Each of the IPng proposals will be described in a white
paper.
The IPng process is
managed by the area co-directors assisted by a directorate recruited from a
variety of sources. The directorate includes J. Allard (Microsoft), Steve
Bellovin (AT&T), Jim Bound (Digital), Ross Callon (Wellfleet), Brian
Carpenter (CERN), Dave Clark (MIT), John Curran (NEARnet), Steve Deering
(Xerox), Dino Farinacci (Cisco), Paul Francis (Bellcore), Eric Fleischmann
(Boeing), Daniel Karrenberg (RARE ), Mark Knopper (MERIT), Greg Minshall
(Novell), Paul Mockapetris (ISI), Rob Ullmann (Lotus) and Lixia Zhang (Xerox).
In addition, an expert review panel is being assembled and will be announced in
the near future.
The initial phase
described above is scheduled to be completed in April 1994. At that time the
results of the ALE and requirements working groups will be combined to determine
the final selection criteria. The proponents of each of the proposals will be
asked to produce a white paper detailing how their proposal will meet the
requirements and the associated timeframe. Public comment will be invited on
these documents.
The final IPng selection
with whatever specific suggestions may be warranted will be made by the area
co-directors and ratified by IESG after an extended public review process. The
selection is currently due to be presented at the IETF meeting in Toronto in July
1994.
Disclaimer of the month
is from me - The above opinions are mine alone. In no way should it be assumed
that anyone at Harvard shares them. (Though you are welcome to if they fit your
own predilections)
sob@harvard.edu
ps - the archive for the
IPng documents is on ndtl.harvard.edu in pub/ipng for anonymous ftp
pps - Just to insure
that there is no chance of any conflict of interest, I will donate my fee for
this column to charity.