Internet Draft                                              Bill Manning
April 1996                                                           ISI 
Expires in six months


			Why consider Renumbering Now
	             draft-manning-pier-consider-00.txt

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	This document is a fuller explanation of the intent and 
goals of the PIER working group of the IETF.

	The current charter states that PIER will work with other 
groups in identifying those locations in IP where the actual IP 
addresses are used. This will lead to the development of a series 
of educational materials for users of IP to recognize where IP 
addresses are used.  In addition, PIER will assist other IETF working 
groups in identifying processes and procedures, tools and techniques 
that can be used to facilitate renumbering.

	That raises the question of why even consider renumbering. 
The salient points have been raised in an IAB document[1] and on 
various mailing lists.  To summarize, in IPv6, renumbering is a basic 
design consideration, along with mobility and security. For those 
that embrace this new version of IP, renumbering considerations must 
be taken in to account in the network design and operations phases.  

	In IPv4, this was not part of the original design constraint, 
therefore most existing network infrastructure was designed without 
any hooks to which facilitate easier renumbering.  It is within PIERs 
charter to encourage those who design networks to consider adding 
renumbering elements to future designs and in redesigns, as network 
topologies are upgraded and changed. Consideration of renumbering in 
the design will make future operations much easier. It could even be 
argued that such features allow any network to be more nimble and react
to changes faster, leading to a competitive edge.

	The results in this approach are that as the designs change, 
the network infrastructure mutates to be able to support renumbering. 
This can be a slow mutation, allowing for advances in renumbering 
techniques to mature. The larger tasks are efforts to change user 
perception regarding the value of any particular IP address.  Others 
have taken up this challenge and have produced a number of documents 
that attempt to educate old and new IP users on this topic [2],[3].  
PIERS efforts in this area are to provide additional education and 
perhaps even one on one assistance in understanding the options 
surrounding IP address selection.  Regardless of the outcome, some 
social engineering will have been done, pointing out the logistics 
involved in the renumbering process.

	And what about those who will not be migrating to IPv6 and do 
not believe that IPv6 has anything viable to offer the Internet?  ALE 
predictions indicate that the global Internet will run out of IPv4 space 
eventually. One of the only ways to extend the lifetime of IPv4 is 
through aggressive renumbering. This has been argued forcefully in other 
mailing lists[4].  While the relative merits of this approach (staying 
with IPv4 and aggressively renumbering into provider blocks) are still 
being debated, the problem has similar characteristics to the IPv6 
migration issues mentioned above.  

	It is the intent of the PIER wg to facilitate the education 
of both old and new IP users as well as architects and protocol and 
application designers on the need to consider renumbering in network 
design and operations.

[1] - RFC1900
[2] - Address Ownership considered Fatal - Yakov Rekter, Tony Li, Connexions
[3] - R. Moskowitz - 
[4] - CIDR archives - 1995/1996

Security considerations of this memo

   None.

Authors Address

	Bill Manning
	USC/ISI
	4676 Admiralty Way
	Marina del Rey, CA. 90292
	01.310.822.1511
	bmanning@isi.edu