RFC 2072 (rfc2072) - Page 3 of 48

Router Renumbering Guide

RFC 2072                Router Renumbering Guide            January 1997


      3.  Before the actual renumbering, it can be useful to evolve
          the current environment and current numbering to a more
          "renumbering-friendly" system.  Section 5 discusses ways to
          introduce renumbering friendliness into current systems.

      4.  Be aware of potential pitfalls.  These are discussed in
          Section 6.

      5.  Identify potential requirements for tools, discussed in
          Section 7.

      6.  Evaluate the specific router mechanisms that will be affected
          by renumbering.  See Sections 8 through 13.

      7.  Set up a specific transition plan framework.  Guidelines
          for such planning are in Section 15.

   When trying to understand the interactions of renumbering on routers,
   remember there different aspects to the problem, depending on the
   scope of the renumbering involved.  Remember that even an
   enterprise-wide renumbering probably will not affect all IP addresses
   visible within the enterprise, since some addresses (e.g., Internet
   service providers, external business partners) are outside the
   address space under the control of the enterprise.

2. Disclaimer

   The main part of this document is intended to be vendor-independent.
   Not all features discussed, of course, have been implemented on all
   routers.    This document should not be used as a general comparison
   of the richness of features of  different implementations.
   References here are only to those features affected by renumbering.
   Some illustrative examples may be used that cite vendor-specific
   characteristics.  These examples do not necessarily reflect the
   current status of products.

3.  Motivations for Renumbering

   Reasons to renumber can be technological, organizational, or both.
   Technological reasons fall into several broad categories discussed
   below.  Just as there can be both technological and organizational
   motivations for renumbering [RFC 2071], there can be multiple
   technological reasons.

   There may not be a clear line between organizational and technical
   reasons for renumbering.  While networks have a charm and beauty all
   their own, the organizational reasons should be defined first in
   order to justify the budget for the technical renumbering.  There



Berkowitz                    Informational