Internet Draft                                                T.Hain
   Document: draft-hain-1918bis-00.txt                    Cisco Systems
   Expires: October 2004                                     April 2004


             Expanded Address Allocation for Private Internets


Status of this Memo

   This document is an Internet-Draft and is in full conformance with
   all provisions of Section 10 of RFC2026 [1].

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups.  Note that
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Abstract

   This document updates RFC 1918 and identifies additional IPv4 address
   space for use in private networks.


Table of Contents

   Introduction......................................................2
   Private Address Space.............................................2
   IANA Considerations...............................................2
   Security Considerations...........................................2
   References........................................................2
   Author's Addresses................................................3








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Introduction

   A number of organizations have expanded their autonomous private
   networks to the point of exhausting the address space identified in
   RFC 1918, in addition to the publicly routed space that has been
   assigned to them. Given the policies for acquiring additional public
   space it is not reasonable for them to acquire such space for use in
   their private networks.

   While it is tempting to tell them to just switch to IPv6, that is not
   realistic from application availability, and transition timeframe
   standpoint. They need additional IPv4 space to continue to grow
   during the transition period. That space should be formally allocated
   rather than simply taken on the assumption it will not be publicly
   allocated before they complete a transition to IPv6.


Private Address Space

   The Internet Assigned Numbers Authority (IANA) has reserved the
   following blocks of the IPv4 address space for private internets:

   x.0.0.0 /8
   y.0.0.0 /8
   z.0.0.0 /8

IANA Considerations

   IANA should select additional IPv4 /8's for this purpose from those
   least likely to be allocated for public use. The prefix 1 /8 is a
   prime candidate as the author is aware of multiple networks that have
   historically used it for private use. Another candidate, 223 /8 was
   recently returned to IANA due to conflicts with RFC 3330.


Security Considerations

   While product marketing frequently confuses the use of private
   address space with security, there are no such claims being made or
   validated by this document.


References


   1  Bradner, S., "The Internet Standards Process -- Revision 3", BCP
      9, RFC 2026, October 1996.




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Author's Addresses

   Tony Hain
   Cisco Systems
   500 108th NE, Bellevue, Wa. 98004
   Email: alh-ietf@tndh.net











































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