RFC 1688 (rfc1688) - Page 2 of 9

IPng Mobility Considerations

RFC 1688                     IPng Mobility                   August 1994


      6.2       Simple Fields ...................................    9
      6.3       Simple Tests ....................................    9
      6.4       Type, Length, Value .............................    9
   Acknowledgements .............................................    9
   Security Considerations ......................................    9
   Author's Address .............................................    9

1.  Introduction

   Current versions of the Internet Protocol make an implicit assumption
   that a node's point of attachment remains fixed.  Datagrams are sent
   to a node based on the location information contained in the node's
   IP address.

   If a node moves while keeping its IP address unchanged, its IP
   network number will not reflect its new point of attachment.  The
   routing protocols will not be able to route datagrams to it
   correctly.

   A number of considerations arise for routing these datagrams to a
   Mobile Node.

2.  Addressing

   Each Mobile Node must have at least one Home-Address which identifies
   it to other nodes.  This Home-Address must be globally unique.

2.1.  Ownership

   The presence of ownership information in the Home-Address would be
   beneficial.  A Mobile Node will be assigned a Home-Address by the
   organization that owns the machine, and will be able to use that
   Home-Address regardless of the current point of attachment.

   The ownership information must be organized in such a fashion to
   facilitate "inverse" lookup in the Domain Name Service, and other
   future services.

   Ownership information could be used by other nodes to ascertain the
   current topological location of the Mobile Node.

   Ownership information could also be used for generation of accounting
   records.








Simpson