6. Appendix A. Changes from RFC 2486(-> 4282^prop)

   This document contains the following updates with respect to the
   original NAI definition in RFC 2486(-> 4282prop) [RFC2486]:

   o  International character set support has been added for both
      usernames and realms.  Note that this implies character codes 128
      - 255 may be used in the username portion, which may be
      unacceptable to nodes that only support RFC 2486(-> 4282prop).  Many devices
      already allow this behaviour, however.

   o  Username privacy support has been added.  Note that NAIs without a
      username (for privacy) may not be acceptable to RFC 2486(-> 4282prop)-compliant
      nodes.  Many devices already allow this behaviour, however.

   o  A recommendation to support NAI length of at least 253 octets has
      been added, and compatibility considerations among NAI lengths in
      this specification and various AAA protocols are discussed.  Note
      that long NAIs may not be acceptable to RFC 2486(-> 4282prop)-compliant nodes.

   o  The mediating network syntax and its implications have been fully
      described and not given only as an example.  Note that this syntax
      is not intended to be a full solution to network discovery and
      selection needs as defined in [netsel-problem].  Rather, it is
      intended as a clarification of RFC 2486(-> 4282prop).

      However, as discussed in Section 2.7, this specification requires
      that this syntax be applied only when there is explicit knowledge
      that the peer system supports such syntax.

   o  The realm BNF entry definition has been changed to avoid an error
      (infinite recursion) in the original specification.

   o  Several clarifications and improvements have been incorporated
      into the ABNF specification for NAIs.