RE: RFC4291bis

["Manfredi (US), Albert E" <[e-mail]>]

-----Original Message-----
From: ipv6 <[e-mail]> On Behalf Of Brian E Carpenter

> NEW:
   Interface Identifiers for stateless address autoconfiguration
   are 64 bits long except if the first three bits
   of the address are 000, or when the addresses are manually
   configured, or by exceptions defined in standards track documents.
   The rationale for using 64 bit Interface Identifiers can be found in
   [RFC7421].  An example of a standards track exception is [RFC6164]
   that standardises 127 bit prefixes on inter-router point-to-point
   links. The relationship between prefix length and Interface Identifier
   length is discussed in [I-D.farmer-6man-exceptions-64].

      Note: In the case of manual configuration, the Prefix and
      Interface Identifier can be any length as long as they add up to
      128. In all cases, routing and forwarding processes must be
      designed to process prefixes of any length up to /128 [BCP198].

But I think those exceptions are not SLAAC-related at all. So perhaps:

NEWNEW

   Interface Identifiers for stateless address autoconfiguration
   are 64 bits long. Otherwise, IIDs are normally 64 bits long, except
   if the first three bits of the address are 000, or when the addresses
   are manually configured, or by exceptions defined in standards track
   documents. ... [Rest same as before.]

I'm not sure if there's any reason to mention that these rules only apply to the 2000 prefix.

Bert