Re: draft-bourbaki-6man-classless-ipv6-00

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> 
> "Interface Identifiers should be 64 bit long except
> when the addresses are manually configured,
> 
> In order to publish that text we need to agree on what it means. Can you explain the semantics of the the interface identifier of a manually configured IPv6 address? What are they used for?
> 
> Note: the semantics are *not* the same as the prefix length of an IPv4 address. The prefix length of an IPv4 address implies that that subnet is reachable on, but the IID implies nothing about reachability.

I'm not sure I understand your point.

RFC4291:

   IPv6 nodes may have considerable or little knowledge of the internal
   structure of the IPv6 address, depending on the role the node plays
   (for instance, host versus router).  At a minimum, a node may
   consider that unicast addresses (including its own) have no internal
   structure:

   |                           128 bits                              |
   +-----------------------------------------------------------------+
   |                          node address                           |
   +-----------------------------------------------------------------+

   A slightly sophisticated host (but still rather simple) may
   additionally be aware of subnet prefix(es) for the link(s) it is
   attached to, where different addresses may have different values for
   n:

   |          n bits               |           128-n bits            |
   +-------------------------------+---------------------------------+
   |       subnet prefix           |           interface ID          |
   +-------------------------------+---------------------------------+


Ole