draft-ietf-6man-prefixlen-p2p-01 clarification

[Michael Sinatra]

On 3/23/11 9:58 AM, Miya Kohno wrote:
> Hi Michael,
>
>> But if subnet-router anycast is turned of, should that matter?
>
> As for the actual behavior, that should not be a matter.
> It's for the sake of double check.
>
>> RFC 4291 only states that the zeroth host bits
>> *of a given prefixlen* not be used (i.e. the last 128-prefixlen bits
>> cannot be zero).
>
> Yes, but in the section 2.5.4, it says:
>   All Global Unicast addresses other than those that start with binary
>   000 have a 64-bit interface ID field
>
> So some stereotyped implementations could automatically think that the
> prefixlen should be 64 bit and so all zeros in the rightmost 64 bits
> should mean subnet-router anycast. I think it's not likely, but just to
> be safe.

Ah, that's what I thought you were trying to get at.

> Hope this clarifies.

It does--thank you!

michael