Re: RFC4291bis

[Brian E Carpenter <[e-mail]>]

On 08/08/2018 12:07, Manfredi (US), Albert E wrote:
> -----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.]

Thanks, that works for me.

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

See my response to Michael's message.

    Brian