Re: [v6ops] Stateful SLAAC (draft-ietf-v6ops-unique-ipv6-prefix-per-host)

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

On 10/11/2017 07:19, Templin, Fred L wrote:
>>> I don't see how this is a protocol change. Sending RAs unicast is
>>> already allowed by RFC 4861, so this is just an operational practice.
>>
>> That's incorrect. We are talking about sending multicasted internetlayer
>> packets to a unicast link-layer address. There's nothing in RFC4861 that
>> suggests you should do that. RFC6085 says "you shouldn't drop packets if
>> they are internet-layer multicast but link-layer unicast". But
>> certainly, unless a protocol spec says otherwise, the normal mapping
>> applies.
> 
> On this point, I agree with Fernando. RFC4861 says that RAs can be unicast but
> that means unicast at both L2 and L3 (i.e., and not multicasted at L3). 

Who says that? As Fernando reminded us, RFC6085 says otherwise.

> RFC5214
> is an example of where both L2/L3 unicast are used in RAs in the spirit of RFC4861 .
> 
> Is there some reason why the requirements of this draft cannot be satisfied
> by L3 unicast?

Hosts listen for L3 multicast RAs.

   Brian