Re: [6lowpan] -nd-15: Joining the all-nodes multicast address

[Erik Nordmark <[e-mail]>]

On 2/25/11 5:28 AM, Colin O'Flynn wrote:
> Hi Anders,
>
> RFC4861 uses the same wording, where it means you just listen on the
> all-nodes multicast address. There is no explicit join method.
>
> I'm not sure in which RFC it describes joining the multicast group. I would
> guess RFC4291 as that describes multicast addressing, but there might be
> somewhere better.

It is in RFC 2710 on MLD; it describes that "join" implies.

MLD has an explicit exception for all-nodes as in
    The link-scope all-nodes address (FF02::1) is handled as a special
    case.  The node starts in Idle Listener state for that address on
    every interface, never transitions to another state, and never sends
    a Report or Done for that address.

For other multicast addresses, including link-locals, the expectation is 
that the host would join using MLD.

Note that 6lowpan-nd doesn't require hosts to join the solicited node 
multicast address; that would have required sending MLD reports to 
comply with RFC 2710.

    Erik