Subject: Re: [Roll] Closing on issue 54

From: "Pascal Thubert (pthubert)" <[email-masked]>
Date: Tue, 22 Jun 2010 17:30:24 +0200

Hi:

The consensus is:

1)      NOT MUST (SHOULD slightly ahead if you include my own vote)

2)      LL RPL nodes                   [that we need to request to IANA]

3)      NOT dumb flooding, trickle slightly favored and the description belongs elsewhere anyway.

Proposal:

Clearly, the group wishes to ask for a new multicast group for RPL. That will be included in rev 10.

Obviously also, non-storing mode do not need to support the stateful multicast as presented in the draft. The light consensus is that storing nodes SHOULD support it. Since the root needs to know and enforce a multicast operation, we’ll add a flag similar to the ‘A’ flag in the DIO base whereby routers that do not have the capability join as leaves.

Finally, we’ll make it clear that the alternate multicast method(s) are to be specified in a different spec.

If you oppose to this resolution please speak up now!

Pascal

From: [email-masked] [mailto:[email-masked]] On Behalf Of Pascal Thubert (pthubert)
Sent: Friday, June 18, 2010 2:24 PM
To: [email-masked]
Subject: [Roll] Closing on issue 54

Dear WG:

We’d like to close on issue 54 by draft 10. There are in fact 3 questions on the table. Can you please spend a few minutes to gives us your vote on each:

1)      It has been noted that In some small networks, the non-storing mode approach of flooding or many unicast would be acceptable as a multicast approach.  Please vote whether the support of DAO based multicast on storing nodes should be a:

a.       MAY 

b.      SHOULD 

c.       MUST

2)      LL multicast address used for RPL control.  At the moment, all mcast control goes to FF02::1, which might bother more nodes than need be. Please vote to use:

a.       - all nodes                           [RFC4291]

b.      - all routers                         [RFC4291]

c.       - LL MANET nodes           [RFC5498]

d.      - LL RPL nodes                   [that we need to request to IANA] 

3)      Non storing nodes. They cannot do the DAO based stateful multicast so we plan to allow the root to either do many unicast or flood. Unicast is straightforward but flooding might require some text WRT pruning and use of trickle. To avoid duplication, the art usually adds a sequence to each packet being flooded. If we have such a sequence we can use it alone or in conjunction with trickle to prune excess multicast. Please vote:

a.       Do not prune anything, just propagate downwards all the multicast packets from parents (simplest but greedy)

b.      a + Describe the sequence nb in the hop-by-hop spec to prune flooded duplicates

c.       b + Describe the trickled version of it

Votes appreciated J

Pascal