IGMP routing startup

Archived from groups: comp.dcom.lans.ethernet (More info?)

I'm trying to understand how an IGMP router gets started. It _seems_
to me that there's a state transition missing in RFC 2236 (or maybe
it's implied and I haven't figured that out yet).

Consider this network:

+---------+
| Server |
+---------+
|
--+---+-----------+---- N1
| |
+--------+ +----------+
| Host 1 | | Router 1 |
+--------+ +----------+
|
---+-----------+------ N2
|
+----------+
| Router 2 |
+----------+
| |
+--------+ +--------+
| Host 2 | | Host 3 |
+--------+ +--------+

With Host 1 a member of a multicast group served by Server, Router 2
powered off, and Host 2 and Host 3 wanting to be part of the multicast
group but unable to reach Router 1 or Server. Router 1 has a lower IP
address than Router 2 and will remain the Querier on N2 even after
Router 2 is fully initialized.

As I understand it, when Router 2 powers up, it'll send a General
Query on all it's interfaces. Router 1 should ignore that because
Router 2's IP address is higher. Host 2 and Host 3 should respond
with Reports (after suitable, random delays). Now Router 2 knows Host
2 and Host 3 are there and want to be members of the group but Router
1 hasn't seen the Reports so it doesn't route the multicast data to
Router 2 to forward.

Eventually, Router 1 times out and sends a General Query which Router
2 sees. If Router 2 sends a proxy Report for the group Host 2 and
Host 3 want to be in, things get goind OK after this but I don't see
anything in RFC 2236 that says such a proxy Report is sent. (I've
been through is many, many times and I'm kind of bleary eyed so maybe
I'm missing it.)

I can see a couple of ways to speed up convergence of this network but
neither seems to be prescribed by RFC 2236.

First, if Router 2 floods the first Report to all ports but the one it
was received on, Router 1 would see an Unsolicited Report and could
add that group to its routing table. (And the other one of Host 2 and
Host 3 would stop their timer and not send a Report at all.) Is that
flood part of "notify routing +"?

Second, if Router 1 sends a General Query of its own when the link to
N2 becomes active, Router 2 would be aware that there's another router
out there and that could lead to some magic that converged the
network.

I'm sure I've skipped over something. IGMP works, right? ;-) Any
pointers to my failing would be appreciated. Thanks.

Chris