Subject: Re: [magma] Doubt regarding Snooping and Proxy function of a switch.

From: Haixiang He <[email-masked]>
Date: Fri, 26 Mar 2004 16:34:20 -0500

>>2.IGMP snooping switch which performs proxy-reporting also --
>>
>>For performing proxy function, according to draft 
>>proxy-04.txt, we must have
>>only one upstream interface and it works only in tree topology.
>>a) Does this imply, we cannot implement proxy function in a 
>>IGMP snooping switch when there are more than one router 
>>ports? But the draft snoop-10.txt section 2.1.1  statement 2), 
>>states that IGMP snooping switches may also implement 
>>proxy function.
>>    
>>
>
>This is a question for the Proxy Draft author. Haixiang?
>
I am using this thread to address the comment I made during in MAGMA 
meeting so we can have a context.

I don't think the above issue is a Proxy problem. When there are more 
than one router ports on a Snooping switch, IMO there are two ways to 
use the proxy. The first solution is static configuration and assign one 
port as the upstream interface and others as downstream interface(s). 
This solution breaks the network into two separate networks. The second 
solution which I personally prefer is to treat all router ports as one 
upstream interface. All routers are on the same network even with the 
snooping switch. The reports have to be sent to all router ports. I 
think this is what a Snooping switch does in the first place.

I raised the issue back in Atlanta MAGMA meeting that the Snooping draft 
is not clear on what the suggested solution(s) is(are). Somehow my 
comment was not addressed. I understand it may be too late to make any 
technical change. But I think it would be nice if the Snooping draft can 
clarify this even though this may just be considered as an 
implementation issue.

If everyone likes the second solution, I suggest the following change:

     2)  IGMP snooping switches may also implement "proxy-reporting" in
         which reports received from downstream hosts are summarized and
         used to build internal membership states as described in
         [PROXY].  The IGMP proxy-reporting switch would then report its
         own state in response to upstream queriers <<to all ports that a normal IGMP Membership Report should be forwarded>>.  If the switch does
         not already have an IP address assigned to it, the source
         address for these reports should be set to all-zeros.

Any comment?

best regards,
Haixiang

---

From: Haixiang He <[email-masked]>
Date: Fri, 26 Mar 2004 16:34:20 -0500

Any comment?

best regards,
Haixiang