Mark,

According to this link, the current IOS versions do not switch when a v1 is
detected:

http://www.cisco.com/univercd/cc/td/doc/product/software/ios121/121cgcr/ip_c
/ipcprt3/1cdmulti.htm#xtocid28


Kent
""Vicuna, Mark""  wrote in message
[EMAIL PROTECTED]">news:[EMAIL PROTECTED]...
> they dont query both hosts.. thats why v2 is backwards compatible.  the
> igmp querier is 'switched off' when a v1 router is detected.
>
>
> hth,
> Mark.
> > -----Original Message-----
> > From: richard dumoulin [mailto:[EMAIL PROTECTED]]
> > Sent: Saturday, 17 August 2002 01:29
> > To: [EMAIL PROTECTED]
> > Subject: Re: Multicast DR and IGMP querier [7:51458]
> >
> >
> > Here it is !!   That was my confusion, because it seems that
> > this capability
> > was added in order to query IGMP version 1 hosts. With IGMP
> > version 2 it
> > seems you do not need it. But what happen then if you have
> > both IGMP v2 and
> > PIM DR's ?? Do they both query the hosts ?
> >
> > Any Multicast expert right there ?
> >
> > Regards.
> > ----- Original Message -----
> > From: "Kent Yu"
> > To: "richard dumoulin" ;
> > Sent: Friday, August 16, 2002 4:42 PM
> > Subject: Re: Multicast DR and IGMP querier [7:51458]
> >
> >
> > > Do you mean that in IOS if a router is running PIM and is
> > a DR, it will
> > > query even if it sees IGMP query messages from another
> > router with lower
> > ip
> > > address?
> > >
> > > Kent
> > >
> > > ----- Original Message -----
> > > From: "richard dumoulin"
> > > To: "Kent Yu" ;
> > > Sent: Friday, August 16, 2002 10:34 AM
> > > Subject: Re: Multicast DR and IGMP querier [7:51458]
> > >
> > >
> > > > RFC's are great, but have to look also at how Cisco IOS
> > implements the
> > > rfc.
> > > > PIM DR's use IGMP to query the hosts too !!
> > > >
> > > > Regards.
> > > > ----- Original Message -----
> > > > From: "Kent Yu"
> > > > To: "richard dumoulin" ;
> > > > Sent: Friday, August 16, 2002 4:20 PM
> > > > Subject: Re: Multicast DR and IGMP querier [7:51458]
> > > >
> > > >
> > > > > Richard,
> > > > >
> > > > > As we mentioned yesterday, only routers speak PIM, I am
> > not sure where
> > > you
> > > > > got the impression that PIM DRs query the hosts,
> > routers only use IGMP
> > > to
> > > > > query the hosts.
> > > > >
> > > > > I think as many have suggested, nothing is better than
> > reading the
> > > specs,
> > > > in
> > > > > this case, RFC 2117 should explain this pretty well.
> > > > >
> > > > > HTH
> > > > > Kent
> > > > >
> > > > > ----- Original Message -----
> > > > > From: "richard dumoulin"
> > > > > To:
> > > > > Sent: Friday, August 16, 2002 3:47 AM
> > > > > Subject: Re: Multicast DR and IGMP querier [7:51458]
> > > > >
> > > > >
> > > > > > Raj Santiago wrote:
> > > > > > >
> > > > > > > Hi Richard,
> > > > > > >
> > > > > > >
> > > > > > > Okay your question is basically what is a "IGMP querier and
> > > > > > > Multicast Designated Router"
> > > > > > >
> > > > > > >
> > > > > > > Igmp querier is the router in charge to see if any
> > hosts want
> > > > > > > to listen to a multicast stream.
> > > > > > >
> > > > > > > Designated Router is the router is charge to facilitate pim
> > > > > > > join, prune  and register messages(This also depends on the
> > > > > > > mode of pim your running, im being very abstract here);
> > > > > > > Basically the multicast routing part.
> > > > > >
> > > > > > But it seems to me that the DR will also query the hosts!!
> > > > > > >
> > > > > > >
> > > > > > > Under IGMP version 1, the router with the highest ip address
> > > > > > > was BOTH the IGMP querier and Designated Router.
> > > > > > >
> > > > > > > Under IGMP version 2, the router with highest ip
> > address is the
> > > > > > > DR and the router with the lowest ip address is the
> > IGMP querier.
> > > > > >
> > > > > > If I am right, both the DR and the querier will query
> > the hosts ??
> > > > > >
> > > > > >
> > > > > > Cheers.
> > [EMAIL PROTECTED]




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