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Multicast-Designated Forwarder and Querier

I'm getting some conflicting information on what becomes the DR (IGMP Querier)and the forwarder of multicast on a broadcast segment. Can someone verify this...

IGMPv1-uses routing protocol to determine DR(querier)

DR-highest IP on multicast router if PIM is used

Forwarder- highest IP on multicast router

IGMPv2-uses its own mechanism for querier role

DR(Queier)- Lowest IP address on multicast router (whether PIM is running or not)

Forwarder- Highest IP address on multicast router

IGMPv3-same as IGMPv2

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Silver

Re: Multicast-Designated Forwarder and Querier

Yes, with all versions of IGMP, only one router per IP subnet sends queries. This router is called the query router. In IGMPv1, the query router is chosen with the help of the multicast routing protocol. In IGMPv2 and IGMPv3, it is chosen by the lowest IP address among the routers.

1 REPLY
Silver

Re: Multicast-Designated Forwarder and Querier

Yes, with all versions of IGMP, only one router per IP subnet sends queries. This router is called the query router. In IGMPv1, the query router is chosen with the help of the multicast routing protocol. In IGMPv2 and IGMPv3, it is chosen by the lowest IP address among the routers.

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