aguilera
10-30-2007, 08:50 AM
Sending Group Membership Queries
Only one router sends IGMP Query messages onto a particular link. This router is called the Querier. IGMPv1 depended on the multicast routing protocol to decide which router was the Querier.
IGMPv2 introduced a Querier election process, which works as follows.
By default, a router takes the role of Querier.
If a querier receives an IGMP Query message from a router on the same interface and with a lower IP address, it stops being the Querier.
If a router has stopped being the Querier, but does not receive an IGMP Query message within a configured interval, it becomes the Querier again.
Only one router sends IGMP Query messages onto a particular link. This router is called the Querier. IGMPv1 depended on the multicast routing protocol to decide which router was the Querier.
IGMPv2 introduced a Querier election process, which works as follows.
By default, a router takes the role of Querier.
If a querier receives an IGMP Query message from a router on the same interface and with a lower IP address, it stops being the Querier.
If a router has stopped being the Querier, but does not receive an IGMP Query message within a configured interval, it becomes the Querier again.