Dell C1048P Port Extender Networking Configuration Guide for the C9000 Series - Page 401

IGMP Version 3 Conceptually, IGMP version 3 behaves the same as version 2. However, there are differences. • Version 3 adds the ability to filter by multicast source, which helps multicast routing protocols avoid forwarding traffic to subnets where there are no interested receivers. • To enable filtering, routers must keep track of more state information, that is, the list of sources that must be filtered. An additional query type, the Group-and-Source-Specific Query, keeps track of state changes, while the Group-Specific and General queries still refresh the existing state. • Reporting is more efficient and robust: hosts do not suppress query responses (non-suppression helps track state and enables the immediate-leave and IGMP snooping features), state-change reports are retransmitted to insure delivery, and a single membership report bundles multiple statements from a single host, rather than sending an individual packet for each statement. The version 3 packet structure is different from version 2 to accommodate these protocol enhancements. Queries are still sent to the all-systems address 224.0.0.1, as shown in the following illustration, but reports are sent to the all IGMP version 3capable multicast routers address 244.0.0.22, as shown in the second illustration. Figure 43. IGMP Version 3 Packet Structure Figure 44. IGMP Version 3-Capable Multicast Routers Address Structure Internet Group Management Protocol (IGMP) 401