C H A P T E R 2

Intel Express 460T Standalone Switch Users Guide

Internet Group Multicast Protocol (IGMP)

Generally, the switch broadcasts multicast traffic to all ports. For multicast traffic based on the TCP/IP using the IGMP protocol, the switch can optimize the broadcasting of multicast traffic by forwarding multicast traffic only to ports that require it.

IGMP Snooping is a feature that allows the switch to forward multicast traffic intelligently. The switch “snoops” the IGMP query and report messages and forwards traffic only to the ports that request the multicast traffic. This prevents the switch from broadcasting the traffic to all ports and possibly affecting network performance.

IGMP requires a router that detects multicast groups on its subnets and keeps track of group membership. Note that multicasting is not connection oriented, so data is delivered to the requesting hosts on a best-effort level of service.

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Intel 460T manual Internet Group Multicast Protocol Igmp