Configuring Igmp Snooping; Overview; Basic Igmp Snooping Concepts - HP MSR2003 Configuration Manual

Configuring IGMP snooping

In this chapter, "MSR2000" refers to MSR2003. "MSR3000" collectively refers to MSR3012, MSR3024,
MSR3044, MSR3064. "MSR4000" collectively refers to MSR4060 and MSR4080.

Overview

IGMP snooping runs on a Layer 2 switch as a multicast constraining mechanism to improve multicast
forwarding efficiency. It creates Layer 2 multicast forwarding entries from IGMP packets that are
exchanged between the hosts and the router.
As shown in
to all hosts. When IGMP snooping is enabled, the Layer 2 switch forwards multicast packets of known
multicast groups to only the receivers.
Figure 10 Multicast packet transmission without and with IGMP snooping
The switch in this document refers to an MSR router installed with Layer 2 Ethernet interface modules.

Basic IGMP snooping concepts

IGMP snooping related ports
As shown in
receivers in a multicast group.
Figure 10, when IGMP snooping is not enabled, the Layer 2 switch floods multicast packets
Figure 1 1, IGMP snooping runs on Switch A and Switch B, and Host A and Host C are
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