R3102-R3103-HP 6600/HSR6600 Routers IP Multicast Configuration Guide

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Figure 12 IGMP snooping related ports
As shown in Figure 12, IGMP snooping divides the ports on the router into the following types:
• Router port—Layer 3 multicast device-side port. Layer 3 multicast devices include designated
routers and IGMP queriers. In the figure, GigabitEthernet 1/0/1 of Router B and GigabitEthernet
1/0/1 of Router C are router ports. The router registers all its local router ports in its router port list.
Do not confuse the "router port" in IGMP snooping with the "routed interface" commonly known as
the "Layer 3 interface." The router port in IGMP snooping is the Layer 2 interface.
• Member port—Multicast receiver-side port. In the figure, GigabitEthernet 1/0/2 and
GigabitEthernet 1/0/3 of Router B and GigabitEthernet 1/0/2 of Router C are member ports. The
router registers all the member ports on the local device in its IGMP snooping forwarding table.
Unless otherwise specified, router ports and member ports in this document include both static and
dynamic router ports and member ports.
Dynamic router ports include ports that receive IGMP general queries with the source IP address other
than 0.0.0.0 and ports that receive PIM hello messages. For more information about PIM hello messages,
see "Configuring PIM."
Aging timers for dynamic ports in IGMP snooping and related messages and actions
Timer Description
Message before
ex
p
iration
Action after expiration
Dynamic router port
aging timer.
For each dynamic router port,
the router sets an aging timer.
When the timer expires, the
dynamic router port ages out.
IGMP general query of
which the source address
is not 0.0.0.0 or PIM
hello.
The router removes this
port from its router port
list.
Dynamic member
port aging timer.
When a port dynamically
joins a multicast group, the
router starts an aging timer for
the port. When the timer
expires, the dynamic member
port ages out.
IGMP membership
report.
The router removes this
port from the IGMP
snooping forwarding
table.