SMC Networks SMC TigerStack IV SMC6224M - Manual (Page 239)

M
ULTICAST
F
ILTERING
3-185
Layer 2 IGMP (Snooping and Query)
IGMP Snooping and Query – If multicast routing is not supported on
other switches in your network, you can use IGMP Snooping and Query
(page 3-185) to monitor IGMP service requests passing between multicast
clients and servers, and dynamically configure the switch ports which need
to forward multicast traffic.
Static IGMP Router Interface – If IGMP snooping cannot locate the
IGMP querier, you can manually designate a known IGMP querier (i.e., a
multicast router/switch) connected over the network to an interface on
your switch (page 3-189). This interface will then join all the current
multicast groups supported by the attached router/switch to ensure that
multicast traffic is passed to all appropriate interfaces within the switch.
Static IGMP Host Interface – For multicast applications that you need to
control more carefully, you can manually assign a multicast service to
specific interfaces on the switch (page 3-192).
Configuring IGMP Snooping and Query Parameters
You can configure the switch to forward multicast traffic intelligently.
Based on the IGMP query and report messages, the switch forwards traffic
only to the ports that request multicast traffic. This prevents the switch
from broadcasting the traffic to all ports and possibly disrupting network
performance.
Command Usage
• IGMP Snooping – This switch can passively snoop on IGMP Query
and Report packets transferred between IP multicast routers/switches
and IP multicast host groups to identify the IP multicast group
members. It simply monitors the IGMP packets passing through it,
picks out the group registration information, and configures the
multicast filters accordingly.
• IGMP Querier – A router, or multicast-enabled switch, can
periodically ask their hosts if they want to receive multicast traffic. If
there is more than one router/switch on the LAN performing IP