SMC Networks SMC6624M Switch User Manual


 
9-88
Configuring Advanced Features
Multimedia Traffic Control with IP Multicast (IGMP)
Configuring Advanced
Features
Multimedia Traffic Control with IP
Multicast (IGMP)
IGMP Features
In a network where IP multicast traffic is transmitted for various multimedia
applications, you can use the switch to reduce unnecessary bandwidth usage
on a per-port basis by configuring IGMP (Internet Group Management Proto-
col controls). In the factory default state (IGMP disabled), the switch forwards
all IGMP traffic to all ports, which can cause unnecessary bandwidth usage
on ports not belonging to multicast groups. Enabling IGMP allows the ports
to detect IGMP queries and report packets and manage IP multicast traffic
through the switch.
IGMP is useful in multimedia applications such as LAN TV, desktop confer-
encing, and collaborative computing, where there is multipoint communica-
tion; that is, communication from one to many hosts, or communication
originating from many hosts and destined for many other hosts. In such
multipoint applications, IGMP will be configured on the hosts, and multicast
traffic will be generated by one or more servers (inside or outside of the local
network). Switches in the network (that support IGMP) can then be config-
ured to direct the multicast traffic to only the ports where needed. If multiple
VLANs are configured, you can configure IGMP on a per-VLAN basis.
Feature Default Menu CLI Web
view igmp configuration n/a page 9-90
show igmp status for multicast
groups used by the selected
VLAN
n/a Yes
enabling or disabling IGMP
(Requires VLAN ID Context)
disabled page 9-92 page 9-94
per-port packet control auto page 9-93
IGMP traffic priority normal page 9-93
querier enabled page 9-94