Microsoft ES4612 User Manual
Multicast Filtering
3-153
3
Based on the group membership information learned from IGMP, a router/switch can
determine which (if any) multicast traffic needs to be forwarded to each of its ports.
At Layer 3, multicast routers use this information, along with a multicast routing
protocol such as DVMRP or PIM, to support IP multicasting across the Internet.
determine which (if any) multicast traffic needs to be forwarded to each of its ports.
At Layer 3, multicast routers use this information, along with a multicast routing
protocol such as DVMRP or PIM, to support IP multicasting across the Internet.
Note that IGMP neither alters nor routes IP multicast packets. A multicast routing
protocol must be used to deliver IP multicast packets across different subnetworks.
Therefore, when DVMRP or PIM routing is enabled for a subnet on this switch, you
also need to enable IGMP.
protocol must be used to deliver IP multicast packets across different subnetworks.
Therefore, when DVMRP or PIM routing is enabled for a subnet on this switch, you
also need to enable IGMP.
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 IGMP Query (page 3-154) to
monitor IGMP service requests passing between multicast clients and servers, and
dynamically configure the switch ports which need to forward multicast traffic.
in your network, you can use IGMP Snooping and IGMP Query (page 3-154) 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 3-157). 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.
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 3-157). 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 3-159).
more carefully, you can manually assign a multicast service to specific interfaces on
the switch (page 3-159).
IGMP Query (Layer 2 or 3) – IGMP Query can only be enabled globally at Layer 2,
but can be enabled for individual VLAN interfaces at Layer 3 (page 3-159). However,
note that Layer 2 query is disabled if Layer 3 query is enabled.
but can be enabled for individual VLAN interfaces at Layer 3 (page 3-159). However,
note that Layer 2 query is disabled if Layer 3 query is enabled.
L3 - network core
(multicast routing)
(multicast routing)
L2 - edge switches
(snooping and query)
(snooping and query)
L2 switch to end nodes
(snooping on IGMP clients)
(snooping on IGMP clients)