Planet Technology SGSD-1022 - Manual (Page 206)

User’s Manual of SGSD-1022 / SGSD-1022P
SGSW-2840 / SGSW-2840P
206
1. When the Managed Switch is configured to use IGMPv3 snooping, the snooping
version may be downgraded to version 2 or version 1, depending on the version of the
IGMP query packets detected on each VLAN.
2. IGMP snooping will not function unless a multicast router port is enabled on the
switch. This can be accomplished in one of two ways. A static router port can be
manually configured (see “ Specifying Static Interfaces for a Multicast Router ” ).
Using this method, the router port is never timed out, and will continue to function until
explicitly removed. The other method relies on the switch to dynamically create
multicast routing ports whenever multicast routing protocol packets or IGMP query
packets are detected on a port.
3. A maximum of up to 255 multicast entries can be maintained for IGMP snooping, and
255 entries for Multicast Routing, when both of these features are enabled. If the
table’s capacity is exceeded, the IGMPv3 snooping will not support multicast source
filtering, but will forward multicast traffic from all relevant sources to the requesting
hosts.
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. 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.
Configuring IGMP Snooping and Query Parameters
4.9.1.1 IGMP Configuration
You can configure the Managed Switch to forward multicast traffic intelligently. Based on the IGMP query and report messages,
the Managed Switch forwards traffic only to the ports that request multicast traffic. This prevents the Managed Switch from
broadcasting the traffic to all ports and possibly disrupting network performance.
Command Usage
„ IGMP Snooping –
This Managed 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.