Transition Networks
S4224 Web User Guide
33558 Rev. C
Page 472 of 669
Monitor > IPMC > IGMP Snooping
The
Monitor
>
IPMC
>
IGMP
Snooping
menu path provides the Status, Groups Information, and IPv4
SFM Information sub-menus.
The IGMP (Internet Group Management Protocol) communications protocol is used to manage the
membership of Internet Protocol multicast groups. IGMP is used by IP hosts and adjacent multicast
routers to establish multicast group memberships. It is an integral part of the IP multicast specification,
like ICMP for unicast connections. IGMP allows more efficient use of resources when supporting uses
such as online video.
IGMP Snooping Status
This page provides IGMP Snooping status in terms of statistics and router port status.
The IPMC Snooping status
Statistics
information is explained below.
The VLAN ID of the entry (e.g., VLAN ID 1).
Querier Version
The working Querier Version currently in use (e.g.,
v3
shown above). In order for IGMP, and IGMP
snooping, to function, a multicast router must exist on the network and generate IGMP queries. The
tables created for snooping that (hold the member ports for a multicast group) are associated with the
querier. Without a querier, the tables are not created and snooping does not work. IGMP general
queries must be unconditionally forwarded by all switches involved in IGMP snooping.
Host Version
The working Host Version currently in use (e.g.,
v3
shown above).
Three versions of IGMP exist - versions
v1
,
v2
, and
v3
. One difference between the versions is how
a host node signals that it no longer wants to be a member of a multicast group.
In
v1
, the host node stops sending reports. If a router does not receive a report from a host node
after a predefined length of time (time-out value) it assumes that the host node no longer wants to
