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4.8
Multicast Filtering
For multicast filtering, JetNet 5020G uses IGMP Snooping technology. IGMP (Internet
Group Management Protocol) is an Internet Protocol that provides a way for internet device
to report its multicast group membership to adjacent routers. Multicasting allows one
computer on the internet to send data to a multitude of other computers that have identified
themselves as being interested in receiving the originating computers data.
Multicasting is useful for such applications as updating the address books of mobile
computer users in the field, sending out newsletters to a distribution list, and broadcasting
streaming media to an audience that has tuned into the event by setting up multicast group
membership.
In effect, IGMP Snooping manages multicast traffic by making use of switches, routers, and
hosts that support IGMP. Enabling IGMP Snooping allows the ports to detect IGMP queries,
report packets, and manage multicast traffic through the switch. IGMP has three
fundamental types of messages, as shown below:
Message
Description
Query
A message sent from the querier (an IGMP router or a switch) which
asks for a response from each host that belongs to the multicast group.
Report
A message sent by a host to the querier to indicate that the host wants
to be or is a member of a given group indicated in the report message.
Leave Group
A message sent by a host to the querier to indicate that the host has
quit as a member of a specific multicast group.
You can enable
IGMP Snooping
and
IGMP Query
functions here. You will see the
information of the IGMP Snooping function in this section, including different multicast
groups’ VID and member ports, and IP multicast addresses that range from 224.0.0.0 to
239.255.255.255.
In this section, Force filtering can determined whether the switch flooding unknown
multicast or not.
Following commands are included in this group:
4.8.1 IGMP Snooping
4.8.2 IGMP Query
4.8.3 Unknown Multicast
4.8.4 GMRP Configuration
4.8.5 CLI Commands of the Multicast Filtering
4.8.1
IGMP Snooping
This page is to enable IGMP Snooping feature, assign IGMP Snooping for specific VLAN,
and view IGMP Snooping table from dynamic learnt or static manual key-in. JetNet 5020G
supports IGMP snooping V1/V2/V3 and IGMP query V1/V2.
IGMP Snooping,
you can select
Enable
or
Disable
here. After enabling IGMP Snooping,
you can then enable IGMP Snooping for specific VLAN. You can enable IGMP Snooping
for some VLANs so that some of the VLANs will support IGMP Snooping and others won’t.
To assign IGMP Snooping to VLAN, please select VLAN ID to enable/disable IGMP
