Multicast Filtering - Comtrol ROCKETLINX ES8509-XT User Manual

Configuration Using the Web Interface

Multicast Filtering

For multicast filtering, the ES8509-XT uses IGMP (Internet Group Management Protocol) Snooping
technology. IGMP 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 computer's
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 in the
following table.
Messages
Query
Report
Leave Group
You can enable IGMP Snooping and IGMP Query functions. This section illustrates the information of the
IGMP Snooping function, including different multicast groups' VID and member ports, and IP multicast
addresses that range from 224.0.0.0 to 239.255.255.255.
The following web pages are included in this group:
• IGMP Query on Page 101
• IGMP Snooping on Page 102
• GMRP Configuration
Optionally, you can use the CLI for configuration, see
100 - Multicast Filtering
A message sent from the querier (an IGMP router or a switch) that asks for
a response from each host that belongs to the multicast group.
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.
A message sent by a host to the querier to indicate that the host has quit as
a member of a specific multicast group.
on Page 103
Multicast Filtering (CLI)
RocketLinx ES8509-XT User Guide: 2000557 Rev. D
on Page 171.