Alcatel-Lucent 6850-48 Guida Di Rete
OmniSwitch AOS Release 6 Network Configuration Guide
September 2009
page 42-1
42 Configuring IP Multicast
Switching
IP Multicast Switching is a one-to-many communication technique employed by emerging applications,
such as video distribution, news feeds, conferencing, netcasting, and resource discovery (OSPF, RIP2, and
BOOTP). Unlike unicast, which sends one packet per destination, multicast sends one packet to all devices
in any subnetwork that has at least one device requesting the multicast traffic. Multicast switching also
requires much less bandwidth than unicast techniques and broadcast techniques, since the source hosts
only send one data stream to the ports on which destination hosts that request it are attached.
such as video distribution, news feeds, conferencing, netcasting, and resource discovery (OSPF, RIP2, and
BOOTP). Unlike unicast, which sends one packet per destination, multicast sends one packet to all devices
in any subnetwork that has at least one device requesting the multicast traffic. Multicast switching also
requires much less bandwidth than unicast techniques and broadcast techniques, since the source hosts
only send one data stream to the ports on which destination hosts that request it are attached.
Destination hosts signal their intent to receive a specific IP multicast stream by sending a request to do so
to a nearby switch by using Internet Group Management Protocol (IGMP). This is referred to as IGMP
Snooping. Destination hosts signal their intent to receive a specific IPv6 multicast stream by sending a
request to do so to a nearby switch by using Multicast listener discovery protocol (MLD). This is referred
to as MLD Snooping. The switch then learns on which ports multicast group subscribers are attached and
can intelligently deliver traffic only to the respective ports. Alcatel-Lucent’s implementation of IGMP
snooping is called IP Multicast Switching (IPMS) and MLD snooping is called IP Multicast Switching
version 6 (IPMSv6). IPMS/IPMSv6 allows switches to efficiently deliver multicast traffic in hardware at
wire speed.
to a nearby switch by using Internet Group Management Protocol (IGMP). This is referred to as IGMP
Snooping. Destination hosts signal their intent to receive a specific IPv6 multicast stream by sending a
request to do so to a nearby switch by using Multicast listener discovery protocol (MLD). This is referred
to as MLD Snooping. The switch then learns on which ports multicast group subscribers are attached and
can intelligently deliver traffic only to the respective ports. Alcatel-Lucent’s implementation of IGMP
snooping is called IP Multicast Switching (IPMS) and MLD snooping is called IP Multicast Switching
version 6 (IPMSv6). IPMS/IPMSv6 allows switches to efficiently deliver multicast traffic in hardware at
wire speed.
In This Chapter
This chapter describes the basic components of IPMS and how to configure them through the Command
Line Interface (CLI). CLI commands are used in the configuration examples; for more details about the
syntax of commands, see the OmniSwitch CLI Reference Guide.
Line Interface (CLI). CLI commands are used in the configuration examples; for more details about the
syntax of commands, see the OmniSwitch CLI Reference Guide.
Configuration procedures described in this chapter include:
• Enabling and disabling IP Multicast Switching and Routing on
• Configuring and removing an IGMP static neighbor on
.
• Configuring and removing an IGMP static querier on
.
• Modifying IPMS parameters beginning on
.
• Enabling and disabling IPv6 Multicast Switching and Routing on
.
• Configuring and removing an MLD static querier on
.
• Modifying IPMSv6 parameters beginning on
.