CHAPTER
24-1
Software Configuration Guide—Release 12.2(25)SG
OL-7659-03
24
Understanding and Configuring IP Multicast
This chapter describes IP multicast routing on the Catalyst4500 series switch. It also provides
procedures and examples to configure IP multicast routing.
Note For complete syntax and usage information for the switch commands used in this chapter, refer to the
Catalyst 4500 Series Switch Cisco IOS Command Reference and related publications at
http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122cgcr/index.htm.
Note For more detailed information on IP multicast, refer to the discussion at:
http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122cgcr/fipr_c/ipcpt3/
This chapter includes the following major sections:
Overview of IP Multicast, page 24-1
Configuring IP Multicast Routing, page 24-12
Monitoring and Maintaining IP Multicast Routing, page 24-15
Configuration Examples, page 24-21

Overview of IP Multicast

This section includes these subsections:
IP Multicast Protocols, page 24-2
IP Multicast on the Catalyst 4500 Series Switch, page 24-4
Unsupported Features, page 24-12
At one end of the IP communication spectrum is IP unicast, where a source IP host sends packets to a
specific destination IP host. In IP unicast, the destination address in the IP packet is the address of a
single, unique host in the IP network. These IP packets are forwarded across t he network from the source
to the destination host by routers. At each point on the path between sourc e and destination, a router uses
a unicast routing table to make unicast forwarding decisions, based on the IP destination address in the
packet.