Owner's Manual

Chapter 27. Multicast Routing and Switching | 724

27. Multicast Routing and Switching

This chapter includes the following sections:

• Overview on page 724

• Multicast Routing Table and RPF Overview on page 725

• PIM Overview on page 726

• IGMP Overview on page 733

• Configuring IP Multicast Routing on page 738

• Multicast VLAN Registration on page 748

• Displaying Multicast Information on page 756

• Troubleshooting PIM on page 757

For more information on IP multicasting, see the following publications:

• RFC 1112—Host Extension for IP Multicasting

• RFC 2236—Internet Group Management Protocol, Version 2

• PIM-DM Version 2—draft_ietf_pim_v2_dm_03

• RFC 2362—Protocol-Independent Multicast - Sparse Mode (PIM-SM): Protocol

Specification

The following URL points to the website for the IETF PIM Working Group:

http://www.ietf.org/html.charters/pim-charter.html

Overview

Multicast routing and switching is the functionality of a network that allows a single host (the

multicast server) to send a packet to a group of hosts. With multicast, the server is not forced to

duplicate and send enough packets for all the hosts in a group. Instead, multicast allows the

network to duplicate the packet where needed to supply the group. Multicast greatly reduces the

bandwidth required to send data to a group of hosts. IP multicast routing is a function that allows

multicast traffic to be forwarded from one subnet to another across a routing domain.