Configuring IP Multicast Switching
IPMS Overview
OmniSwitch AOS Release 7 Network Configuration Guide
June 2013
page 24-7
Reserved IP Multicast Addresses
The Internet Assigned Numbers Authority (IANA) created the range for multicast addresses, which is
224.0.0.0 to 239.255.255.255. However, as the table below shows, certain addresses are reserved and
cannot be used.
IP Multicast Routing
IP multicast routing can be used for IP Multicast Switching and Routing (IPMSR). IP multicast routing is
a way of controlling multicast traffic across networks. The IP multicast router discovers which networks
want to receive multicast traffic by sending out Internet Group Management Protocol (IGMP) queries and
receiving IGMP reports from attached networks. The IGMP reports signal that users want to join a multi-
cast group.
If there is more than one IP multicast router in the network, the router with the lowest IP address is elected
as the querier router, which is responsible for querying the subnetwork for group members.
The IP multicast routing package provides the following two separate protocols:
•
Protocol Independent Multicast — Sparse Mode (PIM-SM) and Dense Mode (PIM-DM), which is
described in
•
Distance Vector Multicast Routing Protocol (DVMRP), which is described in
.
The multicast routing protocols build and maintain a multicast routing database. The multicast routing
protocols forward multicast traffic to
networks
that have requested group membership to a specific multi-
cast group. IPMS uses decisions made by the routing protocols and forwards multicast traffic to
ports
that
request group membership. See the
OmniSwitch AOS Release 7 Advanced Routing Configuration Guide
for more information on IP multicast routing protocols.
Address or Address Range
Description
224.0.0.0 through 224.0.0.255
Routing protocols (e.g., OSPF, RIP2)
224.0.1.0 through 224.0.1.255
Internetwork Control Block (e.g., RSVP, DHCP, commer-
cial servers)
224.0.2.0 through 224.0.255.0
AD-HOC Block (e.g., commercial servers)
224.1.0.0 through 224.1.255.255
ST Multicast Groups
224.2.0.0 through 224.2.255.255
SDP/SAP Block
224.252.0.0 through 224.255.255.255
DIS Transient Groups
225.0.0.0 through 231.255.255.255
Reserved
232.0.0.0 through 232.255.255.255
Source Specific Multicast
233.0.0.0 through 233.255.255.255
GLOP Block
234.0.0.0 through 238.255.255.255
Reserved
239.0.0.0 through 239.255.255.255
Administratively Scoped