Cisco Catalyst 3850 series Configuration Manual page 50

IP Multicast Address Scoping
Table 4: Multicast Address Range Assignments
Name
Reserved Link-Local Addresses
Globally Scoped Addresses
Source Specific Multicast
GLOP Addresses
Limited Scope Address
Reserved Link-Local Addresses
The IANA has reserved the range 224.0.0.0 to 224.0.0.255 for use by network protocols on a local network
segment. Packets with an address in this range are local in scope and are not forwarded by IP routers. Packets
with link local destination addresses are typically sent with a time-to-live (TTL) value of 1 and are not
forwarded by a router.
Within this range, reserved link-local addresses provide network protocol functions for which they are reserved.
Network protocols use these addresses for automatic router discovery and to communicate important routing
information. For example, Open Shortest Path First (OSPF) uses the IP addresses 224.0.0.5 and 224.0.0.6 to
exchange link-state information.
IANA assigns single multicast address requests for network protocols or network applications out of the
224.0.1.xxx address range. Multicast routers forward these multicast addresses.
Globally Scoped Addresses
Addresses in the range 224.0.1.0 to 238.255.255.255 are called globally scoped addresses. These addresses
are used to send multicast data between organizations across the Internet. Some of these addresses have been
reserved by IANA for use by multicast applications. For example, the IP address 224.0.1.1 is reserved for
Network Time Protocol (NTP).
Source Specific Multicast Addresses
Addresses in the range 232.0.0.0/8 are reserved for Source Specific Multicast (SSM) by IANA. In Cisco IOS
software, you can use the ip pim ssmcommand to configure SSM for arbitrary IP multicast addresses also.
SSM is an extension of Protocol Independent Multicast (PIM) that allows for an efficient data delivery
IP Multicast Routing Configuration Guide, Cisco IOS XE Release 3.6E (Catalyst 3850 Switches)
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Range
224.0.0.0 to 224.0.0.255
224.0.1.0 to 238.255.255.255
232.0.0.0 to 232.255.255.255
233.0.0.0 to 233.255.255.255
239.0.0.0 to 239.255.255.255
IP Multicast Routing Technology Overview
Description
Reserved for use by network protocols on
a local network segment.
Reserved to send multicast data between
organizations and across the Internet.
Reserved for use with the SSM datagram
delivery model where data is forwarded
only to receivers that have explicitly joined
the group.
Reserved for statically defined addresses
by organizations that already have an
assigned autonomous system (AS) domain
number.
Reserved as administratively or limited
scope addresses for use in private multicast
domains.
OL-32598-01