Multicast Addresses - HP 5920 series Configuration Manual

Multicast addresses

IP multicast addresses
• IPv4 multicast addresses:
IANA assigned the Class D address block (224.0.0.0 to 239.255.255.255) to IPv4 multicast.
Table 2 Class D IP address blocks and description
Address block
224.0.0.0 to 224.0.0.255
224.0.1.0 to 238.255.255.255
239.0.0.0 to 239.255.255.255
NOTE:
"Glop" is a mechanism for assigning multicast addresses between different ASs. By filling an AS number
into the middle two bytes of 233.0.0.0, you get 255 multicast addresses for that AS. For more
information, see RFC 2770.
Table 3 Some reserved multicast addresses
Address
224.0.0.1
224.0.0.2
224.0.0.3
224.0.0.4
224.0.0.5
224.0.0.6
224.0.0.7
224.0.0.8
224.0.0.9
224.0.0.11
224.0.0.12
224.0.0.13
Description
All systems on this subnet, including hosts and routers.
All multicast routers on this subnet.
Unassigned.
DVMRP routers.
OSPF routers.
OSPF designated routers and backup designated routers.
Shared Tree (ST) routers.
ST hosts.
RIPv2 routers.
Mobile agents.
DHCP server/relay agent.
All Protocol Independent Multicast (PIM) routers.
Description
Reserved permanent group addresses. The IP address 224.0.0.0 is
reserved. Other IP addresses can be used by routing protocols and
for topology searching, protocol maintenance, and so on.
lists common permanent group addresses. A packet destined for an
address in this block will not be forwarded beyond the local subnet
regardless of the TTL value in the IP header.
Globally scoped group addresses. This block includes the following
types of designated group addresses:
•
232.0.0.0/8—SSM group addresses.
•
233.0.0.0/8—Glop group addresses.
Administratively scoped multicast addresses. These addresses are
considered locally unique rather than globally unique. You can
reuse them in domains administered by different organizations
without causing conflicts. For more information, see RFC 2365.
6
Table 3