3Com 7757 Configuration Manual page 418

418 C 41: M
HAPTER ULTICAST
O
VERVIEW
A multicast group whose addresses are assigned by IANA is a permanent
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multicast group. It is also called reserved multicast group.
Note that:
The IP addresses of a permanent multicast group keep unchanged, while the
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members of the group can be changed.
There can be any number of, or even zero, members in a permanent multicast
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group.
Those IP multicast addresses not assigned to permanent multicast groups can
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be used by temporary multicast groups.
Class D IP addresses range from 224.0.0.0 to 239.255.255.255. For details, see
Table 328.
Table 328 Range and description of Class D IP addresses
Class D address range
224.0.0.0 to 224.0.0.255
224.0.1.0 to 231.255.255.255
233.0.0.0 to 238.255.255.255
232.0.0.0 to 232.255.255.255
239.0.0.0 to 239.255.255.255
As specified by IANA, the IP addresses ranging from 224.0.0.0 to 224.0.0.255 are
reserved for network protocols on local networks. The following table lists
commonly used reserved IP multicast addresses:
Table 329 Reserved IP multicast addresses
Class D address range
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
224.0.0.14
224.0.0.15
Description
Reserved multicast addresses (IP addresses for
permanent multicast groups). The IP address 224.0.0.0 is
reserved. Other IP addresses can be used by routing
protocols.
Available any-source multicast (ASM) multicast addresses
(IP addresses of temporary groups). They are valid for the
entire network.
Available source-specific multicast (SSM) multicast group
addresses.
Local management multicast addresses, which are used
in the local use only.
Description
Address of all hosts
Address of all multicast routers
Unassigned
Distance vector multicast routing protocol (DVMRP) routers
Open shortest path first (OSPF) routers
Open shortest path first designated routers (OSPF DR)
Shared tree routers
Shared tree hosts
RIP-2 routers
Mobile agents
DHCP server / relay agent
All protocol independent multicast (PIM) routers
Resource reservation protocol (RSVP) encapsulation
All core-based tree (CBT) routers