Specifications

164 VH-2402-L3 Management Guide 9033691-01
Multicast Groups
Class D IP addresses are assigned to a group of network
devices that comprise a multicast group. The four most
significant four bits of a Class D address are set to “1110”.
The following 28 bits is referred to as the ‘multicast group
ID’. Some of the range of Class D addresses are registered
with the Internet Assigned Numbers Authority (IANA) for
special purposes. For example, the block of multicast
addresses ranging from 224.0.0.1 to 224.0.0.225 is reserved
for use by routing protocols and some other low-level
topology discovery and maintenance protocols.
Figure 2-14. Class D Multicast Address
Some of the reserved IP multicast addresses are as follows:
Address Assignment
224.0.0.0
Base Address (reserved)
224.0.0.1
All Systems on this subnet
224.0.0.2
All Routers on this subnet
224.0.0.3
Unassigned
224.0.0.4
DVMRP Routers
224.0.0.5
OSPF IGP Routers
224.0.0.6
OSPF IGP Designated Routers
224.0.0.7
ST Routers