QTECH
Software Configuration Manual
10-128
239.0.0.0 to 239.255.255.255
Local management multicast addresses, which are for specific local use
only.
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 1-2 Reserved IP multicast addresses
Class D address range
Description
224.0.0.1
Address of all hosts
224.0.0.2
Address of all multicast routers
224.0.0.3
Unassigned
224.0.0.4
Distance vector multicast routing protocol (DVMRP) routers
224.0.0.5
Open shortest path first (OSPF) routers
224.0.0.6
Open shortest path first designated routers (OSPF DR)
224.0.0.7
Shared tree routers
224.0.0.8
Shared tree hosts
224.0.0.9
RIP-2 routers
224.0.0.11
Mobile agents
224.0.0.12
DHCP server/relay agent
224.0.0.13
All protocol independent multicast (PIM) routers
224.0.0.14
Resource reservation protocol (RSVP) encapsulation
224.0.0.15
All core-based tree (CBT) routers
224.0.0.16
The specified subnetwork bandwidth management (SBM)
224.0.0.17
All SBMS
224.0.0.18
Virtual router redundancy protocol (VRRP)
224.0.0.19 to 224.0.0.255
Other protocols
&
Note : Like having reserved the private network segment 10.0.0.0/8 for unicast,
IANA has also reserved the network segments ranging from 239.0.0.0 to 239.255.255.255
for multicast. These are administratively scoped addresses. With the administratively
scoped addresses, you can define the range of multicast domains flexibly to isolate IP
addresses between different multicast domains, so that the same multicast address can be
used in different multicast domains without causing collisions.
10.1.1.2
Ethernet multicast MAC address
When a unicast IP packet is transported in an Ethernet network, the destination MAC address is the MAC
address of the receiver. When a multicast packet is transported in an Ethernet network, a multicast MAC address is
used as the destination address because the destination is a group with an uncertain number of members.
As stipulated by IANA, the high-order 24 bits of a multicast MAC address are 0x01005e, while the low-order
23 bits of a MAC address are the low-order 23 bits of the multicast IP address. Figure below describes the mapping
relationship :