Multicast Address - UTStarcom iSpirit 3026 Manual

complex surroundings which will improve resource using rate. Mlticast technology is mainly
realized by IGMP protocol and multicast route protocol, among which IGMP protocol mainly
manages users about their entry and exit, but Multicastroute protocol is used for constructing
Multicast route between routers.
In this section definitions of IGMP are introduced, including:
●

Multicast Address

●
Multicast MAC Address
●
Two Special Multicast Address
●
Message Format of IGMPV2
1. Multicast Address
In the Internet, the communication forwarded between host machines in following different three
addresses:
●
Unicast address: it is the sole address of host machine in sub-net. e.g. IP address:
10.10.1. 9 or MA C address: 01:00: 5C: A0: 4A:B 1 。
● Broadcast address: it is used for sending data to all host machines in sub-net. e.g.
broadcast IP address is 192.168.100.255, MAC broadcast address: FF:FF:FF:FF:FF 。
●
Multicast address: through it to send data in packet to several host machines. IP
address is divided into three kinds of A, B, and C. The fouth i.e. D address is saved as
multicast address. In the IP protocol of Edition IV (IPv4), all IP addresses from 224.0.0.0 to
239.255.255.255 belong to the address D.
The high 4-digit of multicast address is the "1110" address, corresponding to decimalism is
224 to 239, other 28 digits are saved as multicast information, please refer to Figure 14-2:
the lower 28-digit is the multicast information.
Figure 14-2. Multicast Address