Lucent Technologies PortMaster 4, Руководство по настройке

Страница: 171 / 191

Networking Concepts A-3
Network Addressing
For example:
Class B Addresses
The class B IP address format allocates the highest 16 bits to the network field and sets
the two highest-order bits to 1 and 0, providing a range from 128 through 191,
inclusive. The remaining 16 bits form the host field. More than 16,000 class B networks
can exist, and each class B network can have up to 65,534 hosts. For example:
Class C Addresses
The class C IP address format allocates the highest 24 bits to the network field and sets
the three highest-order bits to 1, 1, and 0, providing a range from 192 through 223,
inclusive. The remaining 8 bits form the host field. More than two million class C
networks can exist, and each class C network can have up to 254 hosts. For example:
Class D Addresses
The class D IP address format was designed for multicast groups, as discussed in
RFC 1112. In class D addresses, the 4 highest-order bits are set to 1, 1, 1, and 0,
providing a range from 224 through 239, inclusive.
Class D addresses are currently used primarily for the multicast backbone (MBONE) of
the Internet. Many routers, including those from Lucent, do not support MBONE or
multicast and therefore ignore class D addresses.
10.100.232.1
Network
address
Host address
172.16.232.121
Network
address
Host address
192.168.20.220
Network
address
Host address