Some Important information on IP Address.

By | July 10, 2009

Class A IP address is used for a network with large number of hosts.

Class B IP address is used for a network with medium number of hosts.

Class C IP address is used for a network with less number of hosts.

IP Address Class Possible range of IP address
Class A 0.0.0.0   through 127.255.255.255
Class B 128.0.0.0 through 191.255.255.255
Class C 192.0.0.0 through 223.255.255.255
Class D 224.0.0.0 through 239.255.255.255
Class E 240.0.0.0 through 247.255.255.255

The Class D IP addresses are used for multicasting.

The Class E IP addresses are reserved for experimental purpose.

The maximum number of networks and hosts that can be represented using the various IP address classes is shown below in the table:

IP Address Class Maximum number of N/W Maximum no of host per N/W
Class A 126 (2^7 – 2) 16777214 (2^24 – 2)
Class B 16384 (2^14) 65534 (2^16 – 2)
Class C 2097152 (2^21) 254 (2^8 – 2)
Class D ————————————— —————————————
Class E ————————————— —————————————

Some IP Address are not available for general internet use, They are used for special purpose:

IP Address Description
0.0.0.0 Local host.
127.xxx.xxx.xxx Local loopback address. The value of the last 3 bytes are ignored.  The datagram with this IP address is never transmitted over the network.
xxx.0.0.0

xxx.xxx.0.0

xxx.xxx.xxx.0

Local host IP address.  The x represents the network ID bits
0.xxx.xxx.xxx

0.0.xxx.xxx

0.0.0.xxx

IP address of a host in the local network.  The x represents the host ID bits.
255.255.255.255 Limited Broadcast address.  Datagram with this address will be received and processed by all the hosts in the local network.  This datagram is not forwarded to other networks by routers.
xxx.255.255.255

xxx.xxx.255.255

xxx.xxx.xxx.255

Directed broadcast address.  The datagram with this IP address is received by all the hosts in the specified network.  The x  represents the network ID bits