Division Of IP Address Classes

For this time I will discuss about the IP address class divisions. The basic consideration of the Division of IP address into classes is to simplify the distribution of IP address registration

Version 4 IP address consists of 4 octets, and the value 1 octet is 255. Since there are 4 octet then the number of available IP address is 255 x 255 x 255 x 255. The IP address should be doled out as much as throughout the internet network users around the world. To ease the process of Division, the IP address should be grouped in classes.

IP address are grouped in five classes, namely class A, B, C, D, and e. the difference is in the size and number of. Class A network IP address. Class B IP address used for large and medium network. Class C IP address for the network Division of a lot, but each network has a few members. IP address Classes D and E are also defined, but is not used in normal usage, a class D multicast network intended for, and E for experimental.

Division of IP address classes are based on two things, namely the Network ID and Host ID of an IP address Any IP address is always a partner network ID (Network Id) and the Host ID (such as a host in a network). Each computer/router on a network host his ID must be unique (must be different with other PC/labtop yg).

Division Of IP Address Classes

Class A

Format 0nnnnnnn hhhhhhhh.. hhhhhhhh hhhhhhhh. (n = Net ID, h = Host ID)

The first bit is 0

Net ID length 8 bits (1 octet)

The length of the Host ID 24 bits (3 octets)

The first octets 0-127

The IP address range 1. xxx.xxx. xxx. up to 126. xxx.xxx. xxx (0 and 127 are reserved)

Network number 126

Number of IP address 16.777.214

Class A IP network for a bit with the host very much. How to read the class A IP address for example 113.46.5.6 is the Network ID Host ID: 113, = 46.5.6

Class B

The format nnnnnnnn hhhhhhhh.. 10nnnnnn. hhhhhhhh (n = Net ID, h = Host ID)
2 the first 10 bits
Net ID length 16 bits (2 octets)
Host ID length 16 bits (2 octets)
The first octets 128-191
The IP address range 128.0.0. xxx.xxx 191.255 until xxx.
The number of Network 16.384
Number of IP address 65.534

Commonly used for medium and large networks. the first two bits are always set to 10. the next 16 bits, class B IP network can accommodate approximately 65000 host.

The format nnnnnnnn hhhhhhhh.. 10nnnnnn. hhhhhhhh (n = Net ID, h = Host ID)
2 the first 10 bits
Net ID length 16 bits (2 octets)
Host ID length 16 bits (2 octets)
The first octets 128-191
The IP address range 128.0.0. xxx.xxx 191.255 until xxx.
The number of Network 16.384
The number of 65.534 class C IP address

The format nnnnnnnn nnnnnnnn.. 110nnnnn. hhhhhhhh (n = Net ID, h = Host ID)
the first 3 bits are 110
The length of the Net ID 24 bits (3 octets)
Host ID length 8 bits (1 octet)
The first octet of 192-223
The IP address range of 192.0.0 to 255.255.255. xxx. xxx
The number of Network 2.097.152
Number of IP address 254

The host ID is 8 bits terakhi, with class C IP, can be formed about 2 million network each have 256 IP address the first Three bit class C IP address always contains 111 21 bits with the next. The host ID is the last 8 bits.


Class D

Format 1110mmmm. mmmmmmmm. mmmmmmmm. mmmmmmmm
4 the first Bits 1110
28-bit multicast bit
The initials of the 224-247 bytes
Description of the Class D multicast address space is

This class is used for Multicasting purposes. 1110 first bit, 4 bit-the next bit is set according to the purposes of multicast group that uses this IP address. Unknown network multicasting in a bit and host bits.


Class E

Format 1111rrr. rrrrrrrr. rrrrrrrr. rrrrrrrr
the first 4 bit 1111
Spare bit 28 bit
The initials 248-255 bytes
Description of the Class E address space that is reserved for experimental purposes


Commonly used for medium and large networks. the first two bits are always set to 10. the next 16 bits, class B IP network can accommodate approximately 65000 host.