IP Address

IP ADDRESS:

An Internet Protocol address (IP address) is usually a numerical label assigned to each device (e.g., computer, printer) participating in a computer network that uses the Internet Protocol for communication. An IP address serves two principal functions:

• Network address uniquely identifies the network.

• Node/Host address uniquely identifies each machine.

The designers of the Internet Protocol defined an IP address as a 32-bit numberk nown as Internet Protocol Version 4 (IPv4), is still in use today. However, due to the enormous growth of the Internet and the predicted depletion of available addresses, a new addressing system (IPv6), using 128 bits for the address,was also developed.

Classes of IP Addressing

Class ‘A’ (1 - 126) ,used for data communication

Class ‘B’ (128 - 191) ,used for data communication

Class ‘C’ (192 - 223) ,used for data communication

Class ‘D’ (224 - 239) ,used for multi casting

Class ‘E’ (240 - 255) ,research and testing purposes

Class	Leading Address Bit	Range of first octet	Network ID format	Host ID format	Number of Networks	Number of Addresses	Subnet Mask
A	0	1-126	a	b.c.d	27 = 128	224 = 16777216	255.0.0.0
B	10	128-191	a.b	c.d	214 = 16384	216 = 65536	255.255.0.0
C	110	192-223	a.b.c	d	221 = 2097152	28 = 256	255.255.255.0

Subnetting

• To create subnetworks, take bits from host portion to network i.e. subnet

• Determine the required network ID

• Determine the host required per subnet

• One subnet mast for entire network

• Range of host ID

• Default subnet mask is used to determine the part of host address in IP address