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
