NETGEAR WGR826V manual Figure B-1 Three Main Address Classes

Reference Manual for the 54 Mbps Wireless Router with Phone Adapter WGR826V

There are five standard classes of IP addresses. These address classes have different ways of determining the network and host sections of the address, allowing for different numbers of hosts on a network. Each address type begins with a unique bit pattern, which is used by the TCP/IP software to identify the address class. After the address class has been determined, the software can correctly identify the host section of the address. The follow figure shows the three main address classes, including network and host sections of the address for each address type.

Class A

Network	Node
Class B
Network	Node
Class C

NetworkNode

Figure B-1: Three Main Address Classes

The five address classes are:

•Class A

Class A addresses can have up to 16,777,214 hosts on a single network. They use an eight-bit network number and a 24-bit node number. Class A addresses are in this range:

1.x.x.x to 126.x.x.x.

•Class B

Class B addresses can have up to 65,354 hosts on a network. A Class B address uses a 16-bit network number and a 16-bit node number. Class B addresses are in this range:

128.1.x.x to 191.254.x.x.

•Class C

Class C addresses can have 254 hosts on a network. Class C addresses use 24 bits for the network address and eight bits for the node. They are in this range:

192.0.1.x to 223.255.254.x.

Network, Routing, and Firewall Basics B-3

202-10051-01, March 2005