Reference Manual for the Model RP614 Web Safe Router
Network and Routing Basics B-3
There are fivestandard classes of IP addresses. These address classes have different ways of
determiningthe network and host sections of the address, allowing for different numbersof 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 h as been determined, the software
can correctly identify the host section of the address. The follo w figure shows the three main
addressclasses, including network and host sections of the address for each address type.
Figure B-1. Three Main Address Classes
The five address classes are:
• ClassA
Class A addressescan have up to 16,777,214 hosts on a single network. They use an eight-bit
network numberand a 24-bit node number. Class A addresses are in this range:
1.x.x.x to 126.x.x.x.
• ClassB
Class B addressescan have up to 65,354 hosts on a network. A Class B address uses a 16-bit
network numberand a 16-bit node number. Class B addresses are in this range:
128.1.x.x to 191.254.x.x.
• ClassC
Class C addressescan have 254 hosts on a network. Class C addresses use 24 bits for the
network addressand eight bits for the node. They are in this range:
192.0.1.x to 223.255.254.x.
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1
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lass A
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etwork Node
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lass C
Network Node
Network Node