Draytek P2260 - page 23

VigorSwitch P2260 User’s Guide 17

For IP address configuration, there are three parameters needed to be filled in. They are IP

address, Subnet Mask, Default Gateway and DNS.

IP address:

The address of the network device in the network is used for internetworking

communication. Its address structure looks is shown below. It is “classful” because it is

split into predefined address classes or categories.

Each class has its own network range between the network identifier and host identifier in

the 32 bits address. Each IP address comprises two parts: network identifier (address) and

host identifier (address). The former indicates the network where the addressed host resides,

and the latter indicates the individual host in the network which the address of host refers to.

And the host identifier must be unique in the same LAN. Here the term of IP address we

used is version 4, known as IPv4.

Network identifier Host identifier

With the classful addressing, it divides IP address into three classes, class A, class B and

class C. The rest of IP addresses are for multicast and broadcast. The bit length of the

network prefix is the same as that of the subnet mask and is denoted as IP address/X, for

example, 192.168.1.0/24. Each class has its address range described below.

Class A:

Address is less than 126.255.255.255. There are a total of 126 networks can be defined

because the address 0.0.0.0 is reserved for default route and 127.0.0.0/8 is reserved for

loopback function.

Class B:

IP address range between 128.0.0.0 and 191.255.255.255. Each class B network has a

16-bit network prefix followed 16-bit host address. There are 16,384 (2^14)/16 networks

able to be defined with a maximum of 65534 (2^16 –2) hosts per network.

Class C:

IP address range between 192.0.0.0 and 223.255.255.255. Each class C network has a

24-bit network prefix followed 8-bit host address. There are 2,097,152 (2^21)/24 networks

able to be defined with a maximum of 254 (2^8 –2) hosts per network.

32 bits