Huawei DR814Q 9.2 Subnet Mask

User Manual

Aolynk DR814Q ADSL2+ Broadband Router 9 Appendix – IP Address and Subnet Mask

ields of a host ID can be 0s or 255s as these numbers are reserved for

special use.

9.2 Subnet Mask

z Not all the f

 Note:

A network mask looks like a regular IP address and a subnet mask can tell the division

f the network ID and the host ID: A bit set to 1 means this bit is part of the network ID o

and a bit set to 0 means this bit is part of the host ID.

Subnet masks are used to define subnets For example, to divide a Class C address

ield 4 is also included. Since this

net

hosts

s in field4 can have four values (00, 01, 10, and 11), so there are four

nets. Each subnet uses the remaining six bits in field 4 for its host IDs, ranging from

192.168.1.0 into two subnets, you need to set the subnet mask as follow

255.255.255.128

It is much more straightforward to define the address in binary notation.

11111111. 11111111 . 11111111.1 000 0000

For any Class C address, all the bits in the filed 1 through field 3 are part of the network

ID, but note how the mask specifies that the first bit in f

extra bit has only two values (0 and 1), this means there are two subnets. Each sub

uses the remaining 7 bits in field 4 for its host IDs, which range from 1 to 126

(instead of the usual 0 to 255 for a Class C address).

Similarly, to divide a class C network into four subnets, set the mask as follows:

255.255.255.192 or 11111111. 11111111. 11111111.11000000

The two extra bit

sub

1 to 62.

 Note:

S metimes a subnet maso k does not specify any additional network ID bits, and thus no

b is called a default subnet mask. These masks are:

B: 255.255.0.0

z Class C: 255.255.255.0

hey are so called because they are used for an initially configured network without

subnets.

su nets exist. Such a mask

z Class A: 255.0.0.0

z Class