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Edimax Technology ES-5240G+ User Manual

Page 24

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In this diagram, you can see the subnet mask with 25-bit long,

255.255.255.128, contains 126 members in the sub-netted network. Another is that
the length of network prefix equals the number of the bit with 1s in that subnet mask.
With this, you can easily count the number of IP addresses matched. The following
table shows the result.

Prefix Length No. of IP matched No. of Addressable IP

/32 1

-

/31 2

-

/30 4

2

/29 8

6

/28 16

14

/27 32

30

/26 64

62

/25 128

126

/24 256

254

/23 512

510

/22 1024

1022

/21 2048

2046

/20 4096

4094

/19 8192

8190

/18 16384

16382

/17 32768

32766

/16 65536

65534

Table 2-3

There will be a maximum of 254 effective nodes exist along the sub-netted

network. This network is considered to be a physical autonomous network that it
owns a network IP address which may look like 168.1.2.0.

With the subnet mask, a big network can be divided into smaller pieces of

network. If we want to have more than two independent networks in a worknet, a
partition to the network must be performed. In this case, subnet mask must be
applied.