Perle Systems 1700 User Manual

Page 24

Applications

The P1705 & P1730 allows mask sizes from 8 to 32 bits. The subnet mask size determines

how many bits of the host field of the original IP network address will be used for the

creation of subnets. In this example, specifying a mask size of 26 will produce a subnet size

of 2 bits. Two bits gives 4 possible sub-network addresses from the original IP network

address. Two of the resulting sub-networks will have either all zeros or all ones as the subnet

address; these addresses are reserved for network functions and hence are invalid addresses.

The subnet mask for the above example networks will be 255.255.255.192:

So setting a subnet mask size of 26 will generate two sub-networks with up to 62 host

addresses each (64 potential addresses minus the all zero and all one addresses). The new IP

sub-network addresses will be: 199.169.100.64 and 199.169.100.128.

Figure 2 -2 Defining an IP Subnet Mask

1. IP Address

Location: Main

Configuration

LAN Set up

LAN IP Set up

IP Address / Size of Subnet Mask

Original IP Network Address 199.169.100.0

Subnet IP Network Address

199.169.100.64
Subnet Mask Size 26

Router IP Address

199.169.100.65

Host IP Address
199.169.100.66

Host IP Address
199.169.100.67

Host IP Address
199.169.100.130

Host IP Address
199.169.100.131

Router IP Address
199.169.100.129

Subnet IP Network Address

199.169.100.128
Subnet Mask Size 26

Subnet Mask is
255.255.255.192

IP Computers

LAN #1

LAN #2