Perle Systems IOLINK-520 - Manual (Page 27)

Applications
IOLINK-520 & IOLINK-PRO Installation & Applications Guide — 2.7
The IOLINK-520 & IOLINK-PRO 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
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
IP Computers
LAN #1 LAN #2