Subnetwork Mask - Hitachi CMU Series User Manual

5 USER GUIDE

5.4.3 Subnetwork mask

When splitting an IP address into subnetworks, define the boundary between subnetwork number
and local host number by a subnetwork mask. If a subnetwork mask is used with other than the
default value, the address is the broadcast address as shown in the example below.
Example: For class B:
IP address
128.123.000.001
128.123.001.001
Subnetwork mask
255.255.000.000
255.255.255.000
5-14
Broadcast address
128.123.255.255
128.123.001.255