HP Vectra VL5 5 Network Manual page 6

Gateway: this is a router that will locate a route to your destination
on the network. This has no use on a local area network with no
need to access the Internet or a remote PC (that doesn't belong to
the same subnet, for example, if the distance is greater than
100m). This router is also helpful if you need to isolate some sub-
networks within your network.
Subnet mask: this allows you to define which IP addresses
should be considered in your sub-network and which ones should
not pass through the gateway.
Two PCs belonging to the same sub-network do not require an
external server (such as DNS or Gateways) to exchange data.
Subnet masks work by "bitwise" and a mask.
For example, PC A's IP address is 192.168.1.1; PC B's IP address
is 192.168.0.127; PC C's IP address is 192.168.3.1
If PC A's subnet is set to 255.255.254.0, then PC B is part of A's
sub-network:
192.168.1.1 and 255.255.254.0 = 192.168.0.0
192.168.0.127 and 255.255.254.0 = 192.168.0.0
Both are equal so PC A will consider PC B is part of the same
sub-network.
However, PC C is not part of the sub-network:
192.168.3.1 and 255.255.254.0 = 192.168.2.0
A subnet mask cannot be defined. If the mask is converted into
one binary number, there must only be a transition from 1 to 0 and
no transition from 0 to 1
For example, 255.255.254.0 = 1111 1111 1111 1111 1111 1110
0000 0000 is correct
255.0.255.255 = 1111 1111 0000 0000 1111 1111 1111 1111 is
incorrect as there is a transition from 0 to 1 after a transition from
1 to 0.
How do I check these settings?
6