User manual

Addressing Schemes B-11
Supernet 3 requires an even multiple of 8. It also can begin on
the next available address.
Since supernet 4 can fit entirely in a single Class C address
space, it can use supernet 3’s surplus space. It is therefore given
the last Class C address space in Supernet 3’s territory,
effectively reducing supernet 3 to only the 7 class C networks it
needs.
Supernetting and the NETServer
In order to define a supernet on the NETServer, you must add
the network address and its netmask. You have two options
with NETServer. The first option permits you to set the subnet
via numerical (8-30 bits) designation. For example:
add ip network houston 192.75.202.99/23
Secondly, you can specify a class designation: A, B or C. You can
also leave the subnet value blank and let the NETServer choose
it for you. In this case, however, NETServer will specify a class
setting based on the IP address. For example:
add ip network houston 192.75.202.99/C
Note: To avoid confusion when configuring an IP address and subnet
mask, be aware that a dialup client’s subnet class designator is
specified as /h (host). This occurs by default with pool addresses
and specified addresses, as well as addresses learned from the
client. The h designates a mask of all 1 bits (255.255.255.255).
This value can be used only when the station being identified is
a host. Networked nodes still require class or numeric (8-32 bits)
subnets. For example:
set network user houston remote_ip_address 234.170.168.1/h