Xyplex Terminal Server 720 Manual page 49

INTERNET SUBNET
MASK
Example:
Xyplex>> DEFINE SERVER INTERNET SUBNET MASK AUTOCONFIGURE ENABLED
Xyplex>> DEFINE SERVER INTERNET SUBNET MASK 255.255.0.0
0021
Specifies the Internet subnet-mask for the terminal server.
The purpose of a subnet-mask is to assist the terminal server
in distinguishing Internet addresses that can be reached
directly from those that must be reached via an IP Gateway.
Each device running TCP protocols contains a subnet mask.
When a user attempts to form a TCP connection with a
destination Internet node, the destination Internet address
is logically ANDed with the subnet mask. The unit's own
Internet address is also logically ANDed with the subnet
mask. The two results of these operations are compared. If
they are equal, then the destination is assumed to be
reachable without the assistance of an IP Gateway. If they
are not equal, then the unit will attempt to reach the
destination via an IP Gateway.
The subnet-mask is defined using the same format as an
Internet address, with ones for the network and/or sub-
network portion(s).
You can also use the AUTOCONFIGURE option to specify
that the software will automatically determined the internet-
subnet-mask. When you allow the terminal server to
automatically determine the internet-subnet-mask, the
terminal server changes the internet-subnet-mask for
either the permanent or operational database whenever the
internet-address changes. AUTOCONFIGURE is the
default. If you plan to use sub-netting in your network, you
should not enable the AUTOCONFIGURE option.
Operation and Software Configuration
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