Optional. Defaults:
o Destination is classified based on its Internet network class
(A, B, or C).
o If the address is clearly a network number, SET ROUTE
interprets the number correctly.
Defines the route as a network route.
Use this qualifier if the network number could be misinterpreted
as an IP host address; for example, if a network mask is
nonstandard, or if the IP address is abbreviated.
This qualifier is required if you are creating a network route
that specifies a CIDR mask (for example, /MASK=mask_length).