gateway
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... TCP, network wanted to create a mail gateway. If the
company was called X.COM, and IP/TCP capable ...
... . If the
company was called X.COM, and IP/TCP capable gateway machine was called
A.X.COM, the following RRs might be entered into the COM zone:
...
... resolver which becomes separated from the rest of the network due to a
link failure or gateway problem, or less often by coincident failure or
unavailability of all servers for a particular domain.
...
... allow the resolver to continue to resolve local names if the local
network becomes isolated from the internet due to gateway or link
failure.
...