Tunneling
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... proxy tells the outside endpoint that
it will be tunneling. If the outside machine agrees, the proxy "gets
out of the way," simply passing octets transparently, and both the
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Once both endpoint machines are connected, the tunneling proxy
machine does no further interpretation of the data. In particular,
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... tunnel._tcp" MAY be used as a
default for finding the appropriate address for tunneling into a
particular domain.
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