By the Server
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... client software; it should never be modified by the
client. In practice, the selector string is often a pathname or
other file selector used by the server to locate the item desired.
The next two tab delimited fields denote the domain-name of the host ...
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All intelligence is carried by the server implementation rather than
the protocol. What you build into more exotic servers is up to you.
Server implementations may grow as needs dictate and time allows.
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(a) Intelligence is held by the server. Clients have the option
of being able to access new document types ...