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User agent, Service agent, Client, Server

From: Jacob Palme <jpalme@dsv.su.se>
Date: Thu, 29 Jul 1999 21:07:14 +0200
Message-Id: <v04210120b3c62ee6883f@[130.237.150.138]>
To: IETF Applications Area Discussion List <discuss@apps.ietf.org>
Is the terminology below correct?

User agent (UA)     A module which communicates with a user through
                     a user interface, and performs network operations,
                     possibly connecting to one or more servers, to
                     satisfy user requests.

Service agent (SA)  An agent which performs services, either in the
                     background or at the request of User Agents.

Client              A process which opens connections to servers,
                     and gives commands to them and gets the results.

Server              A process which accepts connections from clients
                     and either accepts and performs them, or refuses them.

Important in the terminology above is the distinction between
"client" and "user agent". User agents are usually clients, but all
clients are not user agents.

If this is the right terminology, what is then the correct word
for an HTTP server which provides interactive services using
HTML forms? From an HTTP viewpoint, such a server is a server
and not a client. But from an application viewpoint, it is a
user agent. So a user agent can be a server.
------------------------------------------------------------------------
Jacob Palme <jpalme@dsv.su.se> (Stockholm University and KTH)
for more info see URL: http://www.dsv.su.se/~jpalme
Received on Thursday, 29 July 1999 15:06:42 GMT

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