2003-08-07 14:30:41 +04:00
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.\" $NetBSD: 3.t,v 1.3 2003/08/07 10:30:55 agc Exp $
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1998-01-09 09:54:57 +03:00
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.\"
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1994-06-19 04:07:16 +04:00
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.\" Copyright (c) 1983, 1986, 1993
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.\" The Regents of the University of California. All rights reserved.
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.\"
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.\" Redistribution and use in source and binary forms, with or without
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.\" modification, are permitted provided that the following conditions
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.\" are met:
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.\" 1. Redistributions of source code must retain the above copyright
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.\" notice, this list of conditions and the following disclaimer.
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.\" 2. Redistributions in binary form must reproduce the above copyright
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.\" notice, this list of conditions and the following disclaimer in the
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.\" documentation and/or other materials provided with the distribution.
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2003-08-07 14:30:41 +04:00
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.\" 3. Neither the name of the University nor the names of its contributors
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1994-06-19 04:07:16 +04:00
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.\" may be used to endorse or promote products derived from this software
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.\" without specific prior written permission.
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.\"
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.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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.\" SUCH DAMAGE.
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.\"
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.\" @(#)3.t 8.1 (Berkeley) 6/8/93
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.\"
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.nr H2 1
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.\".ds RH Goals
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.br
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.ne 2i
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.NH
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\s+2Goals\s0
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.PP
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The networking system was designed with the goal of supporting
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multiple \fIprotocol families\fP and addressing styles. This required
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information to be ``hidden'' in common data structures which
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could be manipulated by all the pieces of the system, but which
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required interpretation only by the protocols which ``controlled''
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it. The system described here attempts to minimize
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the use of shared data structures to those kept by a suite of
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protocols (a \fIprotocol family\fP), and those used for rendezvous
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between ``synchronous'' and ``asynchronous'' portions of the
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system (e.g. queues of data packets are filled at interrupt
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time and emptied based on user requests).
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.PP
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A major goal of the system was to provide a framework within
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which new protocols and hardware could be easily be supported.
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To this end, a great deal of effort has been extended to
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create utility routines which hide many of the more
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complex and/or hardware dependent chores of networking.
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Later sections describe the utility routines and the underlying
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data structures they manipulate.
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