162 lines
4.1 KiB
HTML
162 lines
4.1 KiB
HTML
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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
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"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
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<!-- ABP.html (C) K. J. Turner 18/12/14 -->
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<html xmlns="http://www.w3.org/1999/xhtml">
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<head>
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<title>Alternating Bit Protocol</title>
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<link rev="made" href="http://www.cs.stir.ac.uk/~kjt/"/>
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<script type="text/javascript" language="JavaScript">
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<!--
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var simulator;
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var mediumType;
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var mediumTypeOld;
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function set() {
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mediumType =
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document.settings.medium[0].checked
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? 2
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: document.settings.medium[1].checked
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? 1
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: 0;
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if (mediumType != mediumTypeOld) {
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mediumTypeOld = mediumType;
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simulator.setParameter("mediumType", mediumType);
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simulator.restart();
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}
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}
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//-->
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</script>
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</head>
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<body background="simulator.jpeg"
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onload="simulator=document.ProtocolSimulator; set();">
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<div style="text-align: center">
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<h1>Alternating Bit Protocol Simulator</h1>
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<img src="simulator.gif" alt="Simulator Logo"/>
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</div>
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<h2>Protocol Description</h2>
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<p>
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ABP (Alternating Bit Protocol) is a connection-less protocol for
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transferring messages in one direction between a pair of protocol
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entities. It is a simple form of the <a href="SWP3.html">Sliding Window
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Protocol</a> with a window size of 1. The message sequence numbers simply
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alternate between 0 and 1.
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</p>
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<h2>Protocol Parameters</h2>
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<p>
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The following settings are adequate for a simple simulation. For a more
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advanced exploration, choose different options and click <em>Change
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Settings</em>. This will cause the simulation to restart.
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</p>
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<p>
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Optionally set the level of control that the simulator user needs over
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the medium:
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</p>
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<dl>
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<dt><b>Automatic</b>:</dt>
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<dd>
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Messages are delivered immediately without loss. This is suitable for
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initial experimentation, but limits what can be explored. For example,
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message are never lost and never have to be timed out and resent.
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</dd>
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<dt><b>Delivery</b>:</dt>
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<dd>
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Alternatively, message delivery may be controlled - though messages
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will still never be lost. Choose this option to allow messages to be
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delivered in different orders and to be resent.
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</dd>
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<dt><b>Delivery/Loss</b>:</dt>
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<dd>
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Finally, delivery and loss of messages may be completely controlled.
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This is the most comprehensive option, but also the most complex one to
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manage.
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</dd>
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</dl>
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<form name="settings">
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<center>
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<table cellpadding="5">
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<tr>
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<td align="right">Medium Control:</td>
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<td>
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<input type="radio" name="medium" value="2"
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checked="checked"/>Automatic
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</td>
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<td><input type="radio" name="medium" value="1"/>Delivery</td>
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<td><input type="radio" name="medium" value="0"/>Delivery/Loss</td>
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</tr>
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<tr>
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<td align="center" colspan="4">
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<input type="button" name="btnSet" value="Change Settings"
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onclick="set()"/>
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</td>
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<td colspan="3"></td>
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</tr>
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</table>
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</center>
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</form>
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<h2>Protocol Simulation</h2>
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<p>
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The protocol simulation shows a time-sequence diagram with transmitting
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and receiving protocol entities, and a communications medium that carries
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messages. The transmitter simply sends messages numbered <em>DATA(0)</em>
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or <em>DATA(1)</em>; the content of messages is not identified. These are
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acknowledged with <em>ACK(1)</em> or <em>ACK(0)</em> respectively. Note
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that if a <em>DATA</em> message is received again due to re-transmission,
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it is acknowledged but discarded.
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</p>
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<center>
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<applet code="simulator.ProtocolSimulator.class"
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archive="ProtocolSimulator.jar" width="600" height="700"
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name="ProtocolSimulator">
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<param name="protocol" value="ABP"/>
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</applet>
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</center>
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<hr/>
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<p>
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<a href="index.html"><img src="uparrow.gif" alt="Up Arrow"/></a>
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||
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Up one level to <a href="index.html">Protocol Simulators</a>
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||
|
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</p>
|
||
|
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|
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|
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</body>
|
||
|
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</html>
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