📄 queuemon.html
字号:
<html>
<head>
<title>RED Queue Monitor Example</title>
</head>
<body background="parchment.gif" tppabs="http://nile.wpi.edu/NS/Icons/parchment.gif" text="#000000" link="#0000FF"
vlink="#000080" alink="#FF0000">
<br>
<center><h2>RED Queue Monitor Example</h2></center>
<br><br>
<dl>
<p>This section shows a RED queue monitoring example. Example 5 is an OTcl script written by <a href="javascript:if(confirm('http://www.tik.ee.ethz.ch/~huang/ \n\nThis file was not retrieved by Teleport Pro, because it is addressed on a domain or path outside the boundaries set for its Starting Address. \n\nDo you want to open it from the server?'))window.location='http://www.tik.ee.ethz.ch/~huang/'" tppabs="http://www.tik.ee.ethz.ch/~huang/" target=_top>Polly Huang</a>, which sets up the network topology and runs the simulation scenario shown in Figure 15. Note that a RED queue that can hold up to 25 packets is used for the link r1-r2, and we want to see how the RED queue works by measuring the dynamics of current and average queue size. To run this script, download "<a href="red.tcl" tppabs="http://nile.wpi.edu/NS/Example/red.tcl">red.tcl</a>" and type "<font color=GREEN>ns red.tcl</font>" at your shell prompt. </p>
<p align="center"><img src="fig15.gif" tppabs="http://nile.wpi.edu/NS/Figure/fig15.gif"><br><br>
<b>Figure 15.</b> RED Queue Monitor Example Setup</p>
<p align="center">
<a href="red.tcl" tppabs="http://nile.wpi.edu/NS/Example/red.tcl"><img src="ex5.gif" tppabs="http://nile.wpi.edu/NS/Figure/ex5.gif" border=1 alt="red.tcl"></a><br><br>
<b>Example 5.</b> RED Queue Monitor Simulation Script
</p>
<p>There are couple of things to note in the above script. First, more advanced Simulator object member function <font color=GREEN>create-connection</font> is used to create TCP connections. Second, take a good look at queue tracing (monitoring) part of the script. These lines make a variable to point the RED queue object, call its member function <font color=GREEN>trace</font> to monitor the current queue size (<font color=GREEN>curq_</font>) and average queue size (<font color=GREEN>avg_</font>), and make them write the results to the file "<font color=RED>all.q</font>". Following are the two queue trace output formats for average queue size and current queue size.</p>
<table align=CENTER cellpadding=0 cellspacing=0><tr><td>
<font size=-1 face="Courier New">
a time avg_q_size<br>
Q time crnt_q_size
</font>
</td></tr></table>
<p>Now that the all commands needed for RED queue monitoring is done except closing the "<font color=RED>all.q</font>" file when the simulation is done, the remaining work designs a post-simulation process. This script, using <a href=" javascript:if(confirm('http://www.canberra.edu.au/~sam/whp/awk-guide.html \n\nThis file was not retrieved by Teleport Pro, because it is addressed on a domain or path outside the boundaries set for its Starting Address. \n\nDo you want to open it from the server?'))window.location='http://www.canberra.edu.au/~sam/whp/awk-guide.html'" tppabs="http://www.canberra.edu.au/~sam/whp/awk-guide.html" target=_top>awk</a>, does this process of transforming the monitored information into <a href=" javascript:if(confirm('http://jean-luc.ncsa.uiuc.edu/Codes/xgraph \n\nThis file was not retrieved by Teleport Pro, because it is addressed on a domain or path outside the boundaries set for its Starting Address. \n\nDo you want to open it from the server?'))window.location='http://jean-luc.ncsa.uiuc.edu/Codes/xgraph'" tppabs="http://jean-luc.ncsa.uiuc.edu/Codes/xgraph" target=_top>XGraph</a> (a plotter) input format, and launches it to draw the given information (see Figure 16). </p>
<p align="center"><img src="fig16.gif" tppabs="http://nile.wpi.edu/NS/Figure/fig16.gif" border=1><br><br>
<b>Figure 16.</b> Red Queue Trace Graph</p>
</dl>
</body>
</html>
⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -