Set class _ x set fid _ x

There are some explanations on the network of set class _ x and set fid _ x. When set class _ x is related to the color settings in nam, and set fid _ x is the ID of the network stream, which is irrelevant to the color. Tested in windows XP + cygwin + ns2.29, the priority of set fid _ x coloring in nam is higher than that of set class _ x. For more information, see the following example.# Create a simulator object <br/> set ns [new Simulator] </p> <p> # Define different colors for data flows (for NAM) <br/> $ ns color 1 Blue <br/> $ ns color 2 Red </p> <p> # Open the NAM trace file <br/> set nf [open out. nam w] <br/> $ ns namtrace-all $ nf </p> <p> # Define a 'finish 'procedure <br/> proc finish {}{ <br/> global ns nf <br/> $ ns flush-trace <br/> # Close the NAM trace file <br/> close $ nf <br/> # Execute NAM on the trace file <br/> exec nam out. nam & <br/> exit 0 <br/>}</p> <p> # Create four nodes <br/> set n0 [$ ns node] <br/> set n1 [$ ns node] <br/> set n2 [$ ns node] <br/> set n3 [$ ns node] </p> <p> # Create links between nodes <br/> $ ns duplex-link $ n0 $ n2 2 Mb 10 ms DropTail <br/> $ ns duplex-link $ n1 $ n2 2 Mb 10 ms DropTail <br/> $ ns duplex-link $ n2 $ n3 1.7 Mb 20 ms DropTail </p> <p> # Set Queue Size of link (n2-n3) to 10 <br/> $ ns queue-limit $ n2 $ n3 10 </p> <p> # Give node position (for NAM) <br/> $ ns duplex-link-op $ n0 $ n2 orient right-down <br/> $ ns duplex-link-op $ n1 $ n2 orient right-up <br /> $ ns duplex-link-op $ n2 $ n3 orient right </p> <p> # Monitor the queue for link (n2-n3 ). (for NAM) <br/> $ ns duplex-link-op $ n2 $ n3 queuePos 0.5 </p> <p> # Setup a TCP connection <br/> set tcp [new Agent/TCP] <br/> $ tcp set class _ 2 <br/> $ ns attach-agent $ n0 $ tcp <br/> set sink [new Agent/TCPSink] <br/> $ ns attach-agent $ n3 $ sink <br/> $ ns connect $ tcp $ sink <br/> $ tcp set fid _ 1 </p> <p> # Setup FTP over TCP connection <br/> set ftp [new Application/FTP] <br/> $ ftp attach-agent $ tcp <br/> $ ftp set type _ FTP </p> <p> # Setup a UDP connection <br/> set udp [new Agent/UDP] <br/> $ ns attach-agent $ n1 $ udp <br/> set null [new Agent/Null] <br/> $ ns attach-agent $ n3 $ null <br/> $ ns connect $ udp $ null <br/> $ udp set fid _ 2 </p> <p> # Setup a CBR over UDP connection <br/> set cbr [new Application/Traffic/CBR] <br/> $ cbr attach-agent $ udp <br/> $ cbr set type _ CBR <br/> $ cbr set packet_size _ 1000 <br/> $ cbr set rate _ 1 mb <br/> $ cbr set random _ false </p> <p> # Schedule events for the CBR and FTP agents <br/> $ ns at 0.1 "$ cbr start" <br/> $ ns at 1.0 "$ ftp start "<br/> $ ns at 4.0" $ ftp stop "<br/> $ ns at 4.5" $ cbr stop "</p> <p> # Detach tcp and sink agents (not really necessary) <br/> $ ns at 4.5 "$ ns detach-agent $ n0 $ tcp; $ ns detach-agent $ n3 $ sink "</p> <p> # Call the finish procedure after 5 seconds of simulation time <br/> $ ns at 5.0" finish "< /p> <p> # Print CBR packet size and interval <br/> puts "CBR packet size = [$ cbr set packet_size _]" <br/> puts "CBR interval = [$ cbr set interval _] "</p> <p> # Run the simulation <br/> $ ns run </p> <p>In this example, the color of the corresponding network stream in nam is changed as long as the 'X' value in set fid _ x is changed. The color of 'X' in set class _ x does not change. After the set fid _ x statement is commented out, change the 'X' value in set class _ x to the corresponding color value, and the color changes accordingly. Comment out set class _ x, and the color is black.