Hi all,
I am a student research i have a project about qos aware mac protocol for wban i have run my project using ns3 but i still stack how to calculate end to end delay throughput i have generate the file .tr and the .pcap file using wireshark but i dont succeed to extract data to mesure end to end delay get the start time end time .
thanks .
Suppose we run a simulation ,and obtain a trace file “out.tr”. We would like to compute the average values of delay. Let’s define delay as the duration since a packet enters a queue of a beginning node until it it arrives at the ending node. The definition of beginning and ending nodes depends on the type of delay under consideration as follows:
Average delay is computed by :
E(delay)= summation of all delay samples/ no. of samples
where a delay sample is delay associated with a packet.
The key to collect delay sample is to record packet arrival time in an associative array variable, namely t_arr whose index is the packet unique ID.
When a new packet enters a queue of a beginning node, the associated time is recorded in a variable $t_arr[pid], where pid is the packet unique ID.
When a packet with the same unique ID arrives at an ending node, the delay is computed as “(current time) - $t_arr[pid]”.
The delay same is accumulated in the variable $total_delay, and the number of samles is incremented by one.
At the end of the program, the average delay is computed and stored in a variable avg_delay.
A sample execution of the AWK script is shown below:
============ abb.awk =========
BEGIN {
fromNode=2; toNode=3;
num_samples = 0;
total_delay = 0;
}
/^\+/&&$3==fromNode&&$4==toNode {
t_arr[$12] = $2;
};
/^r/&&$3==fromNode&&$4==toNode {
if (t_arr[$12] > 0) {
num_samples++;
delay = $2 - t_arr[$12];
total_delay += delay;
};
};
END{
avg_delay = total_delay/num_samples;
print "Average queuing transmission delay is " avg_delay " seconds";
print "Measurement details:";
print " - Start when packets enter the node " fromNode;
print " - Until the packets arrive the node " toNode;
};
============ abbfile.awk =========
BEGIN {
src="0.0"; dst="3.0";
num_samples = 0;
total_delay = 0;
}
/^\+/&&$9==src&&$10==dst {
t_arr[$12] = $2;
};
/^r/&&$9==src&&$10==dst{
if (t_arr[$12] > 0) {
num_samples++;
delay = $2 - t_arr[$12];
total_delay += delay;
};
};
END{
avg_delay = total_delay/num_samples;
print "Average end-to-end transmission delay is " avg_delay " seconds";
print "Measurement details:";
print " - Since packets are created from the address " src;
print " - Until the packets are destroyed at the address " dst;
};
Kindly check the following lo=inke which will surely you.
http://slogix.in/how-to-calculate-end-to-end-delay-for-wired-network-using-awk-script-in-ns2
Hi
At first, Note that u must measure not calculate.
See this link
http://ns2ultimate.tumblr.com/post/5240359082/post-processing-ns2-result-using-ns2-trace-ex3
Best Regards
Kindly check the following link
http://mohittahiliani.blogspot.com/2010/08/xgraph-and-awk-scripts-in-ns-2_06.html dly check the following lo=inke
You can use the classe reference FlowMonitor. You find it on the documentation of ns3 www.nsnam.org
You must define in your simulation the time where you send packets and when these packets are received. the difference for each packet is called the time delay end to end related to this packet. Obviously, you will send a huge number of packets so, here you must create a script to calculate the mean time delay for all the packets. Repeat this operation a number of times to get a more realistic results
But we must ignore packets that are dropped (not received at destination) due any reason, so i think we need to decrement sample count on every drop.
Delay is the difference between the time at which the sender generated the packet and the time at which the receiver received the packet
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