DOS and DDoS Simulation +Comparison and Analysis of Xgraph

That is the very basic way of simulating DoS attack in a ns2 simulation.

If you run the simulation, it may create a trace file. For example, the following lines will open the file TCP_Name-out.tr and write all trace events in it.

set TraceFD [open $TCP_Name-out.tr w]

$ns trace-all $TraceFD

After running the simulation, you may use a suitable scripting language like awk, perl etc., etc., to analyze the trace file. Or simply you may use shell scripts to do trace analysis. Search Internet you may find lot of such awk and perl files for trace analyzing the ns2 trace file.

You may learn about trace analysis from the following tutorials.

1. The Famous ns2 Tutorial by Marc Greis http://www.isi.edu/nsnam/ns/tutorial/
2. NS by Example by Jae Chung and Mark Claypool http://nile.wpi.edu/NS/