04-10-2016, 09:21 AM
• In order to be able to use ns2, you first have to do the following
– Type in your shell
source /p/edu/s-38.180/usens2.csh
– This file contains the required settings for environment variables
– Give this command each time you start an ns2 session in a shell
• After that you can use ns2 simply by writing in your shell
ns my_script.tcl
• Top directory where ns2 source files are is:
– /p/edu/s-38.180/src/ns-2.1b9a_standard/
• Provides reliable file transfer over Internet
• Includes functionality for congestion control
– contains many sophisticated algorithms for realizing congestion control
– Basic idea: increase rate slowly, but decrease quickly when facing congestion
– Congestion detected from packet losses (i.e., TCP only reacts to losses)
– Example of ideal TCP rate behavior shown below