Welcome to LQ. ..
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Well, you could open a terminal window, and type :
sudo apt-get update && sudo apt-get install ns2
... and watch, if any error messages appear.
Note : The version you get from Ubuntu, is "2.35"
http://packages.ubuntu.com/precise/ns2
If you want to use ns-2.35, you'd probably also need 'ns2-examples'
http://packages.ubuntu.com/precise/ns2-examples
>
http://packages.ubuntu.com/precise/a...mples/filelist
Note 2. Also important : The package 'nam'.
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