6.829 ns Simulator Information (Fall 2000)
ns on Athena
Running ns.
We have installed a version of the ns simulator onto Athena for your convenience.
To run the simulator, you first need to add the 6.829 course locker to
your execution path. To do this, type the following command at your athena
prompt: add 6.829. For the rest of your login session, you can
run ns by simply typing ns at your shell prompt. The simulator
is currently only available for Athena Linux workstatations. If you do not
have access to Athena, you can build your own copy of the ns simulator
from source by downloading it from the official
ns website.
Note: You will run into trouble running ns if your UNIX
$PATH environment variable lists another directory before the 6.829
locker that contains an ns binary. For example, the sipbnet
locker, which many of you may have added to your path to access the
"tcpdump" utility, also contains a binary for ns. This
version of ns is not supported by 6.829. You should make sure that
the 6.829 locker appears before the sipbnet locker in your UNIX path.
Moreover, ns in the 6.829 locker has been compiled on linux
platform in athena. So, you may need to find a Linux machine in athena
to run ns.
Accessing the source code.
You can find all of the source code for ns, as well as other useful course
materials, in the course locker. Once you have typed add 6.829
at your athena prompt, you can find the code in the following directory:
/mit/6.829/software/ns-allinone-2.1b8a/
Modifying the source code.
If you wish to modify the ns source code, you have two options. You can
either copy the entire distribution into your home directory from the course
locker (110 MB), or you can create soft links to the course locker in your
own directory. Using this second option, you can modify the source code
by copying those files that you wish to modify into your directory. The
advantage of this approach is that you will avoid using up your athena
disk quota with a 110Mb copy of the ns source distribution. If you do not
know how to make soft links, we have written a script for you to automate
the process:
-
Add the course locker to your path by typing add 6.829 at your
athena prompt.
-
Create an area in your home directory for your private copy of the ns source
code, for instance: /mit/joeuser/ns-2.
-
Change to your new directory: cd /mit/joeuser/ns-2.
-
Create the links:
make_nslinks. This command will copy some files
into your own directory and create soft links to the ns source code.
-
In order to make a new version
of the simulator, you will need to first type add
gnu at your athena prompt. This will put all of the necessary
gnu compilers and software into your path.
Whenever you wish to modify a file, you should copy the file from the course
locker into your home directory.
Useful ns links
If you find other interesting or useful sites related to ns, please send
mail to bansal@lcs.mit.edu he
will add them to this page.
Last update: Fri
Sep 6 9:30:08 EDT 1999 (bansal)