Problem encountered while downloading

[Mr Kashinath Basu <kbasu@dsrg.brookes.ac.uk>]

Dear Sir,

I am a PhD student working on the area of multicasting. Presently, I am
planning to do some multicast simulations using ns. Although I have
successfully downloaded TCL/TK and OTCL from the Berkeley site, but I
was unable to successfully download ns. When I downloaded the file from
the ns site(http://www-mash.cs.berkeley.edu/ns/ns-build.html), I found
it was a Log of ns-change history and not the ns software. I tried it
repeatedly, but everytime it was the same file. 

I will be very grateful if you can kindly explain me how to extract ns
from this file.

With regards,
Kashinath