MAC/PHY Layer testbed

Hi im in the beginning of my masters thesis and im planning on
developing a
MAC/PHY layer testbed with gnuradio and how it can affect perfomance
etc. ,
i have seen other thesis:es about it (Naveen Manicka, 2007). And
searched
the mailing list about it, ive however only found discussions that it
is
about to be implemented but not yet done.

Am i better off starting from scratch for implementing MAC layer
functionality or should i checkout the work in progress and if, how do
i? Or
is the work done, ive just missed it somehow?