implementing a handoff algorithm in NS2
 

Hi everybody
I'm new in LinuxQuestion.org and this is my first question so I hope I'm posting in the right place !
Actually, I'm newbie in NS2. I already installed NS2.29.2 with Nist!
My project consists on implementing the algorithm of the Vertical Handover Decision of "Xia et al.’s VHD heuristic".

So as I understand:
1- I should prepare a simulation scenario in which a Mobile Node is crossing an heterogeneous wireless networks (Wimax and UMTS, may be Wifi : they are all installed with NIST) --> this file should be a .tcl one
Firstly, am I on the right track ???

2- Secondly, I should implement the algorithm of Decision, how the mobile node decide to hand-off from a network to another !!
So my question is, this algorithm should be written in .tcl format or .h (in C++) ???
If it's in C++, how can I make the relation between the scenario and the algorithm ???

Can you explain to me pleaaaaaaaaaaaaaaaaaaase, I'm stuck
thanks in advance]

Moved at OP's request.