Re:

I am a student doing my Masters thesis. My query is that

Someone doing graduate studies in networking should really do some basic research before asking questions on a mailing list. Normally, you start by reviewing the literature. If you had done that you would have discovered that your questions don't have an answer because you are asking the wrong questions. You will also discover that the network operators on this mailing list don't have the kind of answers that you are looking for. I suggest that you spend a few weeks reading papers from http://citeseer.nj.nec.com/cs and also from the homepages of the authors. --Michael Dillon