  Simulators are the most dominant and eminent tool for analyzing and
investigating different type of networks. The simulations can be executed with
less cost as compared to large scale experiment as less computational resources
are required and if the simulation model is carefully designed then it can be
more practical than any well brought-up mathematical model. Generally P2P
research is based on the principle of simulate first and then experiment in the
real world and there is no reason that simulation results cannot be
reproducible. A lack of standard documentation makes verification of results
harder as well as due to such poor documentation implementation of well-known
overlay algorithms was very difficult. This Paper describes different types of
existing P2P simulators as well as provides a survey and comparison of existing
P2P simulators and extracting the best simulator among them.
