- There are two types of models useful in the study of worm propagation for a given number of terminals in a trusted network i.e. deterministic and stochastic model. The deterministic models, also known as compartmental models are in the form of epidemic models. These epidemic models consist of different states called compartments so these models are also known as compartmental models. A closed (no inflow and outflow) donor control based compartmental model can be converted in to the stochastic model which is more realistic and also enables us to compute the transition probability from one state to other state. In this paper authors have presented a method for stochastic modeling of worm or virus propagation in trusted networks.