Optimal Control of Treatment Costs for Internet Worm

There has been a constant barrage of worms over the internet during the recent past. Besides threatening network security, these worms cause an enormous economic burden in terms of loss of productivity at the victim hosts. In addition, these worms create unnecessary network delay incurred by both infection and treatment which is the level of filtering. To develop appropriate tools for thwarting quick spread of worms, researchers are trying to understand the behavior of the worm propagation with the aid of epidemiological models. In this study, we have presented an optimization model that takes into account the infection and treatment costs. Using this model we can determine the level of treatment to be applied for a given rate of infection spread. The simulation study also shows the optimal level of treatment which should be chosen to minimize the total cost of infection and to reduce the current infection rate. This information could be usefully employed to choose hosts for quarantine to reduce the prospects of the spread of infection in the future. 1