Abstract: To describe the approach of real-world activities we have proposed an idea by using ACO technique for providing security to the building and building can be bank, parliament house, prime minister house, ambani house etc. In this paper we are providing the security to the building and if any security-guard feels weakness than he can be replaced by other. And if there is the need of increase in the number of security-guards, they can do so on their own without interrupting the simulation and changing the input parameters.