Network security has a very vital role in provisioning of accurate and reliable operation in wide distributed networks. The rapid evolution of interlinked network and the ever increasing volume of data exchange have resulted in raise on new threats of attacks and network vulnerability. Need of developing new approaches in security provision hence evolved as a challenging task in data exchange. This research focus on developing methods to overcome different attacks over a wide network using topology based security approach. Topology based approach use the deployment of nodes and links to model a graph and over it develop different approach of security provisions. In development of topology based method ¿attack graph¿ has been proposed and used in various real time applications. Attack graph developed as a graph model, is used in exploring paths, nodes or links for its vulnerability and developing resilient methods to counter the attacks. The pre estimation of network vulnerability results in improvement of different factors of network performance such as the attack resilience, accuracy, delay, network throughput etc.