Research And Implementation On Topology Abstraction Algorithm For Parallel Network Simulation

Network simulation has become an important method to study Internet behavior, but due to the large size of Internet, the complexity and the other characteristics, parallel simulation of large-scale network has become an indispensable way to study network behavior. Parallel network simulation requires much more resources. One way to save simulation resources and shorten the running time is reducing the size of the simulation topology. The main idea of topology abstraction algorithms proposed in this paper is to reduce the size of simulation topology.First the paper studies mechanism of network simulation, analyzes the factors that affect the analog performance, then presents a strategy to reduce the consumption of resources, which is topolopy abstraction algorithm.Most of hosts have been abstracted in this high-performance large-scale network simulation system, only the hosts that are attacking hosts or being attacked are exist,for those hosts are related to security incidents. Security incidents are dynamic bound to those hosts, in this way the consumption of resources caused by the hosts are largely reduced. Topology abstraction algorithm presented in this paper is mainly for the router of simulation topology, and then write the results of the algorithm into a text file and into database.The paper presents three topological abstraction algorithm, they are line topological abstraction algorithm, star topological abstraction algorithm and topological abstraction algorithm based on important nodes and important edges. First the third algorithm detect the nodes of the topology, and cut the circle according to certain strategy, then recycles the line and the star topology abstraction algorithm to abstract topology, outputs the result. Topology abstraction algorithm presented in the paper is not an algorithm which simplely deletes nodes or edges of topology. In this algorithm nodes which are abstracted are stored in their own abstract nodes in a data struct. Receiving and sending packets in abstract nodes use the dynamic continuous calculation, which makes the system reduces the number of discrete events in running time.The experiment results show that the parallel network simulation system reduces memory consumption and shortens the execution time when using the topology abstraction technique which makes the parallel network simulation system capable of abstracting large-scale network. Those results show that the topology abstraction technique proposed in the paper has better performance.