Distributed Network Simulation Technology And Its Security Situation Application

Network simulation is an essential method of studying the network behavior, evaluating the network protocols and analyzing network algorithms. With the rapid development of computer networks, the size of topology scale for research is becoming larger, and the amount of computation time required to perform large-scale network simulation is prohibitive. How to reduce the simulation time and improve the performance of simulation? One effective way to solve this problem is to parallelize and distribute the simulation to a number of different machines, so that each machine can share a portion of the workload.How to use the computational resource of different machines to improve the simulation performance? How to assign the network simulation task reasonably to realize the load balance for all machines in the distributed network simulation environment? How to put the simulation theory into practical use? Those are main problems of distributed network simulation. So, more research on those problems will be needed.The research subject of this paper is based on distributed network simulation technology.This paper introduces the concepts and technologies of distributed network simulation,performance of network simulation and partition for network simulation task. Aiming at the existing problem, this paper is mainly composed of the following three parts:Firstly, to improve the network simulation performance in heterogeneous computing environment, evaluation model for performance of network simulation is introduced. The factors affecting network simulation task are analyzed, including synchronization overhead,remote communication overhead, routing simulation overhead, packet forwarding and simulation overhead. Afterwards, the methods of the corresponding analyses and tests will be proposed on its model influence factors. The experimental result indicates that the evaluation model can accurately estimate the performance of large-scale network simulation task in heterogeneous computing environment. There is an obvious decrease in the average error coefficient relative to the current evaluation model for performance.Secondly, to reduce the running time of network simulation in heterogeneous computing environment, a load balance method for network simulation task is put forward. Based on the given heterogeneous computing environments, this method can take account of the load balance of packet forwarding simulation task and routing computing simulation task.Experiments based on PDNS indicate that, the simulation running time of this method is reduced obviously. In addition, experimental analysis shows that the method is applicable for large-scale network simulation topology.Finally, to put the simulation theory into practical use, a model of network security situational assessment based on multilevel fuzzy comprehensive evaluation is put forward.The model takes the characteristics of multi-source information and complicated data structure into account in the network security research. This paper calls the model improved Analytic Hierarchy Process and Fuzzy Comprehensive Evaluation(AHP_FCE). The effectiveness of this method is evaluated using GTNets.