Parallel Algorithm For Protocol Reassembling In Application Layer

Today when various kinds of network applications popularize day by day, along with the development of e-business, the security of the network is paid attention to unprecedentedly. Intrusion Detection System (IDS) captures and analyses all the packets through the network, finds potential attack, informs administrators or takes the protective measure by oneself according to the tactics that are made in advance. Because of the huge calculating amount produced in course of reassembling the IP fragments and TCP flows in the detection system, adopting parallel reassembling algorithm becomes a kind of feasible scheme. At present distributed computing technique offers the good environment for parallel computing.Combining the performance-based objective effectively, this paper achieves the deep and careful research work on three areas: intrusion detection system, parallel algorithms for email reassembling, and parallel partition strategy.Firstly, according to the weak point of the detection system, especially in the procedure of IP fragments and TCP flows reassembling, we introduce parallel computing into reassembling procedure and present the parallel reassembling algorithm in application layer.Secondly, this paper designs the system structure, designing thought and work environment of parallel reassembling algorithm. By theoretical analysis and experimental results, we can confirm the improvements provided by parallel reassembling algorithm.Finally, this paper presents optimized parallel reassembling algorithm based on the former algorithm and proofs its advantages. Furthermore, we put forward the dynamic partition strategy based on different TCP conversation chains, which fully utilizes the computing capability of each computer, and resolves the problem by parallel algorithm effectively, and directs the future research.