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Kademlia is a famous routing algorithm based on DHT in P2P network research. To conquer the shortages of Kademlia in searching efficiency and the strategy of cache, an improved Kademlia routing algorithm is proposed which can accelerate the hotspots inquiry speed in P2P network and is implemented by using fast table look-up and weights setting method. This technique avoids inefficient inquiry under the high refreshing frequency in cache and congregates hotspot resources for high query hit rate. Simulation tests show that the improved algorithm has lower average route step and inquiry time delay than the original one.

MPI is the most important parallel programming tool in cluster currently. It implements communication in parallel program by message. Implementing load balance in MPI parallel program is very important. It may reduce running time and improve performance of MPI parallel program, aiming at solving the dynamic balancing problem in homogeneous cluster system. This paper proposes an implementing method in MPI parallel program that can transfer tasks between nodes effectively by node’s load. The experiments prove the availability and practicability of the algorithm in parallel computing task.

Due to the unknown Web attacks are hardly be detected and the early warning and response mechanism cannot be established, many of intrusion detection systems (IDSs) are only effective in detecting known Web attacks and cannot evaluate the risk of Web service. In order to conquer these limitations and inspired by immune principles, this paper presents an immune-based active defense model for Web attacks which is on the basis of the clone selection and hyper-mutation. Therefore, the immune learning algorithm and the attack detection mechanism are given. The risk of Web attacks is quantitatively analyzed on the relationship between the antibody concentration and the state of an illness in biological immune system (BIS). Theoretical analysis and experimental evaluation demonstrate that the model is more suitable for detecting unknown attacks, and provides an active defense mechanism for detecting network anomalies.