Current quality of service（QoS） routing schemes for low earth orbit（LEO） satellites IP networks either neglect the varying population density or fail to guarantee end-to-end delay.As a remedy,QoS routing protocol based on mobile agent（QoSRP-MA） is proposed.QoSRP-MA is a source-based routing protocol.Once connection requests arrive,QoS mobile agents are dispatched from ingress satellite to explore routes,which migrate using satellite routing tables.Upon arriving in egress satellite,QoS mobile agents migrate back towards ingress satellite to reserve bandwidth.To construct satellite routing tables,load balancing routing algorithm based on mobile agent（LBRA-MA） is presented.In LBRP-MA,at regular intervals mobile agents launched on all satellites migrate autonomously to evaluate path cost and update routing tables.Moreover,path cost between source and destination is evaluated considering satellite geographical position as well as inter-satellite link（ISL） cost.Furthermore,ISL congestion index is considered to update routing table.Through simulations on a Courier-like constellation,it shows that QoSRP-MA can achieve guaranteed end-to-end delay bound with higher throughput,lower connection failing ratio and signaling overhead compared to high performance satellite routing（HPSR） scheme.
RAO Yuan,WANG Ru-chuan College of Computer,Nanjing University of Posts and Telecommunications,Nanjing 230001,China
In this paper, a clustering algorithm is proposed based on the high correlation among the overlapped field of views for the wireless multimedia sensor networks. Firstly, by calculating the area of the overlapped field of views （FoVs） based on the gird method, node correlations have been obtained. Then, the algorithm utilizes the node correlations to partition the network region in which there are high correlation multimedia sensor nodes. Meanwhile, in order to minimize the energy consumption for transmitting images, the strategy of the cluster heads election is proposed based on the cost estimation, which consists of signal strength and residual energy as well as the node correlation. Simulation results show that the proposed algorithm can balance the energy consumption and extend the network lifetime effectively.
This article is focused on analyzing the key technologies of new malicious code and corresponding defensive measures in the large-scale communication networks. Based on description of the concepts and development of the malicious code, the article introduces the anti-analysis technology, splitting and inserting technology, hiding technology, polymorph virus technology, and auto production technology of the malicious code trends with intelligence, diversity and integration. Following that, it summarizes the security vulnerabilities of communication networks from four related layers aspects, according to the mechanisms of malicious code in the communication networks. Finally, it proposes rapid response disposition of malicious code attacks from four correlated steps： building up the network node monitoring system, suspicious code feature automation analysis and extraction, rapid active malicious code response technique for unknown malicious code, and malicious code attack immunity technique. As a result, it actively defenses against the unknown malicious code attacks and enhances the security performance of communication networks.
LI Peng,WANG Ru-chuan ,ZHANG Wei College of Computer,Nanjing University of Posts and Telecommunications,Nanjing 210003,China
In order to reduce makespan and storage consumption in data grids, a node selection model for replica creation is proposed. The model is based on the degree distribution of complex networks. We define two candidate replica nodes： a degree-based candidate pool and a frequency-based candidate pool, through which a degree-based candidate pool is defined in consideration of onsidering the access frequency; a candidate pool-based frequency is also defined. The data replica is copied to the node with the minimum Local cost in the two pools. Further, this paper presents and proves a replica creation theorem. A dynamic multi-replicas creation algorithm （DMRC） is also provided. Simulation results show that the proposed method may simultaneously reduce makespan and data used in space storage consumption.
CHEN Dan-wei ,ZHOU Shu-tao,REN Xun-yi,KONG Qiang College of Computer,Nanjing University of Posts and Telecommunications,Nanjing 210003,China
