Connectivity is the premise and foundation of networking and routing.For the probabilistic flight path of military aircraft resulting in the difficulty of Aeronautical Ad hoc NETwork(AANET) research,an estimation meth...Connectivity is the premise and foundation of networking and routing.For the probabilistic flight path of military aircraft resulting in the difficulty of Aeronautical Ad hoc NETwork(AANET) research,an estimation method of connectivity probability is proposed.The method takes airspace as the research object,starts with actual flight characteristics,and applies conclusions of random waypoint mobility model.Building a connectivity model by establishing Airspace Unit Circle(AUC) from the perspective of circle-circle coverage,the method obtains a theory of airspace network connectivity.Experiment demonstrates its correctness.Finally,according to the actual condition simulation,relationship between the number of aircraft,communication radius,and the flight area under connectivity probabilities is achieved,results provide reference for creating a network that under certain aerial combat condition.展开更多
Relationships between application layer protocols in softswitch are explored in this paper.Two notions, i.e.protocol relationship and protocol grouping, are proposed, which are not clearly defined and even not paid mu...Relationships between application layer protocols in softswitch are explored in this paper.Two notions, i.e.protocol relationship and protocol grouping, are proposed, which are not clearly defined and even not paid much attention to before.On the basis of a well known protocol relationship named protocol conversion, three novel protocol relationships including protocol collaboration relationship, protocol cooperation relationship and protocol independent relationship are presented, so that protocol relationships are classified into four types.According to the functionality and purpose of each protocol, main protocols related to softswitch are divided into five groups.As to protocol conversion in softswitch, information flow trail(IFT) is utilized to facilitate problem solving.A decision rule for protocol conversion mode is proposed to guide how to choose between direct conversion and indirect conversion.A property of protocol relationships in softswitch is induced from all kinds of service scenarios of softswitch.This property summarizes protocol relationships within each protocol group or between two specific protocol groups.A merit of protocol grouping together with classification of protocol relationship is also presented.The effort of this paper pushes the protocol engineering to go ahead.展开更多
In this paper,an Adaptive-Weighted Time-Dimensional and Space-Dimensional(AWTDSD) data aggregation algorithm for a clustered sensor network is proposed for prolonging the lifetime of the network as well as improving t...In this paper,an Adaptive-Weighted Time-Dimensional and Space-Dimensional(AWTDSD) data aggregation algorithm for a clustered sensor network is proposed for prolonging the lifetime of the network as well as improving the accuracy of the data gathered in the network.AWTDSD contains three phases:(1) the time-dimensional aggregation phase for eliminating the data redundancy;(2) the adaptive-weighted aggregation phase for further aggregating the data as well as improving the accuracy of the aggregated data; and(3) the space-dimensional aggregation phase for reducing the size and the amount of the data transmission to the base station.AWTDSD utilizes the correlations between the sensed data for reducing the data transmission and increasing the data accuracy as well.Experimental result shows that AWTDSD can not only save almost a half of the total energy consumption but also greatly increase the accuracy of the data monitored by the sensors in the clustered network.展开更多
To solve the problems of high memory occupation, low connectivity and poor resiliency against node capture, which existing in the random key pre-distribution techniques while applying to the large scale Wireless Senso...To solve the problems of high memory occupation, low connectivity and poor resiliency against node capture, which existing in the random key pre-distribution techniques while applying to the large scale Wireless Sensor Networks （WSNs）, an Identity-Based Key Agreement Scheme （IBKAS） is proposed based on identity-based encryption and Elliptic Curve Diffie-Hellman （ECDH）. IBKAS can resist man-in-the-middle attacks and node-capture attacks through encrypting the key agreement parameters using identity-based encryption. Theoretical analysis indicates that comparing to the random key pre-distribution techniques, IBKAS achieves significant improvement in key connectivity, communication overhead, memory occupation, and security strength, and also enables efficient secure rekcying and network expansion. Furthermore, we implement IBKAS for TinyOS-2.1.2 based on the MICA2 motes, and the experiment results demonstrate that IBKAS is feasible for infrequent key distribution and rekeying for large scale sensor networks.展开更多
文摘Connectivity is the premise and foundation of networking and routing.For the probabilistic flight path of military aircraft resulting in the difficulty of Aeronautical Ad hoc NETwork(AANET) research,an estimation method of connectivity probability is proposed.The method takes airspace as the research object,starts with actual flight characteristics,and applies conclusions of random waypoint mobility model.Building a connectivity model by establishing Airspace Unit Circle(AUC) from the perspective of circle-circle coverage,the method obtains a theory of airspace network connectivity.Experiment demonstrates its correctness.Finally,according to the actual condition simulation,relationship between the number of aircraft,communication radius,and the flight area under connectivity probabilities is achieved,results provide reference for creating a network that under certain aerial combat condition.
基金National Science Fund for Distinguished Young Scholars (No. 60525110)National 973 Program (No. 2007CB307100, 2007CB307103)+1 种基金National Natural Science Foundation of China (No. 60902051)Development Fund Project for Electronic and Information Industry (Mobile Service and Application System Based on 3G)
文摘Relationships between application layer protocols in softswitch are explored in this paper.Two notions, i.e.protocol relationship and protocol grouping, are proposed, which are not clearly defined and even not paid much attention to before.On the basis of a well known protocol relationship named protocol conversion, three novel protocol relationships including protocol collaboration relationship, protocol cooperation relationship and protocol independent relationship are presented, so that protocol relationships are classified into four types.According to the functionality and purpose of each protocol, main protocols related to softswitch are divided into five groups.As to protocol conversion in softswitch, information flow trail(IFT) is utilized to facilitate problem solving.A decision rule for protocol conversion mode is proposed to guide how to choose between direct conversion and indirect conversion.A property of protocol relationships in softswitch is induced from all kinds of service scenarios of softswitch.This property summarizes protocol relationships within each protocol group or between two specific protocol groups.A merit of protocol grouping together with classification of protocol relationship is also presented.The effort of this paper pushes the protocol engineering to go ahead.
基金Supported by the Promotive Research Fund for Excellent Young and Middle-aged Scientists of Shandong Province(No.BS2010DX010)the Project of Higher Educational Science and Technology Program of Shandong Province(No.J12LN36)
文摘In this paper,an Adaptive-Weighted Time-Dimensional and Space-Dimensional(AWTDSD) data aggregation algorithm for a clustered sensor network is proposed for prolonging the lifetime of the network as well as improving the accuracy of the data gathered in the network.AWTDSD contains three phases:(1) the time-dimensional aggregation phase for eliminating the data redundancy;(2) the adaptive-weighted aggregation phase for further aggregating the data as well as improving the accuracy of the aggregated data; and(3) the space-dimensional aggregation phase for reducing the size and the amount of the data transmission to the base station.AWTDSD utilizes the correlations between the sensed data for reducing the data transmission and increasing the data accuracy as well.Experimental result shows that AWTDSD can not only save almost a half of the total energy consumption but also greatly increase the accuracy of the data monitored by the sensors in the clustered network.
基金Supported by the National Basic Research Program of China(973 Program)(No.2011CB302903)the National Natural Science Foundation of China(No.61100213)+3 种基金the Key Program of Natural Science for Universities of Jiangsu Province(No.10KJA510035)the Specialized Research Fund for the Doctoral Program of Higher Education(20113223120007)the Science and Technology Program of Nanjing(201103003)the Postgraduate Innovation Project Foundation of Jiangsu Province(No.CXLX11_0411)
文摘To solve the problems of high memory occupation, low connectivity and poor resiliency against node capture, which existing in the random key pre-distribution techniques while applying to the large scale Wireless Sensor Networks （WSNs）, an Identity-Based Key Agreement Scheme （IBKAS） is proposed based on identity-based encryption and Elliptic Curve Diffie-Hellman （ECDH）. IBKAS can resist man-in-the-middle attacks and node-capture attacks through encrypting the key agreement parameters using identity-based encryption. Theoretical analysis indicates that comparing to the random key pre-distribution techniques, IBKAS achieves significant improvement in key connectivity, communication overhead, memory occupation, and security strength, and also enables efficient secure rekcying and network expansion. Furthermore, we implement IBKAS for TinyOS-2.1.2 based on the MICA2 motes, and the experiment results demonstrate that IBKAS is feasible for infrequent key distribution and rekeying for large scale sensor networks.
