A secure communication mechanism is necessary in the applications of Wireless Multimedia Sensor Networks (WMSNs), which is more vulnerable to security attacks due to the presence of multimedia data. Additionally, given the limited technological resources (in term of energy, computation, bandwidth, and storage) of sensor nodes, security and privacy policies have to be combined with energy-aware algorithms and distributed processing of multimedia contents in WMSNs. To solve these problems in this paper, an energy efficient distributed steganography scheme, which combines steganography technique with the concept of distributed computing, is proposed for secure communication in WMSNs. The simulation results show that the proposed method can achieve considerable energy efficiency while assuring the communication security simultaneously.
Anti-worm is an effective way to fight against malicious worm and has been followed closely by malicious worm researchers recently.However,active and passive confronting technologies in peer-to-peer (P2P) networks have not been studied in depth.This paper introduces both of them to fight against malicious worm in P2P networks.To study their effectiveness in P2P networks,this paper takes the topology degree in P2P networks into consideration and puts forward a four-state propagation model for active anti-worm and a five-state propagation model for passive anti-worm respectively.Both of the models are simplified in the case that size of a P2P network is large enough.The simulation results have not only validated the effectiveness of our propagation models but also evaluated the excellent performance of both active anti-worm and passive anti-worm.
The Wyner-Ziv distributed video coding scheme is characterized for its intraframe encoder and interframe decoder which can also approach the efficiency of an interframe encoder-decoder system. In Wyner-Ziv residual coding of video, the residual of a frame with respect to a reference frame is Wyner-Ziv encoded, which can reduces the input entropy and leads to a higher coding efficiency than directly encoding the original frame. In this paper, we propose a new approach of residual coding combined with Region Of Interest (ROI) extraction. Experimental results show that, the proposed scheme achieves better rate-distortion performance compared to conventional Wyner-Ziv coding scheme.
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.
