Wireless sensor networks are often deployed in open or even hostile environment, its security problem is very prominent, Data aggregation is easily to be attacked for security during the specific implementation process. In order to reduce the transmission of redundant data and enhance security, this article proposed a secure data aggregation and authentication scheme, .data was gathered according to the mode code, collection data was transmitted in encrypted form which will be selected nodes, ensured the confidentiality of the data; A session key was generated and delaied aggregation and authentication by using counter, ensured the integrity , authenticity and freshness of data during the transmission .The security analysis showed that the program had higher security which resisted the attack initiativly, node compromise attack and select forwarding attack and other malicious behaviors.

In this paper, we propose a context-awareness based personalized recommender system in the pervasive application space. The recommender system comprises the personalized recommender engine and the distributed context management framework. With a hybrid approach, the personalized recommender engine combines those contexts into the decisions on recommendations to get more comprehensive recommendation effectiveness. In contrast with existing middleware of context-awareness, the recommender system has an ability of user-centric recommendation. At the end of this paper, an emphasis is put on the metrics of the effectiveness of the recommender system.

This paper introduces the architecture of wireless sensor networks, compares several typical routing protocols of wireless sensor network, and focuses on the research of directed diffusion(DD) protocol and geograohic and energy aware routing(GEAR) protocol. GEAR selects the next hop nodes based on the neighbor node location information, limiting the information diffused in the network in the appropriate location of region, which can effectively reduce the maintaining routing information needed for overhead, and form the energy efficient data transmission path, to achieve the purpose of extending the life cycle of the network. Related research work provides the reference for the future network construction.

With the rapid development of computer technology and wireless network communication technology, video encoding technology will be more and more widely applied in the limited resources of the wireless network. Due to the large amount of data of the video transmission , transmission quality of transmit video on the wireless network are varied with different compression parameters, network parameters and network conditions. Simulation results show that the transmission of video over wireless networks, must be based on the current network conditions, choosing the suitable GOP length and quantitative parameters to get the high image quality. In specific applications, network topology, network bandwidth, routing technology and transmission of packet segmentation scheme and other factors will affect the quality of service for video services.

In order to solve the security issue about network intrusion in IPv6 system, two modes of intrusion detection system based on IPv6 protocol analysis have been developed and designed. Based on these two modes, packet capture module, protocol analysis module, command parsing module and out-put processing module have been designed. The accuracy and efficiency of intrusion detection system based on IPv6 protocol analysis have been verified through the test focused on the key modules.