| The rapid development of computing technology leads the correspondinginnovation of computing method. At present, the computing technology has been indesktop computing for several decades, and pervasive computing technology isbecoming the development direction of future computing.Pervasive computing extends the boundary of computing. People can accesstransparently services at anytime and anywhere. The computer itself will disappearfrom people’s sight, and physical space and information space will emerge into awhole one. People will just focus on the tasks to be completed. In the case ofpervasive computing, environment will be invisible. This kind of mode bringsconvenience to people. Meanwhile, people can’t control the computing mode and theflow of resources. Pervasive computing environment presents a formidable challengeto the traditional security mechanisms. Traditional security authentication methodscannot be directly applied to the pervasive computing environment. With thedevelopment of research on pervasive computing, the security problem also becomesan important problem urgent to be solved.Many researchers at home and abroad dedicated to solve this problem from allaspects. From the perspective of trust and certification, the solutions are modificationsof mature traditional security authentication scheme, also the uses of a new dynamictrust management models. The traditional safety certification is mature, and has beenapplied. However its binary outcomes are not flexible. A dynamic trust managementmodel can satisfy the needs of pervasive environment, but still has not mature modeland evaluation standard.This paper proposes a trust computation model incorporates the traditional safetyauthentication technology with trust management model, and introduces agent entitiesbetween the pervasive environment entity and the service entities. Agent entitychooses different authentication methods for different types of users, and choosesservice entity for user request.This paper accomplishes a framework of this model. According to the needs ofthe framework, an authentication protocol and a dynamic trust model are proposed.The formal analysis is conducted on the safety protocol, and simulation of the trustmodel is completed. The authentication is designed by improving a three party’s keychanging protocol Otway-Rees. It is proved that the protocol can satisfy thecertification requirements and security requirements. In the simulation of trust model,a trust management model PTM is improved. The trust management for serviceentities was enhanced with agent entities. The netlogo is used to simulate the model.The simulating results show that the proposed model is excellent in success rate ofinteraction when it is compared to the PTM model and the model with no agent. |
