A Novel Trust Community Based on Direct Certifying for Pervasive Computing Systems

In the vision of pervasive computing, there are a great diversity of services in the environment and a great deal of nomadic users walking through them. The traditional proof-making mechanisms of access control are no longer appropriate for the new context, in which people expect to access information in a more flexible and non-intrusive way. Instead of asking people for the certificates, this paper advocates a direct certifying mechanism, in which delegation relationships are directly verified by asking the delegator. By dynamically discovering potential credential chains a trust community is maintained. Existed credential chain discovery methods are not scalable enough for that they either need collecting all credentials in the system or need referring to all the potential users. In our approach, each user keeps a trust list to reduce the fan-out of searching steps. The simulation shows that the performance is greatly improved.