Provably secure public key management protocols for self-organized ad hoc networks

In traditional public key infrastructures, centralized certification authorities are indispensable for managing public key certificates that are used to provide the witness of certain NP relations. However, it is difficult to deploy centralized certification authorities in ad hoc networks due to the lack of infrastructure and other central services. Nevertheless, public key management protocols-the fundamental security issues, should be proposed to nodes in a self-organized ad hoc network so that each node within this group can collaborate to others to compute certain tasks if its certificate is valid. In this paper, a secure yet efficient group signature scheme is first constructed which is provably secure within our model assuming that the strong RSA problem defined over Z/sub n/*, together with the decisional Diffie-Hellman defined over the quadruple residue QR/sub N//spl epsi/Z/sub N/* is hard. We then propose a public key management protocol for self-organized ad hoc networks by simply assuming that a group manager issues certificates to the nodes who want to join in and at the same time it revokes the certificates related those who are leaving. The technique presented in this paper is universal, and it can be used to numerous applications, e.g., the construction of anonymous routing protocols and incentive-based services in social networks, and so on.