AC-PKI: anonymous and certificateless public-key infrastructure for mobile ad hoc networks

This paper studies public-key management, a fundamental problem in providing security support for mobile ad hoc networks. The infrastructureless nature and network dynamics of ad hoc networks make the conventional certificate-based public-key solutions less suitable. To tackle this problem, we propose a novel anonymous and certificateless public-key infrastructure (AC-PKI) for ad hoc networks. AC-PKI enables public-key services with certificateless public keys and thus avoids the complicated certificate management inevitable in conventional certificate-based solutions. To satisfy the demand for private keys during network operation, we employ the secret-sharing technique to distribute a system master-key among a preselected set of nodes, called D-PKG, which offer a collaborative private-key-generation service. In addition, we identify pinpoint attacks against D-PKG and propose anonymizing D-PKG as the countermeasure. Moreover, we determine the optimal secret-sharing parameters to achieve the maximum security.