An authentication scheme for three-party mobile Conditional Access system(CAS)

In this paper, we redefine the roles in Mobile-TV systems from two parties(service provider and user) to three par-ties(network operator, content provider and user). Afterwards, we concentrate our discussion on service authentication problem in three-party model. Our proposed scheme is based on Identity Based Encryption(IBE) scheme, give a novel way to solve the mutual authentication and batch authentication problems. Our scheme inherits the advantages of IBE scheme which the public keys don´t need to be certificated, the certification Authority mechanism will not be needed and the key exchange overhead can be reduced. Our scheme achieves better performance in storage, communication and computation comparing to traditional authentication schemes.