基于格的可撤销身份加密方案OA

In urban intelligent transportation management systems,the diversity of user identities and the sensitivity of data impose heightened requirements on identity management and data security.To address the shortcomings of existing identity-based encryption(IBE)schemes in terms of key-update efficiency,dynamic user revocation,and resistance to quantum attacks,this paper proposes a revocable identity-based encryption scheme built on lattice-based cryptography.The scheme integrates lattice-based cryptography with a binary-tree data structure and introduces a minimal-cover mechanism to reduce the computational complexity of key updates,thereby achieving an efficient key-refresh process.By monitoring system state and leveraging a global revocation list,it supports real-time,non-interactive dynamic revocation of user identities.From a security perspective,the construction is grounded in the learning with errors(LWE)problem,providing resistance against quantum-computing attacks;its indistinguishability under identity-based chosen-plaintext attacks(IND-ID-CPA)is rigorously proven in the random-oracle model.Extensive simulations demonstrate that the proposal excels at key updating,dynamic revocation,and real-time data processing within urban intelligent-transportation management systems,satisfying the demands of large-scale device management and highly dynamic user scenarios while guaranteeing strong system security.