A lattice-based forward secure IBE scheme for Internet of things

Abstract

The Internet of Things (IoT) is gaining popularity as it can effectively connect the real world with the Internet. However, security and privacy issues are widely considered the major obstructions to its widespread adoption. Hence, various cryptographic tools (e.g., encryption and signature schemes) have been proposed to build secure and authenticated channels for data communication in IoT. In this work, we investigate the well-known encryption scheme called identity-based encryption (IBE) for IoT-oriented applications. In particular, we are mainly interested in forward-secure IBE (fs-IBE) which could still protect the data transferred in the past when the current secret key stored in the IoT device is stolen. To this end, we propose an fs-IBE scheme which, as far as we know, is the first construction of fs-IBE that can resist quantum attacks. Our scheme is based on the lattice-based hardness assumption namely Learning with Error (LWE), which is widely adopted for designing other quantum-resistant cryptographic schemes. At the core of our design is the minimal cover mechanism in the context of binary tree and we rigorously prove the security of our scheme in the forward-secure, selective ID, chosen-plaintext attack (CPA) model. Besides the post-quantum security, our scheme enjoys comparatively compact ciphertext and secret key, and thus it is suitable for bandwidth-limited IoT communication.