Efficient Post-Quantum TLS Handshakes using Identity-Based Key Exchange from Lattices

Identity-Based Encryption (IBE) is considered an alternative to traditional certificate-based public key cryptography to reduce communication overheads in wireless sensor networks. In this work, we build on the well-known lattice-based DLP-IBE scheme to construct an ID-based certificateless authenticated key exchange for post-quantum Transport Layer Security (TLS) handshakes. We also propose concrete parameters for the underlying lattice computations and provide detailed implementation results. Finally, we compare the combined computation and communication cost of our ID-based certificate-less handshake with the traditional certificate-based handshake, both using lattice-based algorithms at similar postquantum security levels, and show that our ID-based handshake is $3.7 \times$ more energy-efficient, thus highlighting the advantage of ID-based key exchange for post-quantum TLS.