Patterned Cipher Block for Low-Latency Secure Communication

Abstract

Despite the increasing importance of network security, increasing Internet of Things (IoT) uptake and traffic tends to apply tighter resource constraints for cryptography. To cope with the constraints, security systems must choose between time cost and security. Cyber-attack model evolution and quantum computing technologies have severely limited current cryptography uptake and imposed too much overhead to operate effectively on lightweight communication environments. Therefore, we propose a new operation mode using multiple symmetric key ciphers alternately in a regularized order. The proposed design exploits lightweight cryptography methods, reducing encryption/decryption overhead compared to a single heavy cryptography approach, as well as avoiding exhaustive key extraction attack. Since sequences can change both time cost and security performance widely, the design can be applied to various situations, from the delay-constrained communications to highly secure networks. Our cryptography design incorporates patterned cipher block (PCB) operation, an integrity verification technique to identify if a ciphertext has been forged, handshaking protocol exchanging pattern information and a key using two-round communication, and pattern optimization to maximize the cryptographic performance. We confirmed the proposed operation mode numerically, and verified the outcomes experimentally, confirming that the proposed scheme outperformed current best practice cryptography.