UniCrypt-Ultra: A 64-Bit Quad-Core Universal Cryptographic Engine for Multimode Cryptographic Processing in Blockchain IoT and Society 5.0

This paper presents UniCrypt-Ultra, a 64-bit quad-core universal cryptographic engine designed to support both 32-bit and 64-bit cryptography, including hash functions and stream ciphers. The proposed design targets high flexibility and optimal energy efficiency for blockchain-based IoT and Society 5.0 security systems. To achieve this, three key innovations are introduced: Bandwidth-Aware Memory System with Unified Register Sharing, Multi-Mode Crypto-ALU with 64-bit Adder Sharing, and Stream-Aware Buffering and Pipelined Multi-Core Execution. The implementation on an Xilinx ZCU102 FPGA demonstrates support for eighteen cryptographic algorithms, including SHA-family, BLAKE variants, ChaCha20, and Salsa20, and achieves up to 7.25 times higher throughput than our prior UniCrypt design under the same ZCU102 platform. In addition, across reported FPGA results from different device families, UniCrypt-Ultra achieves frequency-normalized throughput (Mbps/MHz) improvements of up to 640.67 times and energy efficiency gains of up to 596.2 times compared to related works. Moreover, ASIC synthesis results on a 45nm technology node show that UniCrypt-Ultra achieves a 91.72% unified efficiency and delivers up to 6.5 times higher throughput than state-of-the-art CGRA-based designs.