Maintaining Secure Level on Symmetric Encryption under Quantum Attack

Quantum computing is currently being researched in many countries, and if implemented the near future, it may pose a threat to existing encryption standards. In quantum computer environment, asymmetric can be solved by Shor’s Algorithm polynomial time, difficulty of breaking symmetric using brute force reduced from N times square root Grover’s Algorithm. We take Advanced Encryption Standard as theme increase key length original standard 192 bits 256 384 512 bits, respectively, order maintain security level AES 192/256 under environment computing, so we propose schedule 384/512, write software C++ on FPGA. The experimental results show that our scheme achieve Level III V levels attack environment. addition increasing key, use LUT method process writing SubBytes replace array speed up computation optimize execution speed. addition, proposed still based 128-bit blocks, rather than blocks larger blocks.