The development of large quantum computers will have dire consequences for cryptography. Most of the symmetric and asymmetric cryptographic algorithms are vulnerable to quantum algorithms. Grover's search algorithm gives a square root time boost for the searching of the key in symmetric schemes like AES and 3DES. The security of asymmetric algorithms like RSA, Diffie Hellman, and ECC is based on the mathematical hardness of prime factorization and discrete logarithm. The best classical algorithms available take exponential time. Shor's factoring algorithm can solve the problems in polynomial time. Major breakthroughs in quantum computing will render all the present-day widely used asymmetric cryptosystems insecure. This paper analyzes the vulnerability of the classical cryptosystems in the context of quantum computers discusses various post-quantum cryptosystem families, discusses the status of the NIST post-quantum cryptography standardization process, and finally provides a couple of future research directions in this field.

翻译：大型量子计算机的开发将给加密系统带来严重后果。 大部分对称和不对称加密算法都容易受量子算法的影响。 Grover的搜索算法为在AES和3DES等对称方案中搜索关键数据提供了平方根时间的加速度。 诸如RSA、 Diffie Hellman和ECC等不对称算法的安全性基于质因子化和离散对数法的数学硬度。 最佳古典算法需要指数化的时间。 Shor的推算算算法可以解决多种时间的问题。 量子计算的重大突破将使当前所有广泛使用的不对称加密系统变得不安全。 本文分析了量子计算机背景下古典加密系统的脆弱性, 讨论各种Quntum后加密系统家庭, 讨论NIST后Qunetum加密系统标准化进程的状况, 并最终提供了该领域的几项未来研究方向。