In recent years, there has been significant progress in the development of quantum computers, which perform computations based on the principles of quantum mechanics. Quantum algorithms are much different in nature than classical algorithms, but they are known to provide speedup over classical algorithms for certain problems. Currently, two of the best-known quantum algorithms are Grover's algorithm for unstructured searches, and Shor's algorithm for factoring numbers. These algorithms are known to pose a threat to currently used cryptographic systems, but there are currently no quantum computers powerful enough to execute them. If a large-scale quantum computer is ever built, many public key cryptography schemes would be broken by Shor's algorithm. For this reason, research is being done in the area of post-quantum cryptography. Secret key cryptography schemes will fare better, as the threat posed by Grover's algorithm is easily mitigated by doubling the key length.

report

source code: browse, download