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Related: Editorials & Other Articles, Issue Forums, Alliance Forums, Region ForumsNSA seeks to build quantum computer that could crack most types of encryption
According to documents provided by former NSA contractor Edward Snowden, the effort to build a cryptologically useful quantum computer a machine exponentially faster than classical computers is part of a $79.7 million research program titled, Penetrating Hard Targets. Much of the work is hosted under classified contracts at a laboratory in College Park.
The development of a quantum computer has long been a goal of many in the scientific community, with revolutionary implications for fields like medicine as well as for the NSAs code-breaking mission. With such technology, all current forms of public key encryption would be broken, including those used on many secure Web sites as well as the type used to protect state secrets.
Physicists and computer scientists have long speculated whether the NSAs efforts are more advanced than those of the best civilian labs. Although the full extent of the agencys research remains unknown, the documents provided by Snowden suggest that the NSA is no closer to success than others in the scientific community.
More at : http://www.washingtonpost.com/world/national-security/nsa-seeks-to-build-quantum-computer-that-could-crack-most-types-of-encryption/2014/01/02/8fff297e-7195-11e3-8def-a33011492df2_story.html
longship
(40,416 posts)The theoretical basis is not yet nailed down as even possible, let alone practical. Yes, there is enough plausibility for there to be research, but not enough that we are going to see quantum computers soon. Plus, it is more likely to be done first at a place like MIT than NSA, and then first only on a small scale, very few qubits. Not very practical.
Then there's the big problem of how the hell do you even interface to the damned thing without screwing up the coherence. No coherence; no quantum computing.
JVS
(61,935 posts)I remember that encryption generally relies on the lack of an "efficient" factoring algorithm, with "efficient" meaning a process that means IIRC at best a linear expansion of processes required as the number to be factored increases. So, my question is: how are they planning on getting around the lack of an efficient algorithm?
Locut0s
(6,154 posts)In the world of quantum computers where a qbits can take on any of a range of values simultaneously, there are quantum algorithms that are efficient.
longship
(40,416 posts)Cryptography depends on trap door algorithms, which can be solved one way, but where there is no analytic inverse function, forcing one to perform exhaustive search. Finding prime factors of very large integers is one of those trap doors. When a large number is the product of two very long prime numbers it is extremely difficult, if not impossible in practice, to discover the factors in a reasonable length of time.
Theoretically a quantum computer could short circuit this process by using its capabilities for massively parallel calculations, which is why NSA has a high interest.
But as I wrote above, I am not concerned that practical quantum computers will be seen any time soon. They may not ever happen. It's a very difficult problem if it is possible at all.