"One often hears recommendations for key-sizes of public-key cryptosystems needed to obtain security for 30 years and even 50 years. Anyone wanting a real security of this magnitude should probably take the construction of the quantum computer into consideration."

ECRYPT, “D.PROVI.3 – First Summary Report on Unconditionally Secure Protocols”, January 2005

"Unfortunately, the security issues of a technology near the end of its lifetime are typically overlooked.  The best known example is that of cryptographic keys and algorithms which may need to offer in some cases security for 50 to 100 years."

"Even a relatively small quantum computer, one that had a few tens of thousands of qubits, could consider so many different values at once that it would be able to break all known [ed: RSA, D&H, ECC, AES-128] codes commonly used for secure Internet communication.”

Prof Seth Lloyd of MIT, MIT Review 2008