Public key crypto key exchanges (RSA, D&H, ECC) would be ‘flat-lined’ under a quantum computer attack … "Open Problem”

Brian Snow, Former Technical Director of the US National Security Agency (NSA), Public Key Cryptography 30th Anniversary Conference, Dec 2006

“a significant breakthrough in quantum computation would spell doom for all these systems (ECC-192 or RSA-2048).”

European Network of Excellence for Cryptography, "D.AZTEC.2 Alternatives to RSA", July 2005

"Many crypto-systems considered robust have been broken after a certain amount of time (between 10-20 years).  ... We need to build crypto-systems that offer long term security, for example for protecting financial and medical information (medical information such as our DNA may be sensitive information with impact on our children, our grandchildren and beyond)."