NSA seeks to build quantum computer that could crack most types of encryption

In room-size metal boxes ­secure against electromagnetic leaks, the National Security Agency is racing to build a computer that could break nearly every kind of encryption used to protect banking, medical, business and government records around the world.
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, Md.
[Read an annotated description of the Penetrating Hard Targets project]
The development of a quantum computer has long been a goal of many in the scientific community, with revolutionary implications for fields such as medicine as well as for the NSA’s 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 about whether the NSA’s efforts are more advanced than those of the best civilian labs. Although the full extent of the agency’s research remains unknown, the documents provided by Snowden suggest that the NSA is no closer to success than others in the scientific community.
“It seems improbable that the NSA could be that far ahead of the open world without anybody knowing it,” said Scott Aaronson, an associate professor of electrical engineering and computer science at the Massachusetts Institute of Technology.
The NSA appears to regard itself as running neck and neck with quantum computing labs sponsored by the European Union and the Swiss government, with steady progress but little prospect of an immediate breakthrough.
“The geographic scope has narrowed from a global effort to a discrete focus on the European Union and Switzerland,” one NSA document states.
Seth Lloyd, an MIT professor of quantum mechanical engineering, said the NSA’s focus is not misplaced. “The E.U. and Switzerland have made significant advances over the last decade and have caught up to the U.S. in quantum computing technology,” he said.
The NSA declined to comment for this article.
The documents, however, indicate that the agency carries out some of its research in large, shielded rooms known as Faraday cages, which are designed to prevent electromagnetic energy from coming in or out. Those, according to one brief description, are required “to keep delicate quantum computing experiments running.”

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