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More than 50 big names in the fields of computer science, security, and cryptography have published an open letter calling for an end to the NSA's controversial spying practices, including reported efforts to undermine encryption and network-security standards.

"Every country, including our own, must give intelligence and law-enforcement authorities the means to pursue terrorists and criminals, but we can do so without fundamentally undermining the security that enables commerce, entertainment, personal communication, and other aspects of 21st-century life," reads the letter, which is signed by, among many others, Edward Felten and Steve Bellovin, both former chief technologists for the Federal Trade Commission.

Other signatories include Shai Halevi, director of the International Association for Cryptologic Research, and researchers from MIT, Georgia Tech, Carnegie-Mellon, Princeton, Yale, Harvard, and a raft of other respected universities.

The NSA has sidestepped common Net encryption methods in a number of ways, including hacking into the servers of private companies to steal encryption keys, collaborating with tech companies to build in back doors, and covertly introducing weaknesses into encryption standards, The New York Times, The Guardian, and ProPublica reported in September, citing agency documents leaked by Edward Snowden.

The recently released report by President Obama's handpicked NSA Review Group said the group was "unaware of any vulnerability created by the US government in generally available commercial software that puts users at risk of criminal hackers or foreign governments decrypting their data."

But it also included recommendations that the government should not engage in such activity, should "fully support" encryption standards, and should "increase the use of encryption and urge US companies to do so." The group's suggestions also touched on hacking and other information security issues, saying, in essence, that the NSA needed to tread very lightly in these areas. (For details, see Chapter VII -- pages 209 through 231 -- of the group's report [PDF].)

In his NSA reform speech last week, Obama didn't address those recommendations in detail, saying instead that he'd ordered "a comprehensive review of big data and privacy" involving government officials and the President's Council of Advisors on Science and Technology. The review, he said, would "reach out to privacy experts, technologists, and business leaders" to determine "how we can continue to promote the free flow of information in ways that are consistent with both privacy and security."

Here's the full text from today's open letter. The complete list of signatories is here.