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NSA snoops tech companies’ fibre-optic networks

Even though they cooperate with the US spy agency on court-ordered surveillance, firms like Google and Yahoo are subject to additional surveillance they never agreed to
No data is safe
No data is safe
(Image: Google/Rex Features)

The US National Security Agency has access to the internal networks of Google and Yahoo 鈥 and this time even company executives had no idea they had been tapped.

Thanks to documents leaked by former NSA contractor Edward Snowden, we know that tech giants including Google, Yahoo, Apple and Facebook cooperate with the NSA鈥檚 PRISM scheme, which lets the agency request user data through court orders under the Foreign Intelligence Surveillance Act (FISA).

It now seems the agency鈥檚 access goes even further. On Wednesday, The Washington Post reported that to gain direct access to the optical fibre networks linking Google and Yahoo鈥檚 internal data centres, under a separate project codenamed MUSCULAR.

Web companies host copies of your data on servers around the world, reducing the chance of losing your information should one fail. When you log in to an account with these firms, the data sent between you and their servers is encrypted, making it difficult to snoop鈥 but the internal transfers between data centres are unencrypted. And because many of the transfers take place outside the US, approval from a FISA court isn鈥檛 required to tap the information.

Both Google and Yahoo say they did not cooperate with the NSA. 鈥淲e have not given access to our data centres to the NSA or to any other government agency,鈥 said a Yahoo spokesperson. 鈥淲e are outraged at the lengths to which the government seems to have gone to intercept data from our private fibre networks,鈥 Google鈥檚 chief legal officer David Drummond said in a company statement.

According to the Post, GCHQ gathers three to five days of traffic at a time and the NSA uses software filters to keep a subset of it鈥 including text, audio and video content, and metadata on the flow of emails. A top-secret NSA document from January reports over 180鈥痬illion records had been collected in 30 days鈥 a volume of data that even the agency struggles with.

How the data is accessed is unclear. 鈥淭here are ways to get information out of fibre. If you just bend it a bit, light spills out,鈥 says of the University of Southampton, UK, who pioneered many of the fibre-optic techniques used today. In fact, fibre networking equipment already contains such taps to let engineers monitor connection quality.

Rather than tapping the optical signal, though, Payne says it would be easier to wait until the equipment converts it into an electrical signal that computers can read before patching in. 鈥淚 don鈥檛 think the NSA is surreptitiously digging up a cable and sneaking off some data,鈥 he says.

After Snowden鈥檚 first leaks, Google announced , and the latest revelations serve to underline why. Yahoo has not yet announced any encryption plans, but it seems to be the only way to protect against snooping. Web firms can鈥檛 stop using fibres to coordinate their data centres, as alternative technologies such as microwave links are too expensive or unreliable, says Alan Mauldin of TeleGeography, a telecommunications research firm based in San Diego, California. 鈥淵ou鈥檙e not going to see companies moving away from using fibre-optic cables in the near future.鈥

Topics: Computer crime / Crime / Forensics / United States