Another top-secret document described NSA efforts to tap into the SEA-ME-WE-4 undersea telecommunications cable, which stretches from southern France to Thailand and connects Europe with North Africa and the Middle East.
On Feb. 13, the TAO "successfully collected network management information" for the cable, including Layer 2 information that shows circuit mapping, Der Spiegel reported, quoting the document.
Der Spiegel further described some of the TAO's computer exploitation activities, which include trying to redirect a targeted person's computer to servers controlled by the agencies that can deliver spyware.
The NSA and its U.K. counterpart, GCHQ, use a tool called QUANTUMINSERT to tracks a person's internet browsing and at opportune moments direct the user's computer to one of its FOXACID exploitation servers.
One document showed that QUANTUMINSERT was most effective when people were trying to visit the professional networking site LinkedIn, Der Spiegel said. The success rate was more than 50 percent, it said.
The NSA could not be immediately reached for comment Sunday night.
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