Anonymity’s toughest adversaries are hackers with the full-force and backing of Beijing, London, and Washington, D.C.
With the threat of powerful intelligence agencies, like the NSA, looming large, researchers have built a new Tor client called Astoria designed specifically to make eavesdropping harder for the world’s richest, most aggressive, and most capable spies.
http://www.dailydot.com/politics/tor-astoria-timing-attack-client/