I don't even think SR is on the list of potential targets for intelligence agencies. Intelligence Agencies != Police Agencies. Sure such an agency does not exist. I agree. However it only takes a global passive adversary to pwn all of Tor, and although such an agency may not exist some are certainly close. And a global passive adversary in the context of Tor, rather than the entire internet, is really all that is required. Yes I am sure SR is quite a high priority for all kinds of international federal police agencies, DEA and USPI and ICE are certainly highly interested in SR, Interpol is probably coordinating an international operation against it as we speak, and the Australian federal police have a huge hard on for it, amongst various other international police agencies. None of these agencies are on the level of NSA or CIA. They play a different game with a different list of targets and a different list of targeted activities. They have little cooperation or collaboration with each other, and when they do it is usually with the FBI counter terrorism people, who are also not likely to be the FBI agents trying to attack SR, as SR is not a terrorist organization. They are almost certainly sampling at IX's, although I am not sure it is entirely random or if it is a complete waste of time. They only need one packet per stream to carry out traffic analysis against low latency flows, so that is probably what they are aiming for. If they get a lot of single packets from porn feeds, it will add up to a lot, but it isn't like they are recording the entire download of the porn movie or torrent. Also they almost certainly use various forms of filtering. Or they identify terrorist sites and passively observe them, and then look for people sending packets through proxy services that wind up being identified at the terrorist websites. Although I am sure they also do some analysis of plaintext data looking for terrorist keywords. Most of what they are interested in is going to be encrypted, so they could start by spending more of their resources on encrypted traffic flows. They could also filter off encrypted traffic flows to known as non-interesting sites, like online stores using HTTPS. Most forms of steganography can be detected automatically though .