A lot people are concerned that the NSA might be monitoring the international communications of US citizens. Some might even wonder if they personally have been affected by NSA snooping.
If you are one of these people, just relax. I can safely state that the NSA has, without a doubt, listened to or read virtually all the communications you sent overseas. They have to. Given the nature of modern telecommunications, it’s the only way they can fulfill their mission.
Most people’s idea of the technical aspects of the NSA’s work comes from the old practice of tapping analog phone lines. In the old days, tapping a phone meant attaching an electronic device directly to a specific physical wire that carried the conversations from a specific set of phones. With analog lines, the authorities could easily determine if they were listening to a conversation that their writ covered before they heard a word.
It doesn’t work that way anymore. All electronic communications, whether voice, email, webpages, bittorent, etc. all travel across the same physical networks while chopped up into sub-units called packets. By analogy, sending a communication via packets is like taking a hardcopy letter and cutting it up into several pieces. You then send those pieces separately to their destination. You would send one by the postal service, another by FedEX, another by UPS, another by your cousin Ted who’s flying there anyway, etc. At the destination, the individual pieces would be taped back together to form the original message.
Practically, this means you cannot know anything at all about a packet-based communication until you “trap” the packets associated with it and reconstruct the original communication to some degree. Simply monitoring a particular piece of hardware tells you nothing since the same hardware carries multiple communications simultaneously, and one of the strengths of packet-switched networks is that packets don’t have to travel the same path over the same hardware. To capture a particular communication, you must cast a wide net and capture all the associate packets and reassemble them.
This technological reality creates a legal paradox. In order to determine whether the NSA has the legal right to monitor a communication, the NSA must first read the communication. A day at the office in the NSA must be a long series of, “Not supposed to read that. Nor that, and I really shouldn’t have read that!” Supposedly, the NSA deals with this problem by having a 72-hour time window in which to decide if they have the legal right to monitor a particular communication. If not, then they erase the captured information.
The fact remains, however, that some person or (more likely) automated system does process the communications of large numbers of totally innocent US citizens, without any warrant, on a continual basis, and that they have been doing so for many, many years. We must simply trust that they have been scrupulous in deleting information they shouldn’t have access to.
I strongly suspect that the “spying on US citizens” in the current scandal will turn out to be NSA standard procedure that they have followed for nearly two decades. The only shift that could have occurred will be in the type of information they discard, not in what information they actually captured.
The bad news is that Big Brother is definitely watching you. The good news is that he probably isn’t paying much attention.