A Look at the Inner Workings of NSA’s XKEYSCORE

Secondin a series. Part 1 here.

The sheer quantity of communications that XKEYSCORE processes, filters and queries is stunning. Around the world, when a person gets online to do anything — write an email, post to a social network, browse the web or play a video game — there’s a decent chance that the Internet traffic herdevice sends and receives is getting collected and processed by one of XKEYSCORE’s hundreds of servers scattered across the globe.

In order to make sense of such a massive and...