Cyber crime is serious business. This movie gets the verbiage correct, the methodology correct, the capabilities of the IP correct and exposes how crass the internet can be! Explanations for technology are not given. However, remember the buzz words and you can learn about it with an online search!
The internet was originally called DarpaNet, for the Defense Advanced Research Projects Administration. Darpa has the responsibiity of advancing research to aid in the defense of our nation! The results of their work are extensive on the civilian side, so don't put down defense research! The purpose of DarpaNet was to make a Command and Control System, that had no single point of failure, and would allow the US DoD structure to withstand a nuclear attack. DarpaNet met its design goals. We are the benefactors of it. Of course, the WWW was an extension to DarpaNet with the work of HTML and the Browser. This made the Internet what it is today.
Untraceable is the tale of one malevolent www emotionally disturbed user's desire to wrought vengeance on his perceived enemies. The movies plot is tight. Some characters are more completely defined that others. However, the tension and terror built through the second act, with a third act that brings a satisfying conclusion to the story arc. Some story lines are left to the imagination, but so what! What movie completes every story line in less that a week. If this were a movie that extended over a week, with relief breaks for exercise of many forms; well I don't think I would last through such a movie! I think I would be asleep after 240 minutes!