Last year I had the pleasure of paying AT&T’s global network operations center a visit. You can read about the trip here.

For a tech nerd like myself, this is Disney World. (No lines either!) Within the facility, AT&T’s technicians oversee all of the data about all the data that people are sending one another over the company’s vast network. The many, many displays in this building depict where calls are coming from, how info-packets are flowing from wire to wire, who may be experiencing issues, and what might need fixing. If the network is a nervous system, then this is its brain.

On any given day, AT&T (T) handles 100 petabytes of data traffic. This isn’t just big data—it’s ginormous data. As of April 2011, the United States Library of Congress had stored an estimated 235 terabytes of data, as Computer Weekly relates, citing McKinsey statistics—multiply that by 400 and you’ll get an idea of the amount of information coursing through the company’s infrastructure on a single day. Yep, it’s a lot.

All of this insight helps AT&T’s network engineers tune its systems to keep people’s wireless devices plugged in, up and running. Cybersecurity is a top concern, of course. If the systems detect a swelling of traffic—a data surge—that might indicate that a distributed denial of service attack is underway. A hacker could be summoning a botnet strike. Cue automated mitigation maneuvers.

AT&T is a behemoth, ranking at number 12 on the most recent Fortune 500 list. It’s the largest telecom carrier by Fortune’s ranking, followed by Verizon (VZ) at number 15. (We’ve begun work on the new list, by the way, due out this summer.) And the company’s central command does not disappoint.

Hope you enjoy the tour.