At a secluded, nondescript – but very secure – facility in North Raleigh, AT&T (NYSE: T) is preparing to roll out “4G” wireless broadband service for the Triangle.

“This is the pulse of what we do,” said AT&T’s Shayne Sage, the network operations manager of AT&T’s wireless hubs.

In what company executives said was a first, AT&T opened the doors wide open for the media and invited guests on Wednesday so they could get a better idea of what the network’s heart does.

Multi-colored fiber optic and other cables – the blood vessels of the pulse, if you will -give the cavernous facility a festive if snakelike décor in some areas.

Covering some 10,000 square feet as estimated by Sage, the building that opened in 2005 is known as a “mobile telephone switching office” or MTSO. These hubs handle traffic received over the cell network as well as landline calls being routed to wireless customers.

The AT&T’s ranking criteria for its operation centers reflects an MTSO’s importance.

“Priority 1,” said Sage, on a scale of 1-5 with 5 being the lowest.

Inside are two massive switches that in actuality are racks of equipment which currently support older 2G and 3G services. Interestingly, the amount of gear required for 3G is less than half the five rows needed for 2G. When 4G gear is emplaced, even less will be required, Sage explained.

Some 4G gear is already in place.

Similar to data centers such as those built by hosted services providers such as Windstream Hosted Solutions and Peak 10, the AT&T building has a massive backup generator in the event of a power failure.

“We could probably run a week” without power from the outside, Sage said with pride. Backups, he added, ensure that there would “not be a blip” if there were a power failure.

To ensure there aren’t any blips, his team regularly “runs exercises” to check that all is in order, he added.

To further ensure seamless a power supply for the switches, the center runs them off of massive batteries. Located in a separate room, the batteries are packed into 13 racks with 24 batteries in each. Each battery has a life span of 30 years and all are maintained constantly, Sage explained.

So how much power do they pack? Said Sage with pride: “We could run 17 hours easily just in batteries.”

(Read here for details about AT&T’s planned 4G rollout.)

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