In the world of technology, it doesn't take long: What's new is old again.

The University of Minnesota is replacing its obsolete, seven-year-old campus Wi-Fi network this spring with new equipment that is 10 times faster.

Obsolete Wi-Fi? Isn't that the latest way for laptop PCs and some cell phones to access the Internet wirelessly at high speed?

Yes, but the old campus Wi-Fi equipment, like old PCs, simply doesn't cut it anymore, university officials said.

While the wireless network isn't the main computer artery serving the U -- that's handled by a much faster wired network -- it does provide Internet access for students and faculty traveling around the campus. The trouble is, the Wi-Fi network is a patchwork of outdated equipment that is slow and hard to manage, U officials said.

The new Wi-Fi network, to be installed starting in May, will be faster and more manageable, giving the university the ability to quickly find trouble spots or to kick people off the network for hogging network capacity with downloads or launching Internet attacks, said Steve Fletty, a university network design engineer.

The initial, $3.5 million phase of the Wi-Fi project will cover about 40 percent of the Twin Cities campuses -- mostly inside classrooms and libraries, plus some outdoor locations like the area in front of Northrop Auditorium -- just as the old network did, Fletty said.

The university would like to expand Wi-Fi coverage to 100 percent of its Twin Cities campuses over the next five years, but money hasn't been appropriated for that, said Steve Cawley, the university's chief information officer. The university also is interested in offering Internet telephone service via a campuswide Wi-Fi network, but that would cost another $10 million to $12 million, Fletty said.

The university is taking advantage of the newest Wi-Fi technology that is just becoming available from network equipment makers and laptop manufacturers. Called 802.11n, it transfers data at about 100 million bits per second, compared with existing 802.11b technology that has a speed of 11 million bits per second.

But the actual Wi-Fi speeds at the U could be even faster, Fletty said. Once students have new laptops with the 802.11n technology built in, they could get speeds up to 300 million bits per second, he said.

The new university Wi-Fi network will be about twice as fast as the Minneapolis citywide Wi-Fi network that's just being completed. But that's not a concern, said Joe Caldwell, the marketing vice president of network operator US Internet of Minnetonka. For now, his firm prefers the slower 54-million-bit technology (802.11g) because it is cost-effective and is more widely installed on laptop PCs and on Wi-Fi-equipped cell phones.

But for the university, the decision to go with faster Wi-Fi technology was related to how soon it might have to buy new gear again.

"If we went with 54 million-bit Wi-Fi, we felt like we'd be under pressure to upgrade again in two years," Cawley said. "By going with 100-megabit Wi-Fi, we hope to get about five to six years of life out of it."

Despite the speed differences between their Wi-Fi networks, the university and the city are discussing how to connect them so that subscribers of each could "roam" on the other system, Caldwell and Cawley said.

If any of the U's old Wi-Fi equipment is usable, it will be resold, but much is likely to be of no value because of the rapid obsolescence of computer gear, Cawley said.

In that sense, the university is in the same boat with the city of St. Louis Park, which is negotiating for the disposal of its solar-powered Wi-Fi antennas after a city Wi-Fi network didn't work properly.

Despite a recent $800,000 investment by St. Louis Park, the value of the antennas is unclear, city officials said.

Steve Alexander • 612-673-4553