"It's a megatrend that we are aware of here," Cannistra said.

Farther down the road, past 4G, Ephremides sees what he calls full-fledged multi-hop ad hoc networks, something the U.S. military is currently investigating.

"Currently, when your BlackBerry goes to a base station, everything goes in one hop," he said. "This [multi-hop ad hoc networking] would involve multiple hops to the base station -- you'd go through other users, so some users would be like passive repeaters bouncing other people's signals. Ad hoc networking means no infrastructure."

Current Wi-Fi mesh networks, such as those being installed by some municipalities to cover an entire metropolitan area, are crude versions of such networking, Ephremides said.

"But they still require very densely placed access points," he said. "[Ad hoc networking] would free you of that, so in a couple of decades, that older type of architecture will be passe." He acknowledged, however, that while the military has been pushing development of such networks, early versions don't work very well.