There’s been a frenzy of activity in recent months among service providers and equipment suppliers that want to outfit 4G network builders with backhaul solutions. Indeed, wireless backhaul is among the key applications driving new investment by existing and new fiber optic companies, as well as companies using other technologies such as microwave.

Benjamin Edmond, executive vice president of sales and marketing at FiberLight (News - Alert), which offers lit services and dark fiber over a network that spans from Baltimore to Miami to Texas, says there’s been a lot of investment in fiber over the last could of years both due to wireless backhaul requirements, the government moving from TDM to Ethernet, the video boom, growing storage requirements, and the rise of cloud computing and software as a service.

For example, Allied Fiber (News - Alert), the new venture of Hunter Newby (who was part of the team who built and later sold Telx), is creating a dark fiber network in the U.S. Part of Allied Fiber’s plan is to offer wireless network operators and their wholesale backhaul suppliers both dark fiber, and space on radio towers along its fiber routes, which run along Norfolk Southern rights of way. Those rights of way already are dotted with towers, which Allied Fiber will help the railroad lease to interested parties.

Gary Bolton, vice president of global marketing at ADTRAN (News - Alert), says that while 4G wireless builds have gotten a lot of attention in recent months, a big part of the network that enables mobile communications is wireline.

“Wireless is really a wireline network,” says Bolton.

Cellular networks commonly rely on wireline links for backhaul. And strategies for offloading wireless traffic to wireline infrastructure continue to proliferate as the need for bandwidth outpaces available spectrum, says Bolton, noting that the FCC (News - Alert) recently released a study showing wireless spectrum will soon run out if the government doesn’t make more available.