ORLANDO, Fla. -- COMPTEL Plus Fall 2013 – Given the rains drenching Disney World this week, the happiest place in Orlando might well be the Gaylord Convention Center, where competitive carriers and wholesalers all seem to be wearing big smiles.

After a period of relative gloom, the vibe this year at Comptel is much more upbeat, as service providers and equipment vendors are seeing better times ahead, thanks largely to some intersecting trends: the bandwidth boom attributed to smartphones and wireless growth, and the arrival -- at last -- of the long-predicted IP transformation, which is enabling new hosted VoIP, Unified Communications and cloud services.

"Everyone is very positive right now -- as much as this industry has taken its lumps, we are seeing demand growing from the wireline and the wireless backhaul side," says Jack Waters, CTO of Level 3 Communications Inc. (NYSE: LVLT).

Unlike wireless network operators, who have to figure out how to monetize their network upgrades, the wireless boom is mostly gravy for the folks building fiber-to-the-tower, even if the actual building of the fiber networks that backhaul wireless voice and data is, itself, back-breaking work.

For regional fiber carriers such as Tower Cloud Inc. and FirstLight Fiber , formerly known as Tech Valley Communications, the push is on to be the company that gets fiber to the tower first, and to be certified by the wireless operators for their preferred Ethernet services. Tower Cloud this week announced a major network upgrade to deliver more bandwidth over its fiber in the southeastern US. (See Tech Valley Becomes FirstLight Fiber.)

"We've seen tremendous growth in the backhaul market for both metro areas and rural areas," says George Townsend, SVP, business development for Tower Cloud. "We're seeing the wireless carriers work harder to fill in the gaps in their coverage -- what used to be called cell-splitting."

Regional fiber networks are often in a better position to provide mobile backhaul because of their deep penetration of areas, such as Tier 2 and Tier 3 markets, where there is less competition, says Kevin O'Connor, president and CEO of FirstLight.

But there are other, possibly more surprising, aspects to the business uptick for competitive carriers. Voice services, of all things, are back in vogue -- at least as hosted VoIP and voice components for UC offers. That's creating business for the networks that provide the connectivity backbone for reaching all the businesses buying those services.

"We are finally seeing things move in the direction of IP," says Gary Zimmerman, head of marketing for the communications segment of Neustar Inc. (NYSE: NSR). While IP is enabling a wide range of hosted and managed services, he adds, "traditional" VoIP in particular is making a comeback.

Some of the buzz around traditional VoIP is being fueled by the belief that the Federal Communications Commission (FCC) is ready to allow VoIP providers to have access to phone numbers, following a trial it is currently conducting with Vonage Holdings Corp. (NYSE: VG). But as multiple discussions and one contentious panel here at Comptel show, that step is far from a done deal, and is likely to take more regulatory action at the state level as well.

Even without access to numbers, however, VoIP services are popular for hosted voice delivery to a range of businesses, and wholesale VoIP is enabling more efficient aggregation of services for carriers.

Bandwidth.com , which announced Phone.com as a customer here at Comptel, is using its national CLEC status to support a number of wireless MVNOs and so-called "freemium" services but also is seeing 20 percent growth in its wholesale business in part because as traditional voice revenues decline, voice is being integrated in innovative ways into other applications.

"With unified communications getting actual traction, we are selling wholesale services, including SIP trunking on a per-seat basis, to a lot of mid-tier service providers, where there is growth," says Ken Grelck, SVP of Bandwidth.

Windstream Communications Inc. (Nasdaq: WIN) is carving out a rapidly growing wholesale business by offering MPLS aggregation for hosted VoIP providers, which want Layer 3 aggregation because of the additional security, says Patrick Herron, VP Enterprise Product Marketing.

"We're also seeing growth with cloud service providers and managed service providers for this service as well," Herron says. "We are finding we can meet the less-served needs of regional carriers who are seeking to terminate traffic in areas where they don't have networks.

One Source Networks , which recently added points of presence in New York and Los Angeles, as well as London, Hong Kong, and Bogota, Colombia, also is seeing growth in the business of layering voice and managed services traffic over the data network. Large enterprises and carriers are looking for ways to simplify their network operations, phase out TDM voice, and move where possible to cloud-based services.

"One of the things we can do is help them at whatever phase of the transition they are at, to get to where they want to be, whether that's moving to Ethernet and VoIP or replacing analog gear with a cloud-based PBX or a hybrid of cloud and digital PBXs on premises, says Gina Nomellini, chief marketing officer.

— Carol Wilson, Editor-at-Large, Light Reading