Neither Sprint nor Verizon Wireless — the 3GPP2's usual standard-bearers in the U.S. — have made any firm commitment to pursuing UMB. In fact, Sprint is fairly resolute that it has found its 4G technology: WiMAX. Ali Tabassi, vice president of technology development for Sprint, said that LTE, UMB and WiMAX fundamentally are the same technology on the downlink — all three using OFDM and multiple input/multiple output antenna technologies to achieve higher data rates and lower latency than their CDMA-based 3G forbearers. UMB may eventually be optimized for CDMA operators and LTE for GSM/UMTS carriers, but WiMAX is available today. After deploying a nationwide WiMAX network, there would be no strategic reason to deploy a new network that provided essentially the same benefits, Tabassi said.

“Realistically, we're already building an OFDM technology,” Tabassi said. “It doesn't make sense to deploy a different OFDM technology several years from now.”

Verizon Wireless hasn't thrown its hat into any 4G arena just yet, and Dick Lynch, executive vice president and chief technology officer, said the carrier isn't favoring a particular camp despite the mobile carrier's past embrace of the 3GPP2's work. Like Sprint, Verizon Wireless is taking the approach that it's all OFDM, so there's no inherent advantage — at least not now — of one technology over another. But Lynch is taking his considerations one step further: He's not sure if there's a need for 4G at all.

“Let's back into this question,” Lynch said. “Let's ask ourselves what do we need this technology for? What do our customers need that they can't get on 3G? I think the jury is still out there.”

At the same time, Lynch said he isn't ignoring 4G. He's examining and weighing future technologies and how they best fit into Verizon Wireless' network strategy. From his point of view, though, LTE, UMB and WiMAX are all on equal footing as far as performance is concerned. They all promise the same higher speeds, lower latency and flat IP architectures that would make deploying one as advantageous as deploying another, Lynch said. Verizon Wireless will make a technology decision when an application and a viable business model emerge that will necessitate a choice, he said.

There are even 3G technologies available soon that might be more powerful than the industry can imagine needing at the moment, Lynch said. For instance, the next progression on the CDMA2000 evolutionary path: EV-DO Rev. B, which aggregates Rev. A channels, creating a high-capacity “super” channel that offers compounded peak data speeds of 7 Mb/s or even greater if more than two channels used.

Lynch pointed out that its Rev. A rollout — scheduled for completion this year — gives Verizon Wireless a network with broadband speeds on the uplink and the downlink, latency low enough to support real-time applications like multiplayer action gaming, and the quality of service necessary to support voice over IP. Rev. B is bigger and badder than Rev. A, but is it really necessary? Lynch asked.

“It's certainly compatible with what we've done with the network so far,” Lynch said. “But what is the application that needs Rev. B that can't be enabled on Rev. A?”