U.S. mobile carrier giant Sprint announced this week that it has chosen Mobile WiMAX as the technology for its 4G network evolution, thereby helping make Mobile WiMAX synonymous with 4G.

But what exactly is 4G? Is it personal broadband, the WiMAX Forum's personal cause celebre? To many in the mobile industry, the 3GPP's Long Term Evolution standard still represents 4G. So if Mobile WiMAX is 4G for Sprint, than will LTE be 5G for Sprint and everyone else?

I don't pretend to know the questions to these answers, and perhaps the answers don't matter, as different carriers around the world may adopt different technologies at radically different paces, and may even skip solutions that represented significant generational upgrades for others.

And if the IP multimedia subsystem movement accomplishes what it set out to do, none of this may matter. Mobile or WiMAX access architectures will become increasingly transparent, and thus the adoption of multiple architectures by a single network operator increasingly common. But, what if you use Advances to IMS (Verizon Wireless' recent enhancement proposal) instead of IMS?

Technologies come in numerous flavors and have different labels attached to them, but that doesn't mean they are moving in different directions. A-IMS and IMS share the same core technology philosophy, and all the technologies that Sprint considered for 4G have something in common, too--orthogonal frequency division multiplexing.

Forget about WiMAX or LTE or any of those generational labels. We're all moving in the same direction, more or less...

E-mail me at doshea@telephonyonline.com.
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