It’s the end of an era! Or at least, the beginning of a process that will eventually lead to the end of an era. 3G was once the great new hotness that made everyone run out and buy an iPhone, but over the years it’s been left in the dust by faster 4G LTE service. Now Verizon, the country’s largest wireless carrier, has started down the road that will eventually kill off the venerable 3G once and for all.

The folks over at GigaOm have explained what’s going on. There’s a lot of technical information in their post, but the gist of it is pretty straightforward: Verizon’s slowly doing away with their 3G service in order to provide new levels of LTE.

It all boils down to the science of wireless communications. Mobile data is transmitted through radio waves, part of the electromagnetic spectrum. In the U.S., each wireless company has a specific chunk of frequencies in the EM spectrum allotted for their use. (The FCC regulates who gets to use which chunks, mostly through spectrum auctions.)

The last couple of times Verizon expanded LTE (4G) service, GigaOm explains, they put it in “new” chunks of spectrum — sections they had recently purchased or traded for — that weren’t previously in use. But now, as a network analyzer has spotted, Verizon’s newest LTE connections are happening in bandwidth frequencies that they’ve had for a long time, and that they used to use for older tech. Basically, as GigaOm puts it, Verizon is “cannibalizing” old bits of their network in order to do upgrades and expansions.

Of course, what happens when you Frankenstein something new together is that the parts aren’t in the old system anymore. With the frequencies that once supported Verizon’s 3G network now taken up with its 4G network, the 3G network is shrinking.

Representatives for Verizon confirmed to GigaOm that they are testing changes, and that eventually — at some point in the undetermined future — they plan to convert all of their networks to LTE.

But that time is definitely not yet. 80% of Verizon’s mobile traffic does go through LTE, according to GigaOm… but Verizon is the nation’s largest mobile carrier by far, and those 20% of customers using 2G and 3G devices still add up to about 40 million people.

The evolution and dominance of mobile voice and data was quick, taking place over mostly the last 15 years, and as tech evolved rapidly networks became something of a hodgepodge amalgam of technologies. Verizon’s on the long, slow path to full standardization. But tech being what it is, we might well be two iterations past 4G LTE by the time they get there.

Verizon starts killing off 3G networks to make room for LTE [GigaOm]

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