“We are giving a decade worth of pre-warning,” Khurjekar told Fierce. But even 2021 may be too soon. A Verizon Wireless spokesperson clarified with Fierce that that 2021 is the year to which Verizon is committing to keep its 2G and 3G online so its enterprise and M2M customers can make long-term plans. Verizon has set no firm timeline for shuttering its CDMA network at all, and will continue to offer 2G and 3G as long as it customers want it.

Verizon’s 2G/3G coverage is in red. Its LTE markets are in yellow.

The rest of the mobile industry sees a bit more urgency. AT&T has said it would shut down its 2G network by 2017. It’s already started repurposing old GSM spectrum for HSPA, and there are signs that it is considering a LTE launch in its 2G cellular and PCS frequencies as well. Sprint is finally shutting down Nextel’s old 2G network, refarming its frequencies for 4G. Meanwhile, T-Mobile has lopped off most of its GSM capacity to clear room for more HSPA+ and a new LTE service.

Why isn’t Verizon in a hurry to cannibalize its older technologies as well? For one, Verizon is in the best 4G LTE position of all of the Big 4 operators. After scooping up a bunch of 4G licenses from the cable companies, Big Red has the airwaves to launch a new nationwide LTE network parallel to the one its already deployed.

Also, even if Verizon doesn’t shut down 2G and 3G sites for another nine years, there’s nothing stopping it from whittling away at them. Verizon’s CDMA 1X and EV-DO technologies can persist on very little bandwidth, meaning Verizon could keep nationwide 2G and 3G networks with only a handful of megahertz. It could then take the rest of its cellular and PCS spectrum and put it to 4G use.

Verizon will have to keep a modicum of CDMA online for the foreseeable future though. In 10 years our handsets and tablets will have fully completed the jump to 4G, but there will still be CDMA radios embedded in cars, shipping containers, industrial equipment and even vending machines and jukeboxes, all of which will need a network to link to. Verizon will want to keep those lucrative revenues coming.

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