Mobile phones have come a long way since the days where they were only used for phone calls. Since then, simple cell phones largely gave way to the current dominance of smartphones, and part of that dominance began with the underlying technology of 3G wireless technology and CDMA networks. That technology is known as EV-DO. This guide takes a look at what EV-DO actually is, what it does, and how it affects you.

What Is EV-DO?

EV-DO stands for Evolution-Data Optimized or Evolution-Data Only and it’s the mobile broadband technology behind 3G for CDMA networks. Essentially, EV-DO gives phone service carriers with 3G CDMA networks the ability to provide high-speed internet access for mobile devices, providing consumers better access to things like email and online media.

If you currently own a smartphone, it probably runs on a 4G or 4G LTE service. That “G” means “generation,” as in, 4G is the fourth generation of wireless cellular service. But while this network standard is the one you’re more likely to associate with modern-day smartphones, mobile broadband technology began with 3G wireless service, CDMA networks, and EV-DO.

While EV-DO is able to provide (relatively) high-speed internet access for mobile devices, it’s unable to do so during phone calls. As HowStuffWorks once noted, EV-DO was developed to run “over a part of the cellular network devoted entirely to data.” EV-DO works by keeping voice and data channels separate from each other, which allows for optimized data transfers and faster mobile internet access.

CDMA stands for Code Division Multiple Access. Basically, it’s a technology used to run 3G cell phone networks. CDMA-based networks are commonly used by carriers in the United States.

How the EV-DO Network Standard Affects You

If your phone runs primarily on 4G or 4G LTE, EV-DO doesn’t really affect you all that much unless your phone carrier uses a CDMA-based network. In that case, your CDMA-network phone can use a 3G signal as a backup wireless data connection if you find yourself in an area where you can’t access any 4G connections.

It’’s worth noting, however, that 3G CDMA/EV-DO may not be available as a backup in the United States for much longer, especially as more carriers are opting to roll out 5G wireless access to their customers. Sprint will keep offering 3G access until 2022, according to PCMag, but it’s unclear how long it will offer CDMA, and its end “may come in 2020 or 2021.” Verizon will also reportedly retire its 3G CDMA networks by the end of 2020.

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