AT&T is ending its 2G, or second-generation wireless network, in five years, making room for its next-generation 4G network.
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The American telecom company revealed its plan in a Securities and Exchange Commission filing on Friday.
"We expect to fully discontinue service on our 2G networks by approximately January 1, 2017," the filing said. "We intend to redeploy spectrum currently used for basic 2G services to support more advanced mobile Internet services on our 3G and 4G networks."
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The change is part of ongoing efforts to improve network performance, AT&T added. The telecom giant is facing "significant spectrum and capacity constraints" on its wireless network in certain markets due to greater demand for wireless service in the U.S., it said.
"Our capacity constraints could affect the quality of existing voice and data services and our ability to launch new, advanced wireless broadband services, unless we are able to obtain more spectrum."
AT&T said 12 percent of its contract wireless customers were using 2G handsets by the end of June, but that it will move them to more advanced networks, over the next five years. Whereas a growing number of its customers, including one-third of contract smartphone subscribers, use a 4G-capable device, the company added.
AT&T said a 4G network, which it is releasing across the U.S., enables faster speeds and shorter data transfer times, according to its website. Like other major cell phone carriers, most of the company's customers use phones with 3G technology, the Wall Street Journal reported.
A spokesman told the newspaper that it no longer sells 2G handsets to prepaid or contract customers.
AT&T did not immediately respond to requests for comment.
This story originally published on Mashable here.