AT&T Inc. and Verizon Communications Inc. are pursuing diverging broadband strategies as part of aggressive efforts to gain control of the market.

AT&T is investing heavily in deploying fiber to more homes in a bid to win fixed broadband customers. Verizon, meanwhile, is betting on its fixed-wireless home internet service.

These two strategies were readily apparent in the telcos' fourth-quarter 2021 earnings results.

AT&T continued to lead in fiber customer adds, gaining 271,000 fiber consumer lines in the last three months of 2021 and more than 1 million in the full year for the fourth consecutive year.

"In wired broadband, we have the fastest-growing fiber network and expect to capitalize on the expansion of our fiber footprint and accelerate subscriber growth," said AT&T CEO John Stankey.

Verizon, by contrast, added 51,000 Fios customers. While that figure pales in comparison to AT&T's adds, Fios Internet, Verizon's high-speed fiber offering, had its best year in net additions since 2014, tallying 360,000 Fios total net additions.

While AT&T is rapidly expanding its fiber customer base, Verizon is prioritizing its fixed wireless network in the creation of what will be a "state-of-the-art multipurpose network," combining 5G technology and fiber, according to Verizon CEO Hans Vestberg.

Verizon had 78,000 fixed wireless net additions in the fourth quarter, almost three times the number of wireline broadband net additions in the same period. Verizon's wireline broadband offerings include both fiber-based Fios and legacy copper-based DSL offerings.

Verizon expects to rapidly grow its fixed wireless subscriber base following the Jan. 19 launch of its 5G Ultra Wideband network to more than 90 million potential customers. The Ultra Wideband service relies on a combination of mid-band spectrum known as C-band and high-band spectrum known as millimeter wave. Mid-band spectrum is considered essential for 5G delivery, balancing speed and range.

"We believe that Verizon's fixed wireless access offering will drive the next leg of broadband growth, increasing our market share and reach," Vestberg said during Verizon's Jan. 25 earnings call.

While fiber tops fixed wireless in terms of reliability, the difference between fiber and wireless performance will become decreasingly significant as wireless speeds reach 100 Mbps and above, said Jeff Moore, principal of Wave7 Research, a wireless research company.

Verizon's 5G Ultra Wideband network offers typical download speeds of 90 Mbps to 170 Mbps and typical upload speeds of 15 Mbps to 30 Mbps. By comparison, fiber speeds generally range from 250 Mbps to 1000 Mbps, according to broadband comparison site BroadbandNow.

"Fiber is inherently a stronger technology, but as time goes by, this will matter less and less. At the end of the day, the most bandwidth-intensive aspect of data is video and 5G wireless is more than adequate for delivering this," Moore said.

For now, investors seem more concerned about dividends and the potential for slowing growth in the companies' wireless businesses. AT&T and Verizon each saw their stock prices dip in the wake of reporting earnings last week. AT&T's stock price was down 2.1% for the month to date as of Jan. 26, while Verizon shares were down 3.2%.