AT&T, Verizon likely need C-band before activating 5G SA cores: analyst

A new report from Dell’Oro Group says the slow deployments of 5G Standalone (SA) networks is dampening mobile core network growth. The analysts forecast a 5-year mobile core network compound annual growth rate of 3%.

“The cumulative revenue forecast for the period 2022 to 2026 is over $50 billion. The overall revenues and the CAGR have been dampened by the muted uptake in 5G SA networks,” said Dave Bolan, research director at Dell’Oro Group.

In the U.S. T-Mobile is the only carrier that has activated a 5G SA network core. Why haven’t AT&T and Verizon done the same?

Speaking with Fierce, Bolan said, “In the case of AT&T and Verizon they needed the bandwidth of the C-band.”

Both carriers are in the process of deploying their newly acquired C-band spectrum. But in the meantime, they really need their 4G networks to work in conjunction with their 5G networks to provide enough throughput.

RELATED:  Verizon, AT&T kick off C-band amid aviation overhang

“CSPs have three choices for offering 5G: Dynamic spectrum sharing, 5G non-standalone and 5G SA,” said Bolan. “Only 5G SA requires the new 5G core, and many CSPs seem content for the time being to stick with DSS and 5G NSA.”

In addition to the need for more mid-band spectrum to support their 5G networks, AT&T is also transitioning its existing 5G mobile core network to Microsoft Azure’s hybrid cloud.

RELATED: How’s 5G standalone doing in the U.S.?

So it’s unclear when Verizon and AT&T may be ready to activate their 5G SA cores.

Benefits of 5G SA

Around the world, there have been only 19 5G SA network deployments to date. Bolan provides the complete list of carriers offering 5G SA, in a recent blog

With the 5G non-standalone, consumers get the downlink speeds of the combined 4G/5G radios, but the uplink is only that of the 4G radios. With 5G SA, consumers get the 5G speeds of both the downlink and the uplink. Other advantages of 5G SA include the ability to offer network slicing, to do time-sensitive networking, and to use some new 3GPP standards for edge computing.

Bolan said, “Network slicing is happening all over China. China Mobile has like 500 edge sites and is doing network slicing for all these enterprise applications out there. The standard is pretty mature.”

T-Mobile hasn’t said whether it’s offering network slices from its 5G SA network. The company also has not said how its 5G SA core works with the earlier generations of mobile technology in its network.

“If you’re on a 5G SA cell site, there’s no LTE involved,” said Bolan. He said T-Mobile talked quite a lot about separating the control and user planes in its network. So, he speculates that they have made their 2G, 3G and 4G cores backwards compatible with their 5G SA core. “I think it’s probably a converged core,” he said, meaning that they probably route traffic from their older cores into their new 5G SA core, so they only have one core to operate.