AT&T might have turned down the volume a bit in terms of how loud it trumpets internal network innovation compared to some of its rivals, but that doesn’t mean it’s not making progress toward new technologies like 5G standalone (SA) core and open radio access networks (RAN).

Chris Sambar, EVP for technology at AT&T, during a keynote speech at this week’s Brooklyn 6G Summit said the carrier’s under-the-radar 5G SA network is in fact supporting a lot of new 5G customers and use cases. Specifically, he stated that the carrier’s 5G SA core was supporting all of AT&T’s fixed-wireless access (FWA) customers are using the 5G SA core, it’s supporting some of its connected car use cases, and all of the carrier’s Apple iPhone 15 devices are running on that advanced core.

AT&T not moving quickly on 5G standalone core

“I would say we are not moving as quickly as some of the other operators on the 5G standalone core, but we see the use cases that are coming, we understand when they're coming, so we're being very purposeful about getting there when we need to get there,” Sambar said. “No issues and we're pretty excited about that.”

AT&T’s self-proclaimed cautious approach to its 5G SA core is echoed by rival Verizon, which is also taking a methodical approach.

“We don’t see that there’s a huge need for me to move in that direction,” Joe Russo, EVP and president of Verizon’s global networks and technology business, recently told SDxCentral. “I have the capacity and coverage that our customers need, and I have the feature functionality that they can do what they need to do.”

However, as opposed to Sambar’s “no issues” commentary, Russo said that Verizon’s own testing of 5G SA has shown a need for the technology to improve.

“We’re not going to put technology in the network that steps us back from a reliability and performance perspective,” Russo said. “And I would say generally, based on the testing we’ve done, based on the work we’re doing trialing our standalone capabilities, we are not ready to put that out into the network.”

Russo specifically mentioned challenges with handling voice traffic on 5G voice-over-new-radio (VoNR) technology that can compare with its already established voice-over-LTE (VoLTE) network.

“We want to make sure it’s done right, so we’re doing a lot of testing with that right now,” Russo said. “We’re trying to make sure that we have that really at the standards of Verizon before we put it out.”

Russo is not alone with his 5G SA technology maturity concerns.

Analysys Mason noted that a recent operator survey found more than 50% of respondents “chose this as a critical barrier to their adoption of 5G SA. Reliability and performance are vital considerations, and any technology issues in the 5G core could cause service degradation over wide areas. This is particularly the case during migration phase, where operators face the most risk to service performance and can encounter issues relating the running of old and new cores together,” James Kirby, senior analyst at Analysys Mason, wrote.

Open RAN is moving, ‘I promise’

“I promise it is moving,” Sambar said of the carrier’s open RAN efforts. However, that movement is running into a scheduling issue, which Sambar referred to as a challenge in “aligned incentives.”

[Related: AT&T taps Ericsson for $14B open RAN plan]

This, Sambar explained, is the ongoing challenge in getting the broader RAN ecosystem to accept a new financial model.

“I think some people in the industry view it as you're trying to completely commoditize what we do,” Sambar said. “I don't think that's true.”

Sambar pointed to a Nokia presentation at the event that talked about using artificial intelligence (AI) to help the management of 6G networks.

“That's incredibly important, and we need to make sure that [research and development] machine keeps going,” Sambar said. “We're not just trying to bring everything down to a commodity but we're trying to open up innovation with [open RAN] and so getting the incentives aligned in the industry is going to be very important for that.”

Analysts have noted that financial alignment could take several years.

Mobile Experts recently released a report that forecast open RAN-related revenues peaked in 2022 at just over $2 billion; will dip slightly this year; and then drop to a $1.5 billion per year run rate between 2024 and 2026.

“I refer to the cycles of the telecom business as summertime and wintertime,” Joe Madden, lead analyst at Mobile Experts, told attendees at the recent Cable-Tec Expo 2023. “You just had the summer of 5G where we were deploying lots of base stations, everything was groovy. But now things are down. Earnings announcements are coming out and they’re on the negative side. The companies that are really betting big on open RAN, they’re going to have to survive the winter, three years of low revenue or maybe kind of the same as where they are right now, and then see growth later.”

Neville Ray, former president of technology at T-Mobile US, echoed that cyclical sentiment in an interview with SDxCentral earlier this year.

“For us, we didn’t go down on open RAN path when we made our big vendor decisions three years ago,” Ray said. “The pace and scale that we were moving on, features and capabilities we needed, the ecosystem just was not ready. And the O-RAN guys will tell you that.”

Those RAN decisions involved five-year contracts signed in early 2021 with Ericsson and Nokia to supply 5G RAN equipment for the carrier’s $40 billion network upgrade. Those vendors have lagged the broader ecosystem in commercializing open RAN equipment.

However, Ray did preface his comments by stating, “I think the ecosystem’s maturing.”

“We’ve made massive investments into single RAN in our network environment, and it’s not like we’re repeating that soon,” Ray said. “But clearly, we’re evaluating continually open RAN opportunities. We believe that the ecosystem will be stronger with open RAN. But there isn’t a deployment thing that T-Mobile US is doing now.”

Despite that timing challenge, Dell’Oro Group still expects open RAN equipment will account for as much as 10% of overall RAN revenues this year.