AT&T deployed a third-party rApp on its live production network in a demonstration of open radio access network (open RAN) capabilities in a brownfield environment.

The rApp was deployed in AT&T's existing brownfield networking using Ericsson’s service management and orchestration (SMO) platform over the O-RAN Alliance R1 interface. This allowed the rApp to communicate with the SMO layer using open, standardized APIs and highlighted the potential of open standards in disrupting closed, single-vendor self-organizing networks (SON).

Stéphane Téral, chief analyst at Téral Research, told SDxCentral that AT&T is “at the forefront” of centralized SON development, with the Ericsson partnership part of its 5G RAN and RAN intelligent controller (RIC) vision.

“Ericsson, long time open RAN nay-sayer, was brought in by AT&T in December 2023 to lead the complex, thorny, and risky task of migrating AT&T’s two SONs and in-house RIC onto its Intelligent Automation Platform while onboarding third-party rApps," Téral explained. “This is the world’s first non–real time RIC commercial deployment, which also confirms that open RAN in a brownfield network is real, works, and delivers."

These rApps are microservice-based applications operating in non-real time, in the case of rApps, and in near-real time in the case of xApps. These provide an operator with more control over their open RAN environments.

Behind the deployment

The rApp in question was developed by a third-party vendor and certified through Ericsson's Intelligent Automation Platform (EIAP). The app’s function and supplier were not disclosed, but typical rApp use cases include traffic steering, interference mitigation, and energy savings.

An AT&T spokesperson told SDxCentral the company evaluated “numerous potential SMO suppliers and based on the capabilities of the Ericsson platform, we felt the EIAP would help us meet our automation and cost saving goals for the future.”

AT&T also confirmed it is “now thinking more broadly to bring in more open RAN solutions” after the trial’s success.

A more open Ericsson?

Joe Madden, lead analyst at Mobile Experts, believes the news underlined Ericsson’s leading status in open RAN.

“It may surprise people to hear that Ericsson is the leading vendor in the commercialization of open RAN software," Madden said. "Ericsson resists some features of open RAN that don’t support their vision of high-performing networks. But they have established an ‘app store’ of open RAN optimization applications from more than 20 different developers.”

Madden – who also confirmed the deployment as a first – added: “The latest news is even more significant because Ericsson controls more than 40% of the global mobile network outside of China, so any applications developed for Ericsson networks have a large market potential.”

This potential may depend on open RAN’s acceptance in the market.

Dell’Oro Group recently reported that revenues related to the sale of open RAN equipment plunged in 2024, while complexity concerns have been raised about the offering concerning interoperability and performance.

There are also security concerns with open RAN, with Analysys Mason telling SDxCentral that an increased number of open interfaces can pose considerable security challenges.

Anders Vestergren, head of solution area network management at Ericsson, dismissed such concerns regarding the AT&T rApp deployment.

“AT&T follows a rigorous process to validate the reliability and performance of any application that interacts with its network," Vestergren said. “This application underwent extensive lab testing before being onboarded to the commercial network.”

Vestergren also touted Ericsson’s current openness to open standards, with the deployment showing “the real purpose of the ecosystem in action – bringing multiple parties together in one open system to deliver a result.”