Ericsson is starting to embrace open radio access network (RAN) principles from a relatively safe social distance. The Swedish vendor said it will release Cloud RAN, software that virtualizes the compute piece of the RAN, during the fourth quarter of 2021. 

The move will allow for more automation and virtualized RAN, specifically the centralized unit and distributed unit, to run on commoditized x86-based hardware, according to Ericsson. 

The vendor, which has been more reticent than some of its major competitors to embrace efforts to separate hardware from software in the RAN, is now embarking on a long, multi-stage process to further develop that outcome. Ericsson expects this to be incremental, taking many years to materialize at a level of performance that can match or beat current traditional RAN frameworks, said Per Narvinger, the company’s head of product area networks. 

Many industry players are advocating for a mix-and-match approach to the RAN, and see virtualization as the first step, he said. “Rather than see or have a strong view of what happens further out in time, we see that we are taking major steps now going to an offering of a virtualized compute solution,” Narvinger explained.

Ericsson’s Cloud RAN software will be released in stages, beginning with 5G networks running in low-band spectrum using commercial off-the-shelf (COTS) hardware to virtualize the RAN. The vendor said its Cloud RAN DU and Cloud RAN CU also include new radio gateways to make existing remote radios compatible with the Cloud RAN software. It is also compatible with Ericsson’s dynamic spectrum sharing (DSS) software and will work on non-standalone (NSA) and standalone (SA) 5G deployments.

Narvinger claims that Cloud RAN “will be a foundation for openness in the industry, and then we will see how it evolves.” The vendor intends to eventually add support for mid-band spectrum, but those networks “become so computationally heavy that you need accelerators” and the industry is still developing or determining how accelerators might fit into the mix, he said, adding that this initial effort from Ericsson does not require accelerators. 

Millimeter-wave (mmWave) support will likely follow as well, he said, but that will be even further down the line. 

Ericsson’s slow or measured approach is a tacit recognition that it took many years for virtualization to occur in the network core. The vendor also recently cited a series of unresolved security challenges and shortcomings in open RAN.

Varying levels of openness are also being facilitated by the standards for 5G at large, including the separation of hardware and software, and the ability to assemble a 5G core from multiple vendors running on non-proprietary hardware, Narvinger said.  

“The next step or level of openness” falls under groups like the O-RAN Alliance, which is trying to push things much further, he said, adding that Ericsson is a member of the O-RAN Alliance and “driving some interfaces heavily” because it sees benefits for its customers.

Orchestration is one example of that, according to Narvinger. “If you start doing orchestration across different domains, across the core network, and transport, and RAN, there’s great benefits. So there we are really driving the development.” Ericsson isn’t making that commercially available now, “but of course our Cloud RAN is prepared for that,” he said.

However, there are other interfaces that Ericsson does not intend to fully open. “If you take the interface between the cloud compute piece and the radio, typically referred to as the fronthaul, we see that we have major advantages by keeping that to the Ericsson implementation rather than what is, for example, done in the [open RAN] space,” Narvinger explained.

“It’s not so much what is possible, it’s actually what is commercially viable” and when open RAN vendors can deliver “an implementation that actually competes with something that is purpose built,” proprietary and tightly integrated, he said. “If you just count what you get out of a COTS solution and a purpose-built one, you’re still going to get more out of a purpose-built one or you will have to invest in more servers or accelerators.”

Narvinger disputed the suggestion that Ericsson is coming to the open RAN party late, but rather framed it as a journey it plans to take with its customers as meaningful developments occur. “Many of our customers are still not even fully evaluating [open RAN],” he said. 

Ericsson has trials underway with some customers, but most operators haven’t even started looking at virtualization, let alone full open RAN, he added. As such, Ericsson is announcing Cloud RAN a year before it plans to make it commercially available in a bid to kickstart those conversations with operators.