Fujitsu late last year garnered significant attention as one of only two vendors mentioned by AT&T as part of its multibillion-dollar open radio access network (RAN) initiative. That announcement positioned Fujitsu ahead of much larger rivals in gaining a share of the lucrative open RAN space, but the vendor also knows that positioning will be more fluid than past infrastructure evolutions.

Greg Manganello, head of wireless and services solutions for Fujitsu Network Communications, told SDxCentral in an interview that the vendor was “very honored to be inside and mentioned” as part of AT&T’s “nice announcement.”

“AT&T had a nice announcement that we're very honored to be inside and mentioned, and there's other people mentioned because it's an ecosystem,” Manganello said. “It's just so interesting because the announcements of old were like, ‘we won this deal with these guys,’ but now what you're seeing is more complex announcements.”

AT&T’s announcement included the carrier signing a deal with Ericsson to be the base of an extensive multiyear, multi-billion-dollar open RAN deployment across the carrier’s nationwide network. Igal Elbaz, network CTO at AT&T, explained in a press briefing that the carrier plans to spend around $14 billion over the next five years to deploy open RAN equipment. The goal is to have 70% of its wireless network traffic flowing through its open RAN platform by the end of 2026.

Elbaz further explained that the move takes advantage of AT&T’s decade-long effort in driving SDN and virtualization into its network operations and further allows it to tap into a diverse vendor set to provide network equipment.

“The ability is needed to introduce multiple vendors both on the hardware and the software side, and an open management system,” Elbaz said. “I actually think that AT&T is really uniquely positioned to lead that scale transformation in terms of open RAN in the U.S. simply because of our track record in the introduction and deployment of openness and disaggregation in other parts of our network.”

But, to this point, AT&T has only named Ericsson and Fujitsu as vendors in the deal, to the consternation of those not named. Some of Ericsson’s rivals have questioned the true openness of its platforms and the ability for Ericsson to act as an overall systems integrator (SI) for this open RAN deployment.

Ericsson has repeatedly been ranked as one of the market’s largest RAN vendors, typically duking it out over top honors with China-based Huawei. Ericsson has also been aggressive in rolling out new RAN hardware and software components to further bolster that position.

However, Ericsson has been a much smaller player in the open RAN space, which instead has been dominated by the likes of Samsung, NEC and Fujitsu. All three of those vendors have extensive ongoing open RAN work with operators in Europe and Japan.

Rob Soni, VP of RAN technology at AT&T, did tell SDxCentral that the carrier’s decision was based on scale, which is why the operator is leaning heavily on long-time network partner Ericsson.

“They have 65% of the network,” Soni said of Ericsson’s current foothold into AT&T’s wireless network architecture. “They also have the scale to be able to accomplish and I think one of the challenges that we have with some of the newer non-incumbent RAN vendors is that they need a scale platform to build off of as opposed to building totally from scratch.”

While Fujitsu’s leadership in the open RAN space made it a more palatable choice, Manganello’s modesty is based on the amount of work the carrier and its vendor partners now have in front of them.

“We're so excited and honored to be in that announcement,” Manganello said. “But it's not like everything's done and we're shipping things. I think this is sort of like a direction and a collaboration, and we're going to offer our knowledge and our contribution, and then we're looking forward to the future.”

Fujitsu has gained significant knowledge from its ongoing work with operators like NTT DoCoMo, KDDI and Dish Network in the U.S. Manganello said these have all been collaborative efforts toward serving the operator.

Some of that knowledge will also come from Fujitsu’s past work on open standards in the optical networking space.

Manganello said Fujitsu got its open start in the optical networking market with open reconfigurable optical add-drop multiplexer (ROADM) technology. This included work with AT&T in that space.

“Working things out with multiple vendors for our customers, that’s really new and we brought that to the RAN side,” Manganello said.

That open ecosystem provided Fujitsu with important insight into how competing vendors can cooperate with each other toward fulfilling the needs of customers, especially when it came to integration challenges.

“We're competing, we're cooperating, but that's an old message of coopetition,” Manganello said. “The new message is it's really up close and personal, engineer to engineer, and I think that's great for our customers. Let’s make sure this works. Not just the sunny-day scenario. It’s the rainy-day scenario where all the engineering is. It's all about what if this happens, and these two other things also. The sunny-day scenario you can code up kind of quickly.”

Some of Fujitsu’s open future will also include leveraging artificial intelligence (AI) to boost the performance and efficiency of its open RAN work. The vendor late last year was able to inject its open RAN Virtuora Service Management and Orchestration (SMO) service with power-saving capabilities using AI.

This involved an rApp that uses traffic estimates powered by AI and machine learning (ML) to manage network capacity as needed. Fujitsu noted that a test of the system, which included AT&T in an advisory role, provided 20% power savings compared to legacy network management methods.

Manganello said this is providing the “right entry point” for operators looking to work with open RAN.

“We get a lot of attention,” Manganello said of that savings potential. “It’s like, ‘well come to my office very soon, let’s get on a call quickly.’ Except that’s only available on open RAN. The rApps are pulling in the interest of open RAN.”

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.

Analysts have noted the importance of this work as operators look to squeeze operating efficiencies from their 5G network investments. An ABI Research report indicated that while 5G equipment can be more power efficient than legacy 4G LTE equipment, network densification will increase the overall power draw.

“Despite 5G consuming less power than 4G per unit of traffic, the overall energy consumption is still much higher, driven by more power-thirsty radios and network densification,” ABI Research analyst Fei Liu wrote in the report. Liu added that whereas 5G infrastructure can be 90% more energy efficient than 4G LTE on a per-bit basis, a typical 5G base station also requires three times more energy to provide the same coverage as a 4G LTE network.

“5G energy consumption depends on radio configuration, hardware and traffic load; and over 70% of the consumed energy is in the [RAN]. A 5G RAN consumes up to 2.7 kilowatts of power with [64-transmit/64-receive] massive [multiple-input/multiple-output] configurations in a typical condition, whereas an LTE radio consumes about 0.8 kilowatts,” she wrote.

Manganello added that this level of control is only possible using AI.

“I think the days of human control are sunsetting,” Manganello said, “These are large multivariant problems and I'm not sure we can all humanly see the patterns.”