Open radio access network (RAN) criticism? “We’ve heard enough of it,” Rakuten Mobile CTO Tareq Amin said during the Open RAN Policy Coalition’s Quad Open RAN Forum. 

While the benefits of cloud are broadly recognized and agreed upon, “we always, in telecom, put ourselves into this constraint that if you go outside of a predefined box you’re taking risks that are not acceptable,” he said.

“The one value that nobody could argue about is that we are living in a software world. We’re living in a world that is definitely dominated by the advantage that cloud could bring. We’re living in a world in which artificial intelligence (AI) and machine learning is going to take a pretty front stage and center to what we do every day in our business.”

Amin and executives from Microsoft and VMware addressed other points of criticism and complexity that, while valid in their view, are also unavoidable. 

Open RAN does increase complexity insofar as it relies on new protocols, specifically open interfaces that allow network operators to mix and match hardware and software from different vendors. The introduction of more vendors also, by extension, creates a larger attack surface for security threats and intrusion.

“Yes, it increases the threat surface. It also increases the tools you have to deal with that. And the threat surface increase is inevitable given where people want to go with the technology,” Microsoft’s VP of 5G strategy Shawn Hakl said. 

“If you just use open RAN to solve the same problem you’re solving for today, that would be one level of argument to say that you’re shifting from a hardware based approach to a software based approach with white boxes, but that’s not what the goal is,” he said. 

The rise of private networks and a massive deployment of small cells for network infill and capacity expansion, including millimeter-wave (mmWave) networks, is already underway, adding complexity to network management and deployment, Hakl explained. “You’re already putting RAN in more places in larger volumes.”

This pressure to expand RAN to more places and functions necessitates more agile architecture, he argued. Open interfaces allow operators to deploy and manage “a series of well defined, discrete elements with well-defined interfaces,” and tools can be plugged into that architecture for automation to protect and defend against attacks, he added. 

Open RAN “is a better alternative than some sort of a replication of a massive black box in places it wasn’t meant to go,” Hakl said. 

Mobile network operators can also implement zero-trust security, and network segmentation through virtualization and SDN to isolate and address security issues, VMware President Sumit Dhawan said. These technologies are available now and an open environment is the only path by which operators can deploy them, he argued. 

Concerns about increasing the number of appliances in a network topology may have been valid five to 10 years ago, but no more, Dhawan said. As evidenced by advancements in the cloud, “all of these technologies have matured and are ready to be rolled out in the RAN architectures as well,” he said. 

Dhawan also claimed that open RAN will pave the way for what he called “digital equity” by bringing modern wireless connectivity to communities that don’t have access or lack access to broadband infrastructure. 

Software remains the most valuable asset in these open RAN aspirations, but none of it is fully meeting the mark, Amin said during a group chat with analysts and press last month. “The underlying software architecture is absolutely flawed. It needs to evolve” to support automatic elasticity, healing, and resiliency in cloud-based networks, he said.

The benefits are abundant now, but ripe for significant improvement, according to Amin.

“We are still scratching the surface of what is possible, largely because the software architecture and the software fabric allows us to do an unbelievable number of software upgrades that are not possible with traditional solutions. It just doesn’t work,” Amin said. 

Rakuten Mobile, the first greenfield operator to deploy a fully virtualized open RAN at scale, currently installs about 300 software packages per day, he said, adding that other networks typically get software upgrades every six to 12 months. 

This push into software-driven RAN architecture is no longer up for debate, according to Amin. “Now it is the responsibility of the industry as a whole to really push the architecture, address the gaps.”

These changes aren’t easy, but they are doable and worthwhile, he said. “I think the problem will get much easier as standardization on all these interfaces becomes available.”