The RAN presents the biggest challenges for cloudification

NEW ORLEANS — Cloud is a question of when not if for mobile network operators, according to speakers at a Connect (X) panel this week entitled "Surviving the Cloud’s Disruption to the Telco Business Model."

“Operators know [cloud] is the end game, and if you don’t do it you’ll die,” said analyst Stéphane Téral of Téral Research. “They are relying more and more on AWS and Azure, but at the end of the day you may see some of them do their own clouds.”

Despite moves by AT&T and Dish Network to transfer parts of their networks to public cloud platforms, this group does not expect hyperscale cloud providers to subsume mobile networks anytime soon.

“The clouds thought they were in this incredible position where telcos would bring their entire network to the cloud,” said Vapor IO founder and CEO Cole Crawford. “That has slowed down. Now telcos want cloud to bring its thing into the RAN.”

“This move to cloud native architecture is kind of inevitable,” explained Alok Shah, VP, networks strategy, business development and marketing at Samsung. “But there are challenges in telecom related to performance, reliability and security.” Shah predicted it will be a number of years before telcos automatically roll out new services in the cloud, and said that when it happens it might be a telco cloud rather than a public cloud.

The big challenge is bringing cloud infrastructure into the radio access network, the panelists agreed. Shah noted that “the radio unit can never be software,” but said other parts of the RAN can be virtualized and can run in a cloud environment. He noted Dish runs its open RAN Centralized Units on AWS infrastructure.

But for operators with legacy network assets, transitioning the RAN to a public cloud architecture could be very difficult, the panelists said. Crawford noted the high cost of transitioning traditional telco data centers. He said it would also be costly for public cloud providers to build extensive new infrastructure to support radio access networks, because of zoning and permitting.

Towers are often named as the logical location for edge data centers that can support vRAN and other cloud-based workloads. The panelists agreed that tower real estate will hold its value, but they don't expect it to offer investors the same opportunities as larger, dedicated data center sites. 

“The economies of scale do not sit on Crown Castle or American Tower or SBAC land,” said Crawford. “You do not have enough return there.” His company Vapor IO deploys micro data centers at the bases of cell towers and at other urban locations.

Open RAN

The panelists agreed that cloud-based RAN architectures will go hand-in-hand with open RAN. Shah said that when operators can physically separate elements of the RAN they will be able to support more use cases. Separate elements with open interfaces enable vendor diversity, and Shah said Samsung is already involved in several multi-vendor RAN deployments around the world. “It is not plug and play by any means but it is feasible at this point,” Shah said.

“Brownfield open RAN is hard is not just because of the infrastructure transformation but also the skill set requirements,” he said. “Operators need people who understand containers and Kubernetes and micro services.”

Crawford described an open RAN system his company has deployed with a “self-healing” Centralized Unit, Distributed Unit and Radio Unit. He declined to answer a question about how far apart the elements are, but said the fronthaul latency is 60 microseconds.