Last week the U.S. Federal Communications Commission brought together a variety of Open RAN stakeholders for its Forum on 5G Open Radio Access Networks. While greenfield operators like DISH and Rakuten Mobile seemed steadfast in their conviction that Open RAN was ready to go today, representatives from AT&T and Verizon noted their excitement and work on disaggregated radio access network hardware and software, but also honed in on challenges to adoption.
Open RAN is a red hot topic in the telecom industry as proponents tout the ability to take cost out of RAN by moving from proprietary technology stacks to more flexible, multi-vendor kit. Telefónica, for instance, announced last week it’s looking to massively deploy Open RAN sites in the 2022-2025 timeframe; Global CTIO Enrique Blanco called the shift to commoditized hardware a “necessity.”
Another angle here is developing a U.S.-based vendor ecosystem that can be used to replace Huawei equipment domestically and foster competition against the Chinese giant globally.
AT&T’s Laurie Bigler, assistant vice president and tech staff member for access analytics and systems, pointed to trials of the Radio Intelligent Controller (RIC) the operator has conducted on its millimeter wave 5G network in New York as a proof point of the company’s interest, but also noted challenges around “ensuring the reliability, integrity and performance for our customers,” which she noted is not unique to Open RAN.
“O-RAN is still developing specifications at this time and some are further along,” she said. “Having specs alone does not guarantee interoperability or performance. We really see that integration is the biggest challenge ahead. You really don’t find the issues or gaps with the specs until you actually try to integrate two vendors’ equipment.”
In terms of how Open RAN fits into AT&T deployment plans, Bigler said she foresees a “gradual introduction of Open RAN into our existing network.”
Lori Fountain, director of network infrastructure planning with Verizon, made clear that Verizon is “a player in O-RAN as well as an early adopter,” but said incorporation of the emerging technology is “a journey. We’re kind of at the first step of that journey, which is the ability to mix and match baseband software with an open [radio unit] and we’re excited.”
She continued: “The challenge we see at Verizon is scale and maturity. We have a mature network here at Verizon and it’s not a greenfield network. We support O-RAN entirely and know it is the future. We will be adopting this critical architecture and in a timeframe that successfully allows the network to mature gracefully but, at the same time, protecting our customers.”
Fountain also discussed the role of Open RAN in supporting specific types of deployments, giving the example of in-building 5G. “We need to bring a variety of options to the space as the customer needs are varied. One solution doesn’t necessarily fit all. If you go into a customer’s warehouse and you want to put…a 5G radio there, that may not be what works in a hospital. Having more options and a variety of radio and baseband vendors from which to choose, it helps us customize our solutions for our customers and ultimately provide the correct solution with the best characteristics for that customer.”