Verizon's latest DAS deployment isn’t as lame as it sounds

Does deploying an open radio access network (RAN) distributed antenna system (DAS) make you a leader in O-RAN innovation?

That was the claim Verizon made when it announced that it had deployed the first-ever interoperable multi-vendor open RAN DAS configurations at the University of Texas Moody Center and the Austin Convention Center.

What’s the big deal about deploying a DAS using open RAN? Distributed antenna systems have been used for years to beef up cell phone signaling in and around campuses and stadiums. They’re installed in convention centers and concert venues all over the country. They’re expensive, yes, but they’re routinely used by all the major U.S. carriers.

Verizon claims these DAS installations in Austin, Texas, are special because they’re the first DAS commercially deployed in the Verizon network using O-RAN interfaces with various components from different vendors. Samsung is providing its virtual distributed units (vDU) with an O-RAN interface to a CommScope DAS.

“DAS have a lot of coordination of access points (antennas throughout the building leading into a headroom for transport and base bands, etc.) They also integrate with the facility, so there are a lot of options for a variety of vendors and providers. That makes it a great opportunity for interoperability,” a Verizon spokesperson told Fierce.

These DAS implementations – which use C-band spectrum – are Verizon owned and other carriers won't be using them. Verizon is planning to do more DAS deployments using open RAN but isn’t saying exactly where, according to the spokesperson.

Lower DAS costs

What this kind of configuration likely means for Verizon is lower DAS costs, said Earl Lum, president of EJL Wireless Research. “It probably will save them money, and it’ll save them a lot of space,” depending on how many sectors are needed to support it, he said.

But it’s not a wide-area deployment of open RAN. “It is a self-contained sandbox, so if you blow it up, no one knows. It doesn’t impact the outside world or the macro. If you’re going to do a test, you’d rather blow up a box that no one’s going to see than blow up half of Dallas where everyone will know,” Lum said.

“It sounds lame, but there’s a reason why they did it – because it’s safe and it lowers the risk,” he said. “This is a cheaper way to do it.”

Verizon’s DAS installations are a small percentage of its overall capex for its wireless network. In that regard, an open RAN DAS looks rather insignificant.

However, “I think where it’s significant is it shows that open RAN architectures and solutions can be provided throughout the entire toolbox that’s at an operator’s disposal,” Recon Analytics analyst Daryl Schoolar told Fierce. “It’s not just small cells or macro networks. It’s DAS. Being able to do DAS as part of open RAN simplifies the service management and orchestration.”

And it’s important to remember that while Verizon has been quieter than AT&T about its overall open RAN ambitions, it’s no slouch. Earlier this year, Verizon announced that it had deployed more than 130,000 O-RAN capable radios as part of a move to open RAN. Last month Verizon named Santiago “Yago” Tenorio as its chief technology officer. Tenorio is a recognized expert in open RAN, having architected Vodafone’s open RAN network and former chairman of the Telecom Infra Project (TIP).

Two-vendor DAS

One of the early promises of open RAN was it would create more vendors in the RAN ecosystem and take out the vendor lock-in that Ericsson and Nokia enjoyed. With myriad vendors, operators could create a more competitive pricing environment and mix and match equipment.

But some smaller vendors that participated in the early days of open RAN ended up scaling back, and more operators appear to be going with a single lead vendor rather than multiple smaller ones. AT&T is one example, where Ericsson is leading its open RAN deployment, although the operator has talked about a “multi-vendor” strategy.

In Verizon’s case, Samsung and CommScope are the vendors, making it more than a single-vendor deployment, but it’s still not a truly multi-vendor DAS, noted Senza Fili President Monica Paolini.

“I see no problem with single-vendor or two-vendor open RAN because they are the first step in the open RAN direction. And even with multi-vendor RANs, I do not expect a large number of RU, CU and DU vendors in the same network. Even if the interoperability is there, the more vendors you have, the more complex the network is, so you want to find the right tradeoff and avoid having more vendors than you need,” Paolini said.

Schoolar agreed that the use of multiple vendors isn’t mandatory for an operator to call something “open RAN,” so long as it complies with the open RAN specifications. The industry might have aspired to have multiple vendors, but that’s not happening at this stage of the game.

As with a lot of things, aspirational ideals don’t always end up in the final product. “There are PowerPoints in the early stages, but the market realities are different,” he said.