Verizon’s virtualization efforts are allowing the operator to use automation and orchestration for more rapid network updates, including its ongoing push to inject more speed and capacity into its 5G network.

Adam Koeppe, SVP of technology planning at Verizon, told SDxCentral that the carrier’s virtualized core work is now spreading out to its edge environments. This includes Verizon’s tens-of-thousands of cell sites and its growing edge locations.

This expansion is allowing the carrier to “push improvements and customer benefits – software updates and enhancements – much faster” and easier, which frees up its engineers to focus on other issues.

“You can constantly be testing improved software or features or bug fixes, whatever the case might be, in a replica of that production environment and then immediately push it out into production in a very agile way,” Koeppe said. “That's the part where traditional cloud computing intersects with a cloud-based network for telecommunications.”

This software push is also supported by a “high-level of orchestration and automation built on top of it.”

Verizon’s automation boost is provided by its virtualized radio access network (vRAN) work, that is rolling toward 20,000 commercial vRAN sites by 2025. Those sites allow Verizon to remotely send updates as opposed to having to physically provide those updates at each site.

“That's not to say we have to send a technician to every physical site and plug into a piece of equipment and software, we still do these things remotely,” Koeppe said of the differences between those vRAN sites and its legacy infrastructure. “But having orchestration and automation on top of your virtual network, that simply does not exist in the purely physical world. It's not so much the software running, it's what you can do on top of that when you have the virtual framework to do it on.”

Verizon virtualization and managing different vendors

Koeppe did note the carrier will have to differentiate its vRAN work between equipment supplied by its different vendors.

The carrier is initially relying exclusively on equipment provided by Samsung as part of a blockbuster deal signed in mid-2020, which saw Verizon bypass long-time vendor Nokia. Verizon is also planning to start layering in vRAN equipment from Ericsson.

“It's a little different only in the sense that when you take a feature that comes through the 3GPP standard, which is a vast majority of the features on the network, each supplier is going to have a slightly different coding take on that feature,” Koeppe said. “That capability, that's by design. 3GPP doesn't write code for the suppliers. These are the standards that the suppliers will develop code to so that their software or their hardware works according to that standard.”

Those “standards” do apply to all suppliers, but Koeppe added that each supplier is different in how they “translate that standard.”

“Each would have its own testing process because while they're very similar, there are some unique differences based on the supplier,” Koeppe said. “And obviously when you have mobility traffic across your network, there are scenarios where customers will go from a footprint provided by Samsung to a footprint provided by Ericsson and you want to ensure that those handoffs work effectively as well.”

Open RAN work ongoing higher in the vRAN stack

Those inter-vendor differences are also at play on the open RAN ecosystem, which is further up the vRAN stack. Koeppe said that it was still “early days” in open RAN but that the carrier was still “working down” that path.

“We're particularly focused on the interfaces between different functions on the radio access network,” Koeppe said of Verizon’s open RAN work. “We want to ensure that if a supplier makes a radio unit that's best in class, and I have distributed unit software from another supplier that's best in class, the interface between those two is common and open so that I can mix-and-match to best in class suppliers if they may be different.”

Koeppe’s sentiment was similar to that from T-Mobile US’ technology chief Neville Ray, who told SDxCentral at the recent MWC Barcelona 2023 event that the carrier continues to monitor the open RAN ecosystem and efforts around the O-RAN Alliance.

“We’re trying to understand, make sure the various issues that we’ve seen, and we’ve seen starting to mature through O-RAN, are getting resolved. And I think there’s progress,” Ray said. “I think we all know that will reduce over time. But there are some good, strong U.S. companies in the space, which I think is very healthy. I’m very pragmatic about what we do and how we do it. O-RAN timing didn’t align with what we did. But going forward, we’ll see where we go.”

Verizon 5G spectrum boost

Verizon’s most vocal spectrum-enhancing efforts are based on its C-band spectrum. The carrier is currently using an average of 60-megahertz of C-band spectrum for its 5G network, though it spent more than $45 billion to acquire an average of 160-megahertz of spectrum across the country.

“The use of that increasing spectrum portfolio is all done by software,” Koeppe explained. “We’re telling the cell sites, OK, I am now able to use 100 megahertz or 140 megahertz and the software that runs at that cell site gets updated remotely. And now we're transmitting higher frequency spectrum bandwidth to customers. That's a very efficient use of both forward-looking equipment, meaning equipment to transmit the full spectrum allocation, and using virtual infrastructure to provide very rapid updates as we get access to more spectrum in our pipeline.”

That spectrum access is set for a boost later this year.

Verizon, along with rivals AT&T, T-Mobile US, and U.S. Cellular, recently filed a letter with the Federal Communications Commission (FCC) stating they would limit the propagation of their cell towers transmitting C-band signals near many airports. This includes 188 larger airports and military bases around the country.

The move is tied to the proximity of the C-band spectrum to radar altimeters used by some aircraft. The C-band spectrum falls in the 3.7-3.98 GHz bands while the radar altimeters use spectrum in the 4.2-4.4 GHz bands.

However, older radar equipment sometimes operates outside of its assigned bands, which means operators beaming 5G signals near the top-end of the C-band could potentially interfere with the older radar equipment. A similar issue impacted Ligado Networks’ ability to use spectrum it controlled near the 1.5 GHz spectrum band due to potential interference with older GPS equipment.

With those issues hopefully resolved, operators will soon be able to gain more access to that mid-band spectrum to support their 5G efforts.

“Our ability to push improvements across this vast network as we deploy new spectrum, new solutions, new capabilities with the cloud platform, the RAN automation and orchestration, that is a distinct competitive advantage for us that translates directly to customer benefit,” Koeppe added.