Your browser is not supported. Please update it.

20 September 2022

Verizon has deployed 8,000 vRAN sites with Samsung, not multivendor yet

Verizon has been working on various virtualized RAN (vRAN) architectures since its early deployments of 5G Cloud-RAN in some urban sites, and some enterprise roll-outs. In 5G, it has turned its attention towards more complex disaggregated designs with full cloud infrastructure and the potential to be multivendor (though so far, its publicly announced RAN partners have been the same as for its conventional RAN, notably Samsung).

But while the US operator’s commitment to, and definition of, Open RAN remain somewhat hazy, it has made significant progress with vRAN deployment. It said last week that it had built out more than 8,000 vRAN cell sites and aims to increase that number to 20,000 by the end of 2025.

Verizon currently has one major 5G vRAN equipment provider, outside of some enterprise or private network pilots – Samsung. The Korean supplier has been a 5G vendor to Verizon from the start of its roll-out, building on some expertise in millimeter wave radios, which the operator used for its first wave of 5G roll-out and for fixed wireless access (FWA). It gained an increased share in Verizon’s conventional 5G RAN at the expense of Nokia from 2019. And it sees the relatively level playing field created by migration to vRAN and Open RAN as an opportunity to increase its market position against Nokia and Ericsson.

Nokia has implemented some vRAN pilot sites with Verizon but now, Samsung is at the heart of the program. A Verizon spokesperson said: “The vRAN units cited in this release are our RAN equipment which is provided by Samsung.”

According to studies by Mobile Experts, Verizon is installing its virtualized distributed unit (vDU) equipment at cell sites using rugged enclosures, but without the air conditioning or extra power required to integrate edge compute too, as some telcos plan to do, in order to support 5G/edge applications. Verizon is advanced in its implementation of multi-access edge compute (MEC) so may add these capabilities later, but for now, its edge nodes are further back from the sites, often in former central offices.

The company said: “Verizon’s MEC is deployed in a rack next to its core network gear to enable the lowest possible latency. We are partnering with the top cloud partners, driving tighter network integration/differentiation through APIs. Verizon recently expanded its MEC ecosystem by bringing AWS Wavelength zones to Nashville and Tampa and now reaches 19 metro areas. This means that 75% of the US population is now within 150 miles of Verizon 5G Edge.”

The RAN’s virtualized central units (vCUs) are running on Verizon’s own telco cloud in its data centers. “Using a Verizon-owned and operated webscale platform, Verizon engineers have created a cloud-native architecture,” said the company. “Verizon’s telco cloud has been optimized for telco workloads, unique telco regulatory and performance requirements, and tighter integration with other operations systems.” The firm confirmed that the vCU software is also from Samsung, as well as the vDUs and radio units.

While Verizon expects vRAN architectures to increase its network flexibility, and the ability to allocate and re-allocate resources dynamically for different services or slices, it is also boosting performance in other ways, notably be harnessing an increased amount of the C-band spectrum it won in last year’s auction. It is starting to deploy 5G in 100 MHz of C-band in some markets, rather than the 60 MHz it has used to date. And it recently completed lab trials using 200 MHz of C-band airwaves, an approach it intends to commercialize “in the near future”.

“Imagine adding several more lanes to a highway,” said Adam Koeppe, SVP of technology and planning at Verizon in a statement. “The more lanes, the more cars can get on and off the interstate and the faster they can drive. In the same way, the more spectrum we open up on our network, the more data can move across our network faster and more efficiently.”

In terms of multivendor open networks, Verizon was sticking to the line it has drawn for the past few years – that virtualizing the network now, and disaggregating its hardware and software elements, will lay the foundations for introducing additional vendors when open interfaces and platforms are mature and integration is robust.

Earlier this year, Koeppe, told an investor conference that the operator might adopt Open RAN in part of its network this year, but “definitely” next year. That is a delay from an original timeline, shared by Koeppe in early 2021, when he said Open RAN shipments to Verizon would start later in 2021. He added that most equipment would support Open RAN by 2022.

However, he also said all this equipment would come from the operator’s existing 5G vendors – Ericsson, Samsung and Nokia – and since Ericsson does not support Open RAN, this raised questions over Verizon’s interpretation. It may be that the operator plans to insist on O-RAN fronthaul support from its existing vendors, but not much more than that, or it is developing its own interoperability mechanisms to cover kit from all three suppliers. Certainly, it seems that compliance with Open RAN specs (whether vanilla O-RAN, or Verizon’s own) is enough to qualify a network as ‘open’, rather than having to be multivendor from day one.

Analysts from Wall Street firm Cowen & Co met Koeppe in the summer and summarized their findings for clients, noting: “Verizon certainly sees an open architecture opportunity in the RAN, specifically between the baseband and the radio (Company A can run the baseband, Company B can run the radio functions), for greater competition, though more standards work needed on software development and interoperability is needed.”

In August 2021, Verizon reached a significant milestone when it completed a fully virtualized 5G data session, working with Samsung in its recently acquired C-band spectrum. This made Verizon the first US operator – and one of the first in the world – to have a full 5G macro vRAN, complete with Massive MIMO, commercially ready (though it cannot be activated until the first tranche of C-band spectrum is cleared for use later this year).

The combination of vRAN and Massive MIMO is an area where Samsung has made significant progress and it claims to have been the first vendor to support full interworking between vRAN and 64T64R antenna arrays. This appears to have been a major factor in winning its recent $6.64bn 5G deal with Verizon, which came largely at the expense of Nokia. Nokia has promised 5G vRAN with Massive MIMO for midband spectrum by the end of this year, however, while Ericsson, Verizon’s largest RAN supplier, will follow suit next year.

“We will extensively deploy virtualized Massive MIMO equipment across the whole of our network,” Verizon said. “We will deploy vRAN with Ericsson after it has been tested and meets Verizon’s requirements.”

Verizon and Samsung successfully completed the trial data session in three locations –

in Texas, Massachusetts and Connecticut – and said they “reached speeds commensurate with more traditional baseband-radio configurations”, according to Mike Kondratiuk, Verizon’s director of RAN planning. He told SDxCentral: “We’re very pleased to see the added benefits of virtualization with no significant impact to speed or throughput.”

Samsung’s 64T/64R Massive MIMO radios and vRAN software stack were deployed in coordination with Verizon’s virtualized core during the trial, but other vendors will also be part of the US operator’s vRAN architecture. “We continue to work with a wide variety of vendors for our orchestration efforts across the core and RAN,” Kondratiuk explained. “With the integration of the virtualization in the RAN, our entire architecture will reflect the move to Kubernetes and container-based cloud-native design.”

Last year Verizon claimed the world’s first fully virtualized 5G data session from core to RAN to edge, working with Samsung, Intel processors and FlexRAN reference framework, and Wind River’s Kubernetes and container-based middleware.

Verizon has already begun commercial roll-out of Samsung 5G vRAN in low band spectrum, and it has some Ericsson Massive MIMO in midbands, but these belong to an earlier generation of antennas that does not work with vRAN.

“Incorporating full, cloud-native virtualization, Massive MIMO and beamforming into our network design and deployment will result in so much more than our customers merely seeing a 5G icon on their devices. This is 5G service optimized for peak performance,” said Koeppe at the time. He said Verizon was “focused on commercializing an operationally sound Open RAN architecture”. He said the main barriers were resistance from some existing suppliers, the R&D burden that was placed on small suppliers, and the need for standardization of management interfaces and a structured approach to ongoing enhancements and updates.

He also warned: “There will be increasing complexity and integration costs associated with integrating different components at scale.” However, Verizon expects to deploy some Open RAN at the network edge in late 2021.

Back in September 2019, Nokia announced one of the world’s first 5G vRAN deployments, with Verizon and Intel in Dallas (though not Open RAN). At this time, Verizon had conducted vRAN trials, with all three of its 5G RAN suppliers (Nokia, Ericsson and Samsung), and had made some implementations, particularly in localized small cell networks and in pre-commercial 5G. The first trials, in the first quarter of 2018, took place in Oklahoma City, with the virtualized baseband functions running on Nokia’s AirScale cloud base station server, based on Intel’s Xeon processors and its FlexRAN reference architecture, which supports the RAN stack running on servers.

The architecture built on existing centralized, but non-virtualized, units which Verizon calls cRAN hubs.

Nicola Palmer, the operator’s chief network engineer, said at the end of 2018: “We have thousands of these cRAN hubs throughout the US. They’ve already been identified. They are built out and equipped. And we have been in the process of centralizing those baseband units.” She explained that, as a result, 15 to 50 centrally managed cells could work together, using LTE-Advanced features like remote electrical tilt (RET), which can point an antenna array toward high traffic areas during the day and then tilt them up at night to improve coverage.

The next step is to “do a lot more … The cRAN hubs become vRAN hubs, and now you can communicate across cRAN hubs. … You can scale horizontally instead of vertically.”

In 2019, Verizon had also started to virtualize some functions in Layer 3 of the network, within its own cloud architecture. This was not all about 5G, though it will go hand-in-hand with 5G NR roll-out as that progresses.

The USA gains 5G coverage:

There are nearly 419,000 cell sites across the USA, according to the newest figures from the country’s wireless industry body, CTIA.

“The nationwide roll-out of 5G happened twice as fast as 4G, providing the physical foundation for our 5G economy,” CTIA wrote in a new report. “More wireless infrastructure is a big part of that successful launch as key federal infrastructure siting reforms continue to pay dividends by easing barriers to deployment. By the end of 2021, there were 418,887 operational cell sites across the nation. And that doesn’t account for all the new 5G base stations added to existing cell sites.”

The report said that the US operators collectively built almost 70,000 new cell sites between 2019 and 2021, up from the 42,000 sites constructed in 2016 to 2018. A relexation of state and federal rules related to the construction of new cell sites was credited with the acceleration. “More cell sites enhance coverage, encouraging adoption and helping to close the digital divide,” CTIA said.