The top tier mobile network vendors are chasing one another to launch virtualized RAN (vRAN) platforms, with varying degrees of commitment to emerging open RAN specifications. The centralized architectures of the last wave of virtualized ‘Cloud-RAN’ products – which applied to 4G and merely implemented the higher layer network functions in software – are forgotten.
Open or not, the new wave of 5G vRANs seek to run some Layer 1 and 2 functions in virtual machines or containers, which means deploying high performance cloud infrastructure close to the cell site, in a virtualized distributed unit (vDU).
Nokia, Ericsson and Samsung have all announced major vRAN architectures in the past six months, while Huawei – once an exponent of first generation C-RAN – remains cautious this time around. Samsung launched its 5G vRAN last summer , and like Nokia, (but unlike Ericsson) it set out a roadmap to support O-RAN as it becomes commercialized, where the operator wants to do that.
Now Samsung, which won a $6.6bn portion of Verizon’s latest 5G contract last year, reportedly at Nokia’s expense, has announced that the US telco is to adopt its vRAN architecture. This is unlikely to include Samsung’s O-RAN implementations any time soon though – Verizon’s CTO, Kyle Malady, recently said that, while the operator supports the concept of open RAN, “there’s still a heck of a lot of work to be done with O-RAN … We’re not abandoning the old way of doing things.”
By giving such a major role to Samsung, Verizon is actually being more radical than many operators that have proffered full commitment to O-RAN, but for now at least, have chosen the big three to provide their 5G kit. The operator says that Samsung – which supplied millimeter wave 5G equipment in some regions for its fixed wireless and Ultra-Broadband services – is now providing its vRAN for lower band 5G roll-out, branded 5G Nationwide.
Verizon implemented a new wave of coverage expansion, using dynamic spectrum sharing in LTE bands, in December and now covers 230m people. The latest areas to gain access to 5G Nationwide were parts of New York state and New England – where Samsung vRAN is being deployed – as well as central Texas and Tulsa, Oklahoma.
Samsung has some disadvantages when it comes to supplying 4G or 5G networks to operators that need to integrate with legacy equipment, but it also has some upsides that come from having very limited installed base, and being able to experiment with new architectures without considering legacy. It is pushing vRAN, as well as O-RAN support, aggressively as differentiators, rather than responding reluctantly to operator pressure as more established vendors appear to be.
Verizon has a long history of adopting cutting edge RAN architectures in order to differentiate its performance, working closely with its vendors and being prepared to deploy something that goes beyond or outside the standards. It has been less vocal about its virtualization program than AT&T, but is similarly advanced in its thinking, especially when it comes to building out edge computing to support very distributed network functionality, that can enable demanding use cases for industrial customers.
However, it has been cautious in its comments about open RAN, and indeed, its key network drivers in the past have been about unique performance differentiation rather than price pressure and generic platforms. Malady said, in an interview with LightReading, that Verizon was “100% behind the idea, and that’s why we’re pushing it”, but went on to focus on the hurdles that lie ahead for large-scale deployment.
“It’s early days. I don’t see any reason why the technology can’t work, but there will be things carriers need to work out if they do adopt it,” he said. “And frankly, I don’t know if that whole O-RAN model will be for every carrier in the world, either.” Like all operators, Verizon will welcome a broader supply chain and greater choice of partners, but not at the expense of an optimally performing network – and Verizon’s bar for that may well be higher than that of most other telcos, while it also values its high degree of control and collaboration with its favored vendors.
Malady added: “We’re not abandoning the old way of doing things. This is the way we’ve done things. We’ve been doing it for a long time.”
The telco is clearly still in the evaluation phase. He went on: “We see the promise that O-RAN brings. So we’ve put resources against it … So, we’ll work at a pace that we think is appropriate. If we don’t see the benefits out of it, we’d probably change our minds. But at this point, I do see the possibility for bringing new entrepreneurs, new players into the ecosystem.”
T-Mobile USA’s CTO, Neville Ray, was also recently commenting on O-RAN, and pointing out that the operator has to do a lot more “heavy lifting” – which may be more alien to TMO, and its cost-sensitive approach, than Verizon. “Today, I buy a solution from an Ericsson or a Nokia or a Samsung; it’s warrantied. I have one neck to choke. If something goes wrong, I know where to go. In an O-RAN environment, you have to do a lot more heavy lifting as the operator,” Ray said recently, highlighting “unanswered questions around intellectual property, around R&D, around system integration”.