Open RAN adoption challenges: Will the train turn back?

‘Unstoppable’, ‘Bullet Train Explosion’, ‘Runaway Train’, ‘Last Passenger’, and the home-grown wonder ‘The Burning Train’—all of these are movies centred around trains spiralling out of control. With a brake failure, a malfunctioning system, or a sudden rule about maintaining a minimum speed, chaos unfolds. Add in fire, a suicidal driver, a bomb, and an angry lover, and it makes for a quintessential train thriller.

What stands out in these films is the eventual solution—someone manages to decouple something. By that, we mean something heavy: a compartment, a machinery module, a cargo coach, or even a section of track. That is the cinematic breakthrough—the idea that even a fast-moving, complex, engineering-heavy system can be opened up and reconfigured. It is thrilling to discover that a running train can be decoupled. Jaw-dropping, indeed.

No wonder we were so excited about the very idea of Open RAN. As a concept, it was as thrilling and as new as taking out parts and joining new ones on a moving train. Is that not what telcos deal with as well? A moving train of network availability, new revenue goals, required speed of uptime, and the threat of low margins or network failure. The thrill was well-warranted.

It involved opening up the complex system known as the Radio Access Network (RAN). A RAN primarily comprises Central Units (CUs), Distributed Units (DUs), and Radio Units (RUs), which were, so far, proprietary and came from a single big vendor. When Open RAN took its first breath, it became a whirlwind of hope, as telco operators could now use different RAN equipment parts from various vendors.

This would help them escape vendor lock-ins, reduce capital expenditures, and avoid infrastructure headaches. With the promise of interoperability between different vendors, telcos could replace the legacy, proprietary interfaces between the Base Band Unit (BBU) and the Remote RU. With Virtual RAN (vRAN), they could virtualise the BU, running it as software and saving on hardware. There was also the new option of Cloud RAN that would allow them to galvanise the baseband functionality through the cloud.

Players like Mavenir, Parallel Wireless, and Altiostar ran ahead excitedly with the concept of multi-vendor ecosystem, modular RAN parts and flexibility. Just disaggregate RAN and Voila! You can do so much with all the flexibility, interoperability and elasticity that follows. Wait, let us rephrase that. You could do so much. Because the way things stand today, they stand. Stuck between ‘then’ and ‘the next’.

Open RAN investments accelerated at a torrid pace between 2019 and 2022 but declined by roughly USD 0.5 billion in 2023.

Despite initial trials, ambitious pilots, and some bold deployments, Open RAN, as analysed by many analysts and reports, has not yet opened up. If anything, we now have a new beast in the buzz—the single-vendor Open RAN. Yes, 80% of the projected USD 11 billion budget for Open RAN could move towards traditional incumbent vendors with pre-integrated, proprietary vRAN solutions, which boast some internal open interfaces. The multivendor form of Open RAN (estimated by Dell’Oro Group) would make up only 5–10% of the RAN market by 2028.

So, what went wrong? Why is the train still unstable?

Open RAN Promises: Early Momentum and Challenges

A report by STL Partners, Open RAN: What should telcos do, pointed out that Open RAN has the potential to drastically reduce the volume of physical kits that MNOs need to deploy and operate. Open RAN has also garnered significant interest in the market. Vodafone plans to deploy Open RAN in at least 2,600 rural locations in the UK by 2027.

Similarly, Rakuten Mobile ratified its alignment with the Open RAN Alliance, deploying the world’s first cloud-native 5G network with a multi-vendor approach (counting millions of customers on its Open RAN network in Japan). There have been avowed efforts by KDDI and SoftBank, and an extensive Open RAN deployment by NTT Docomo (NTT Docomo’s OREX SAI subsidiary is making global products).

However, the promise seems to be fizzling out. Mobile Experts dissected an Open RAN forecast that, after great success with Open RAN deployment in greenfield networks such as DISH and Rakuten, Open RAN deployment came to a halt in 2024. Dell’Oro Group also noted that Open RAN investments accelerated at a torrid pace between 2019 and 2022 but declined by roughly USD 0.5 billion in 2023.

Agnivesh Tripathy, Senior Analyst at Everest Group, echoes that sentiment. “Open RAN deployments have trailed expectations, with large-scale rollouts still limited to only tens of thousands of sites globally.”

He explains some reasons behind those plateaus and dips. “While lab-based validation has advanced significantly, gaps remain when translating results to live network environments, leading to discrepancies between controlled and real-world performance. Pilots are predominantly conducted in greenfield or low-traffic settings, making it challenging to accurately assess large-scale cost and performance benefits until broader commercial deployments occur.”

The market development has shown that Open RAN products have yet to make a dent in the classic market for radio access technology.

John Strand, CEO of Strand Consult, has conducted numerous studies examining the reality of Open RAN. He calls a spade a spade and RAN as he sees it. “On Open RAN, there has been considerable discussion and some misconceptions in the market. The Open RAN narrative is potent but reflects more myth than reality. The idea is that open-source software and its components can replace patented, standardised hardware and technology. We welcome disruption and competition. Still, the market development has shown that Open RAN products have yet to make a dent in the classic market for radio access technology.”

To put it very simply, Open RAN has not delivered what the people behind Open RAN promised, Strand says it without gilding anything. “It is a technical and commercial disaster that in 2024, it lost market share, despite Open RAN’s market share being extremely limited. Operators do not want to increase the complexity of their network, and certainly not by bringing a lot of small producers into the network, producers who have limited resources.”

David Martin, Senior Analyst and Telco Cloud Lead, STL Partners, also affirms that it is fair to say that Open RAN has not lived up to its early expectations. “We have not seen the volume of deployments that we expected, and many of the current roll-outs are based on single-vendor vRAN. The vRAN platforms of companies like Ericsson, Nokia, and Samsung have moved significantly in the direction of Open RAN further than many expected. So, what we are getting now is a form of ‘hybrid RAN’: part open and part proprietary, part cloud-native and part appliance-based.”

The vision is to utilise Open RAN to lower the cost and complexity of RAN networks and, of course, Private Networks, remarks Ken Sandfeld, CEO and Co-founder of Revells. “For Revells, we have partnered with Intel as well as LG to bring Open RAN for PWN, both unlicensed and licensed, into the market.”

Rising Resistance: Why Open RAN is Slowing

There could be many reasons for this Bungee-dip. Being compatible with Open RAN does not necessarily make a vendor open to Open RAN. And telco enterprises may still be okay with it as long as they can use the ‘choice-card’ to flex their negotiating muscles at the table or utilise some features or innovations that a new vendor can add, while maintaining the ‘status quo’ of a big vendor RAN setup. Yes, status quo. As much as we rephrase it, it is there, haunting RAN. That is the paradox emerging most acutely in the few and far between Open RAN progress — the phenomenon known as single-vendor Open RAN.

“The integration of disparate vendor components frequently offsets anticipated operational savings and introduces heightened security and management challenges. As a result, Open RAN is most often deployed alongside as a supportive role for a primary and single vendor solutions to fulfil specialised or one-off requirements,” Tripathy elucidates.

Open RAN has created interoperability and flexibility, reckons Sandfeld. “In the eyes of an MNO, it has not realised the lower costs or more flexibility.” He opines that because they are 100% tied to their OEM vendor, adding third-party products is more of a hassle than it is worth. “For in-building, we are on the cusp of a huge shift from connecting BTS equipment to connecting Open RAN connections to the carriers’ core for the DAS. This is very clear in the market, and the NTIA NOFO is even funding most of these capabilities.”

Strand Consult’s concern is that some operators, including Vodafone and Deutsche Telekom, have capitalised on the Open RAN narrative as a policy argument to delay their rip and replacement of equipment from Chinese vendors like Huawei and ZTE. Strand contends, “They curry favour with the US government by making minor Open RAN purchases (helping to make a favourable US-policy headline) while the corpus of their networks remains Chinese, undermining the security for Americans and Europeans and the larger US defence goals. Strand Consult has documented this in its reports and research notes.”

Pankaj Kitchlu, Systems Engineering Director for India and SAARC at Juniper Networks, notes that many operators remain hesitant to fully adopt multi-vendor environments, primarily due to concerns about ensuring network performance and reliability. “Despite these hurdles, the Open RAN ecosystem is growing, especially in markets like Europe and parts of Asia where regulatory pressures and cost optimisation are pushing operators toward more open architectures. At Juniper, we are committed to advancing Open RAN through our open and interoperable RAN Intelligent Controller (RIC) platform.”

Many operators remain hesitant to fully adopt multi-vendor environments, primarily due to concerns about ensuring network performance and reliability.

There is also significant turbulence occurring at the hardware level with AI Silicon and RAN compute. Just think of how a new Nvidia computer, called ARC-1, now packs all the baseband hardware and software a telco’s 5G network needs. With network outage prediction capabilities, to top it all off. Imagine what happens to large single-vendor handshakes with silicon players at Layers 1 and 2 if such advancements reach the towers.

Ask Tripathy, and he points out how AI-silicon initiatives are targeting chips tailored to AI-driven RAN tasks. “Leading semiconductor firms are developing both hardware and software stacks optimised for Open RAN AI workloads, while traditional vendors like Ericsson and Nokia are establishing in-house chip design teams, broadening the scope for AI-silicon solutions in Open RAN environments.”

Regarding new avatars like vRAN and AI-RAN, there is more happening with the anatomy and hardware of RAN than we could have imagined just a few years ago. vRAN is accelerating due to higher-performance silicon and optimised software stacks, Sandfeld tells. “AI for RAN is happening now, and it will have huge impacts on the performance of Open RAN. The same silicon at the edge will process the local AI as well as the vRAN.”

There is a lot that is enveloping Open RAN. Operational complexity and lack of intent on the one hand. On the other hand, support or conflict from new software and hardware disruptions. That explains why the train is still monolithic and disoriented, in a way.

Open RAN: More than a Tech Conversation

Is Open RAN only a technology debate? No.

Generalised adoption depends on more than just pure technological capabilities. It also involves the economics, operational, and organisational transformation at telcos, integration across open RAN and legacy RAN (as the majority of deployments are brownfield), 5G adoption and use cases, and, increasingly, the geopolitics, Martin avers.

Open RAN is not a dud as an idea. In fact, as Tripathy highlights, it delivers cost-optimisation potential and innovation acceleration, but it has yet to overcome primary challenges. “There is integration complexity. Multiple interfaces must interoperate and adhere to evolving standards, requiring extensive testing and specialist integration services. There is also the issue of Operational Overheads. Heterogeneous, software-centric networks demand new DevOps skills and continuous validation of multi-vendor components. Also, Open RAN vendors lack the global operations footprint, end-to-end SLAs and turnkey support offered by incumbents like Ericsson or Nokia.”

The industry has made significant strides in developing and testing frameworks and specifications, with the O-RAN Alliance playing a central role in setting interoperability standards. Kitchlu comments, “Multi-vendor collaborations are increasing, and more pilots are demonstrating the real-world potential of Open RAN. However, challenges remain in terms of scaling these pilots into production environments and ensuring that the performance does not degrade as networks grow.”

“Multi-vendor collaboration has been demonstrated in high-profile cases (e.g., Rakuten, Vodafone), yet the ongoing operational complexity still necessitates specialised integration services.” Tripathy seconds that argument.

Open RAN is not a dud as an idea. In fact, it delivers cost-optimisation potential and innovation acceleration, but it has yet to overcome primary challenges. 

No matter what, Open RAN did change the basis on which the industry expects RAN to be delivered, says an optimistic Martin. “The idea that RAN should continue to be purely appliance-based and single-vendor forever is no longer tenable. And the operators that are deploying vRAN are making sure that it incorporates open RAN interfaces, so that the benefits of open RAN can be added on over time, e.g. the use of multi-vendor radios, openness to third-party orchestrators or RICs, separation of RAN software and the underlying cloud platform and compute, and enabling portability across different cloud platforms and multi-vendor interchangeability of components.”

That said, Martin stresses that the industry needs greater supply-chain diversity for the RAN. It cannot rely solely on three dominant vendors—Ericsson, Nokia, and Huawei—to supply every single component of the RAN technology stack. From a purely technological standpoint, open RAN principles remain a valid blueprint for introducing this innovation, and it is evident that the supply chain has significantly diversified, encompassing silicon, computer hardware, cloud platforms, RAN software, radio, SMO, RIC, rApps, and xApps. He explains that many of the integration and performance challenges have been addressed by testing, PoCs, trials, and ecosystem collaborations.

Sandfeld adds, “The vendors in the market have stepped up big time. Although we still have a long way to go, the pilots, POCs, etc., have proven that things work just fine. The caveat: it is not ‘plug and play’. There are still months of testing needed to connect different vendors’ products.”

For Private Wireless, the benefits of Open RAN are just beginning to take hold. Sandfeld shares a glimpse. “Open RAN-based products offer some flexibility in buying from multiple vendors, but currently, that is not what is driving things. What is driving this is the advent of new entrants in the PWN market, who are developing solutions for the Open RAN standard, making their solutions more open to an ecosystem. ORUs seem to be the number one product to go to the ecosystem for.”

A January 2025 Dell’Oro Group report unravels that regional 5G coverage imbalances, slower data traffic growth, and monetisation challenges are weighing on the market. There was an intense 5G acceleration phase from 2017 to 2021, but RAN investments tapered off in 2023 and 2024. Its analysts argue that RAN revenue streams from private wireless and FWA, taken together with MBB-based capacity growth, are insufficient to offset slower MBB coverage-based capital expenditures.

There are issues with current network utilisation levels and data traffic trends in more advanced markets, as well as doubts about the timing of capacity upgrades. The report also suggests that 5G-Advanced is unlikely to drive another major capital expenditure cycle. Instead, operators will gradually transition their spending from 5G to 5G-Advanced within their confined capital expenditure budgets. Additionally, 5G NR, FWA, mmWave, Open RAN, vRAN, private wireless, and small cells are expected to be the RAN segments that will experience the most growth over the next five years.

Probably, broader adoption will take place in the ‘6G era’, whatever that may look like, Martin feels. “In other words, open RAN missed the wave of 5G RAN roll-outs; but 6G will be cloud-native and open RAN-native from the outset, with a much greater role for AI in addressing the integration and performance challenges.”

Open RAN is stillborn, and Strand also maintains his scepticism and reality-check lens when asked about its future possibilities.

Open RAN has already delivered a radical change in assumptions. Still, adoption will be generalised only in the ‘6G decade’, Martin captures it, and aptly concludes the discussion, at least for now.

Well! That is how things look today.

What happens next – would the single-vendor Open RAN continue to be the doppelganger of the RAN that we wanted to change? Would a 6G capital expenditure cycle accelerate Open RAN? Would the very idea of RAN be obsolete as AI and silicon break new ceilings? Would even telcos – as we know them- be around?

Who needs a train-wreck movie when you can watch what is happening with RAN! Grab that popcorn and chew over these questions. Sit by an ‘open’ train window, if you can. The view is better because it is always in motion and constantly changing.