With the advent of 5G and the Internet of Things (IoT), the pressure on wireless networks is growing exponentially. As more end users join the network, the pressure to find fast and cost-effective RAN (radio access network) solutions is also growing.
In a traditional RAN, operators deploy networks using fully integrated cell sites, where the radios, hardware and software are provided by a single supplier as a closed, proprietary solution and the software-driven functionality is tightly integrated inside the hardware. Making any upgrades or changes to the wireless network, even seemingly minor ones, requires replacing physical hardware throughout the network - a costly, manual, and time-consuming process. Moreover, the proprietary nature of the system locks operators into a single vendor relationship rather than being able to swap out parts to take advantage of newer technologies or cost savings.
Open RAN can provide a fast and cost-effective way for operators to expand networks and meet the growing demand for connectivity, including the newer 5G capabilities. Deploying a purpose-built open RAN solution in the cloud can benefit operators in many ways.
The open RAN difference
To put it simply, open RAN defines a new set of technical specifications for hardware and software within the radio system. Those specifications are driven by two key concepts: virtualization and openness.
Virtual RAN does two very important things: it separates software from hardware and it moves computing from purpose-built, location-specific hardware to the cloud. This programmable RAN infrastructure, built with low-cost, general-purpose hardware means operators can use one virtualized baseband unit to support multiple radios instead of needing a proprietary, physical unit at every cell site. Virtualization also means operators can introduce and administer software-based RAN services without being forced to replace the underlying hardware.
Open RAN takes virtualization one step further. It not only separates software from hardware infrastructure, but it also replaces the proprietary communication interfaces between the centralized unit (CU), the distributed unit (DU), and the radio units (RUs) with open, standards-based interfaces. This enables operators to source radio and baseband hardware and software components from different vendors, choosing the best on offer to create powerful, vendor-agnostic systems.
Other benefits of open RAN
Total cost of ownership - The flexibility to choose hardware and eliminate vendor lock-in means lower cost of acquiring the RAN components. In addition, the cloud-native basis of open RAN means operators can leverage network automation and intelligent radio resource control to reduce the cost of upgrades and maintenance while reducing the complexity of day-to-day operation.
Future proofing - Virtual architectures can future-proof investments in the physical network. Operators can use software to upgrade RAN features and functionality on the same physical infrastructure to keep pace with changing market conditions instead of having to rip out and replace whole physical systems.
Faster innovation - Instead of having to replace both hardware and software to introduce new features and functions, operators can perform software updates on cloud-based installations, massively shortening release cycles for both new features and upgrades. Remote management also removes the need to send out technicians for onsite integrations, further reducing the time, effort, and cost of launching new products and services.
Better customer experience - Open RAN offers operators additional opportunities to evolve from merely providing commoditized “dumb pipe” connectivity to delivering customized experiences for different types of users. For instance, operators could offer their manufacturing customers an ultra-reliable network optimized for near–real-time response for supporting factory robotics and automation. An energy producer might prefer a pervasive low-power wide-area network for widespread monitoring of assets such as gas pipelines or oil rigs.
Challenges of open RAN
Initial deployments of open RAN at cell sites and data centers are starting to see challenges emerge in real-world situations. While greenfield open RAN can start with a clean slate and utilize open software and hardware, brownfield deployments must often deal with hardware solutions that have evolved over time and are only now figuring out how to support virtual and cloud deployments. These solutions, however, are mostly not open or optimized, causing implementation issues that must be resolved as operators work to integrate open RAN into existing network infrastructure.
The open RAN ecosystem has just begun, compared to older technologies and standards. One concern is that manufacturing capability for open RAN hardware isn’t fully in place. Telcos may be wary of fully committing to open RAN if they can’t easily procure the necessary hardware from a solid supply chain. Also, until hardware manufacturing scales up, it may not be as economical as the current technologies, and that cost differential may discourage operators from moving to open RAN.
Finally, some operators are concerned that open RAN may fall short in more challenging deployment scenarios. More work is needed by alliance groups and partners to ensure that open RAN can work anywhere in the network, across 3G and 4G as well as in the newer 5G implementations. That said, Operators like Vodafone are moving forward with open RAN as a way to extend 4G and 5G coverage as in rural areas.
Johan Wibergh, Vodafone Chief Technology Officer, said: “Open RAN provides huge advantages for customers. Our network will become highly programmable and automated meaning we can release new features simultaneously across multiple sites, add or direct capacity more quickly, resolve outages instantly and provide businesses with on-demand connectivity.
The road to success
Many operators are anxious to start using open RAN, pushing the market forward. While they face technical and engineering challenges, many in the telco industry are confident that we will eventually figure out the logistics and details of a truly scalable commercial-grade open RAN solution.
The telco industry works with multi year planning cycles that can span decades. To get open RAN into those cycles, operators need to start taking action now, rather than waiting for all the answers before they commit to open RAN.
As each operator becomes more deeply involved in open RAN, whether through alliances and partnerships or in-house investigation and testing, the challenges will be met and the problems solved. The success of early open RAN deployments in specific industry use cases will encourage more operators, suppliers, and stakeholders to invest in open RAN and strengthen the movement towards this better-path infrastructure.
Conclusion
Open RAN is the evolution of radio access technologies from single-vendor proprietary systems to best-vendor open standards hardware and software. This change brings innovation and flexibility to networks, along with faster rollouts and easier upgrades and maintenance. But, open RAN is not an easy path to follow at this point in time, simply because it is so new.
Open RAN utilizes several technology trends, including 5G, cloud-native, distributed edge computing, and AI–driven automation. All of these can help push open RAN from being “just a cool new idea” to becoming a key contributor to flexible and cost-effective network infrastructure.
