The open radio access network (O-RAN) is fast emerging as a promising alternative to the traditional RAN architecture given its potential in bringing down the network-related costs of telecom operators. By disaggregating the hardware and software elements of networks, O-RAN allows technology products from different vendors to coexist with various software platforms, thereby reducing operators’ dependency on a single vendor.
As the technology achieves further commercialisation, the ensuing flexibility to use solutions from multiple vendors is likely to spur competition amongst network equipment providers and reduce the total cost of deployment. The total cost of ownership of a traditional RAN accounts for 65-70 per cent of a mobile network’s total cost. According to industry estimates, operators can save up to 40-50 per cent on their capex and 30-40 per cent on opex by using O-RAN frameworks.
Further, under the traditional RAN, operators have followed a hardware-driven approach of deploying an additional layer to the network every time a new technology emerged. This required operators to invest substantially every few years to upgrade their networks. By obviating the need to replace the entire network gear to introduce new solutions, O-RAN can help operators lower their time-to-market and hence facilitate innovations in the industry.
Network equipment vendors also stand to gain from the proliferation of O-RAN since its deployment opens up market participation and lowers the barriers to entry. Further, because of interoperability, vendors can develop products for use by multiple operators instead of having to create customised solutions for a specific operator.
Given the potential benefits of O-RAN, telecom operators globally have announced their plans to switch from the traditional RAN to a more flexible network architecture. As of end September 2021, 73 operators from 38 telecom markets have either deployed or committed to O-RAN deployments, according to industry body GSMA.
Key enabler in 5G roll-out
Although O-RAN solutions hold the potential to reshape the mobile network ecosystem in general, they are increasingly becoming the technology of choice for operators, particularly for 5G network roll-outs. As 5G services will be used for a wide variety of use cases across multiple industries, the associated network topology and requirements such as throughput, latency and simultaneous connections will depend on each use case. To this end, O-RAN offers the advantage of combining components from a diversified supply chain to effectively accommodate multiple use cases.
Further, by enabling operators to increase the number of their network infrastructure partners, O-RAN is expected to help build better and more cost-effective 5G networks. Moreover, using O-RAN, telecom operators can create fully virtualised infrastructure capable of delivering critical 5G-based services. O-RAN can thus help operators reduce deployment costs, improve interoperability between vendors and bring intelligent computing to the edge of the network, thereby improving performance and unlocking new 5G capabilities.
As open interfaces enable the development of third-party artificial intelligence- and machine learning-driven solutions, O-RAN also holds the potential to enable telecom operators to leverage information from data traffic on their networks; this could be used to improve network performance. This is likely to be useful in the case of 5G and internet of things devices powered by 5G where a huge volume of data will be generated, opening up the possibility to derive several useful insights.
Indian operators jump on the bandwagon
Telecom operators in India are warming up to the idea of O-RAN as they look to reduce their network deployment costs and prepare for the launch of 5G services. Leading the pack is Reliance Jio Infocomm Limited (RJIL), which has announced its plans to roll out 5G services using its indigenously developed O-RAN architecture. The operator is currently testing voice and messaging applications using its 5G O-RAN solution in several cities and has partnered with chip manufacturers such as Qualcomm to make virtualised RAN and small cells to support its 5G network. RJIL also plans to export its indigenous 5G stack to other markets post the successful roll-out of the platform at a pan-India level. Meanwhile, Bharti Airtel has collaborated with vendors such as the Tata Group, Intel and Qualcomm to transform its existing fixed-function equipment-based communication network into a more flexible network framework. This switch to O-RAN, as per the company, will help it offer more innovative solutions to its customers in an increasingly hyperconnected environment.
Vodafone Idea has been leveraging the US-based software company Mavenir’s O-RAN solutions to scale up 4G adoption. Globally, the Vodafone Group is building one of the largest O-RAN networks in the world in collaboration with vendors such as Dell Technologies, NEC Samsung, Wind River, Capgemini Engineering and Keysight Technologies.
Stumbling blocks on the road to adoption
While O-RAN offers several cost and operational advantages over the traditional RAN, its adoption is likely to bring a new set of challenges for operators. Given the fact that with O-RAN telecom networks will comprise solutions from multiple vendors, it will become challenging for both operators and equipment manufacturers to ensure interoperability, manageability, optimisation and end-to-end performance of disparate components. Moreover, there is also a possibility of encountering incompatible configurations from multiple possible combinations of software and hardware. Besides increasing operators’ expenses on testing in a multivendor environment, troubleshooting is likely to become difficult as operators will require vendor-independent validation and troubleshooting to resolve network performance issues, which might not be the case in traditional single-vendor networks. To this end, the industry has taken several initiatives such as forming alliances of vendors and operators to test and validate interoperability in a controlled and managed environment.
The cost savings that accrue to operators upon using O-RAN are likely to hold true only for greenfield investments, as in the case of brownfield environments, where significant investments have already been made, replacing legacy networks with O-RAN will significantly raise the total network deployment cost. Many industry analysts also contend that the additional cost, time and effort to test and integrate multi-vendor systems could well offset, if not completely negate, any benefits accruing to operators from vendor diversity.
Moreover, ensuring compatibility with legacy networks in an O-RAN environment is a major challenge. Current O-RAN solutions are developed largely for 4G and 5G networks, while 2G and 3G standards remain the mainstay in many circles in India. Further, once 5G services are rolled out, deploying 5G RAN would require planning for a range of new features such as multiple-input, multiple-output antennas, large spectrum bandwidth and multiband carrier aggregation.
Network security is another major issue in an O-RAN environment. In a multivendor environment, each application exposes its programming interface to the services it provides and this opens up avenues for security breaches. Further, in an O-RAN network, some applications reside on cell sites, others on an operator’s private cloud and some outside of the operator’s private cloud. This is a departure from the prevailing security model in which the operator RAN is secured through a security perimeter. Hence, in an O-RAN environment, many security layers need to be established to ensure that the trust chain is maintained between applications and the underlying hardware. This would require standardised interfaces of different components of the heterogeneous network to test and validate the security layers.
Outlook
Although still in its infancy, O-RAN promises to offer several benefits over the existing RAN. By adopting open infrastructure, which comprises open source software, non-proprietary hardware and multivendor collaboration, operators can significantly reduce their network deployment as well as upgradation costs. O-RAN is also at the epicentre of the launch of 5G networks given its ability to support a plethora of 5G use cases.
O-RAN is gaining traction as 5G roll-out picks up pace and operators look to lower their capex and opex amidst rising capital intensity, and subdued subscriber and revenue growth. According to industry estimates, O-RAN revenues will constitute 10 per cent or more of the overall RAN market by 2025 from less than 1 per cent at present. However, integration complexity is likely to remain one of the major barriers in its adoption. The large-scale commercialisation of O-RAN is still many years away as operators, for now, are likely to rely on a single vendor instead of opting for multiple vendors for their end-to-end network needs. S
