In the 5G era, the open radio access network (Open RAN) is gaining traction as it has the potential to accelerate 5G adoption and make it more cost-effective, particularly for smaller mobile network operators. A key advantage of Open RAN is that it provides telecom operators freedom from proprietary hardware and software offered by a single vendor, which has been the norm in the telecom industry.

A recent report by GSMA highlights that Open RAN has the potential to reduce the cost of deploying mobile networks by up to 30 per cent. Further, it promotes greater competition among vendors, paving the way for lower prices, increased innovation and ultimately, better services for consumers. These advantages build a strong case for Open RAN adoption across the telecom do­ma­in, creating exciting new opportunities for stakeholders across the value chain.

Key components of Open RAN

The primary components of Open RAN are:

  • Cloudification: Open RAN architecture involves hardware and software disaggregation and utilisation of RAN ap­plications as cloud-native functions. The three primary building blocks of 5G RAN are the radio unit, the distributed unit and the centralised unit.
  • Intelligence and automation: Open RAN technology uses open manageme­nt and orchestration with external arti­ficial intelligence (AI)/machine learning (ML) capabilities. In addition, it has RAN automation interfaces.
  • Open internal RAN interfaces: 5G Open RAN technology includes interfa­ces defined by the 3rd Generation Par­t­nership Project (3GPP) and the Open RAN Alliance. These interfaces are higher lay­er split, inter-node communication, O-RAN lower layer split and near-real-time RAN intelligent controllers (RICs).

Open RAN network architecture and transition strategies

In terms of network architecture, Open RAN utilises a cloud computing platform comprising physical infrastructure nodes with open architecture. It also creates and hosts various virtual network functions used by RICs and other infrastructure elements. Cloud RAN is a virtualised RAN designed to be cloud-native. It is built with future-proof architecture, and incorporates key elements such as micro­services and containerisation. A secure, modern cloud-na­ti­ve implementation of Open RAN relies on securing the underlying microservices-based architecture.

Telecom operators need to undergo significant network transformation to de­ploy Open RAN. This involves making the network more software-driven and pro­­moting interoperability among multi-vendor equipment across different generations of networks. By adopting open architecture, telecom companies can introduce more efficient equipment from different vendors, thereby reducing costs. Further, Open RAN facilitates standardisation of the network infrastructure, making it che­aper and easier for telecom companies to implement network changes.

Apart from interoperability and disaggregation of hardware and software, ORAN incorporates selfhealing and self-configuration properties across the network. It also promotes cloud-native deployments, enabling easy and affordable maintenance and upgrades, resulting in a potential cost reduction of up to 30 per cent.

Apart from interoperability and disaggregation of hardware and software, Open RAN incorporates self-healing and self-co­nfiguration properties across the netwo­rk. It also promotes cloud-native dep­loy­ments, enabling easy and affordable maintenance and upgrades, resulting in a potential cost reduction of up to 30 per cent.

This means that telcos no longer need to add a new layer for a new technology. They can upgrade the network simply by executing a software upgrade, eliminating the need for site visits and making it easier for service providers to introduce new products and services for their subscribers. Mo­re­over, the adoption of a common op­en standard enables telecom operators to save on infrastructure costs by streamlining their deployments, and providing better coverage at a much lower energy consumption rate.

Developments in India

The Open RAN environment in India is developing gradually. In May 2022, the Telecommunication Enginee­ring Centre, a technical arm of the De­part­ment of Tele­communications (DoT), signed a five-year MoU with an Indian product engineering and manufacturing company to allow registered start-ups, innovators, and micro, small and medium enterprises (MSMEs) working in the Open RAN space to test their products at the company’s labs to en­su­re interoperability among Open RAN components from various vendors. Further, the Centre for Development of Telematics (C-DOT) signed an agreement with VVDN Techno­logies and the IIT Hyde­rabad-incubated start-up WiSig Networks to develop 5G Open RAN products and other equipment.

Indian telecom players are also looking to scale up their Open RAN deployments. All the three major telcos are exploring the Open RAN domain. To this end, in April 2022, Bharti Airtel conducted India’s first Open RAN-based live 5G network vali­dati­on in partnership with Mavenir. Airtel was also the first operator in India to commercially deploy an open virtual RAN (vRAN) solution based on disaggregated and open architecture defined by the O-RAN Alli­a­nce. Reliance Jio is also building a 5G network solution based on Open RAN. It has tested the solution in several cities. Fur­ther, Vo­­­dafone Idea Limited (Vi) has deployed Ma­­venir’s Open RAN solutions for 4G services.

By adopting open architecture, telecom companies can introduce more efficient equipment from different vendors, thereby reducing costs. Open RAN facilitates standardisation of the network infrastructure, making it cheaper and easier for telecom companies to implement network changes.

To promote innovation and increase adoption in the Open RAN space, in May 2023, the Indian government launched an Open RAN test bed for conformance, certification and interoperability testing of Open RAN-based solutions. The test bed, developed by C-DOT, aims to help innovators, start ups, MSMEs and other stakeholders to test Open RAN technology. As per the government, this initiative will faci­litate research and development in the area of Open RAN by ex­tending testing facilities for the expansion of the Open RAN ecosystem in India. It will facilitate the testing of Open RAN elements and the development of a fully indigenous 5G radio network in India. It will also facilitate the certification and bad­ging of subsystems that conform to the 3GPP and Open RAN Alli­ance specifications.

Advantages of Open RAN in rural areas

Open RAN technology can prove to be an asset in enhancing rural connectivity. This is because cloud-based RIC, which is res­ponsible for managing 5G network functions such as network slicing and prioritised communications, is a crucial component in Open RAN architecture. The RIC is virtualis­ed, inherently scalable, and presents signi­ficant opportunities for operators to de­ve­lop new applications to optimise their networks, build new services, as well as control multiple vendors in the rural Open RAN space. The challenging radio environment of a dense urban deployment adds considerable complexity to network management, making the more distributed rural Open RAN en­vironment a much better test bed for de­veloping, testing and piloting new services.

Another key factor is maintenance overhead, which is traditionally a considerable challenge in the rural network environment. The use of virtualisation and built-in ability to remotely update the network edge makes even more sense in a geographically dispersed deployment such as rural areas.

Operators in India have already started exploring this possibility. Airtel has re­por­tedly selected Mavenir to deploy Open RAN technology in the low-revenue-generating rural parts of India in order to lower its capital expenditure. The telco pla­ns to initially deploy 2,500 sites on Open RAN and scale up to 10,000 sites over time. The disaggregation of the radio using open technologies is expected to im­prove the total cost of ownership.

Opportunities and outlook

Net, net, there has been a rapid shift to­wards Open RAN over the past few years. The deployment of this technology is only going to increase in the future. Acc­ording to a recent report by the Dell’Oro Group, Open RAN already comprises a mid-single-digit share of the broader RAN market. The firm predicts that Open RAN revenues are set to account for more than 15 per cent of the global RAN market by 2027. This implies that the global telecom market has barely scratched the surface of the rapidly expanding network domain.