- Executive Summary
The history of cellular network development is a journey of standardization and increasing openness. The opening of the standard interface between RAN and Core Network (CN) improved market competition and promoted industry development. More recently as 4G/LTE economics drove more flexible configurations - Centralized RAN, Cloud RAN (C-RAN and now Virtualized RAN (vRAN) it became clear that there were insufficient open intra-RAN interfaces. Operators’ choice of vendors was limited by their incumbent radio access network infrastructure. In 2019 5G NR brings new challenges of higher cost and greater complexity. Telecom operators need to encourage new entrants into the market – to stimulate innovation and lower the network costs. A truly Open RAN ecosystem could increase competition. Therefore leading tier-1 operators have formed the O-RAN Alliance to build a more open and smarter RAN architecture.
In parallel, leading Internet companies, such as Facebook and Google are also keen to have a low cost wireless network infrastructure that will provide affordable broadband connectivity to people everywhere in the world. Facebook-started the Telecom Infrastructure Project initiated an OpenRAN Project that has similar goals to those of the O-RAN Alliance, i.e. to lower RAN costs and to improve RAN flexibility. Vodafone and Telefonica are active members of the group. O-RAN Alliance and OpenRAN Project Group share the similar approach specifically:
- Decoupling of hardware and software
- Decoupling of control plane and data plane
- Based on Commercial-Off-The-Shelf (COTS) hardware and open source software
- Virtualization of physical resources
- Standard interfaces with true multi-vendor interoperability
Vodafone and Telefonica have already launched an OpenRAN RFI and are running OpenRAN trials in Asia, Africa and Latin America this year. China Mobile has also built a white box small cell reference design and kicked off trials in the framework of O-RAN Alliance. China Mobile expects the white box small cell will be commercially available in 2020 – 2021.
These trials indicate the progress of the Open RAN campaign but also demonstrate the limitations of today’s Open RAN activities. Most of Open RAN projects focus on software, COTS hardware and digital processing, but lack of a high power RF solution for base station implementation has been a high barrier for new entrants. In many cases, other components of cell site infrastructure are the most significant contributors to the cost of RAN and network deployment. To address these costs, the Open RAN vision needs to extend to cover not only the RF solution but the complete cell site infrastructure as well.
Incumbent vendors will face serious challenges as an Open RAN ecosystem emerges. Their R&D strategy, business models, organizations and even corporate culture may have to change. On the other hand, incumbent vendors should be able to leverage their superior expertise and the trust telecom operators have in them to play a leading role in this changing world.