Open RAN and SDN/NFV: Perspectives, Options, Restrictions and Challenges (No. 478) © Photo Credit: Robert Kneschke - stock.adobe.com

Open RAN and SDN/NFV: Perspectives, Options, Restrictions and Challenges (No. 478)

(full version only available in German)

Does everything stay different? Open RAN as new approach for radio access networks. The article discusses advantages and disadvantages of the Open RAN approach.

Summary

The fifth mobile communications generation (5G) is currently being rolled out by mobile network operators worldwide. In parallel, research work has begun on the sixth generation of mobile communications (6G). Both mobile communications generations are characterized by the fact that they include developments such as Software Designed Networks (SDN) and Network Function Virtualization (NFV), whereby the hardware in the respective mobile communications network is to concentrate on the core task of transmission and its control and the software for controlling the relevant processes is to be removed from the network nodes, generalized and (in the long term) transferred to generally available IT systems.

This development also includes an opening of interfaces in the radio access network (RAN), which is sometimes viewed controversially among market participants. Under the term "Open RAN", a new, disaggregated infrastructure in the RAN is being discussed and its respective components developed. Through software-driven processes, individual network functions can be controlled and managed at the central level of the RAN. With Open RAN, mobile network operators are pursuing the goal of being able to replace network elements more easily with hardware components from another manufacturer (multi-vendor environment). In this respect, the aim is to establish a new ecosystem in which, compared with the status quo, more manufacturers can supply different components of a network, including the necessary software. Mobile network operators expect this to increase the intensity of competition on the manufacturer side and intensify competition for innovation.

A major challenge of Open RAN is the comparatively complex integration of the desired multi-vendor environment. It is true that Open RAN can reduce existing Lock-in effects with regard to the procurement of network components from individual manufacturers. However, it is questionable whether new Lock-in effects will not arise once the integration of the new components in the radio access networks has been completed. Furthermore, the open interfaces envisaged between the individual network components represent a larger attack surface for cyber attacks, which is a further challenge. While at the political level Open RAN is also associated with greater digital sovereignty in Europe, the standardization is being driven quite significantly by companies from other continents. As a result, it remains to be seen whether Open RAN will actually be able to fulfill the promises associated with the concept. It is also becoming apparent that cloud infrastructure operators will play an increasingly important role in future radio access networks. In summary, there is still a need for further research in order to be able to assess the effects of Open RAN holistically.