Open RAN: A Concise Overview

Open RAN has emerged as a transformative approach in the evolution of cellular networks, addressing challenges posed by modern applications and high network density. By leveraging disaggregated, virtualized, and software-based elements interconnected through open standardized interfaces, Open RAN introduces agility, cost-effectiveness, and enhanced competition in the Radio Access Network (RAN) domain. The Open RAN paradigm, driven by the O-RAN Alliance specifications, is set to transform the telecom ecosystem. Despite extensive technical literature, there is a lack of succinct summaries for industry professionals, researchers, and policymakers. This paper addresses this gap by providing a concise, yet comprehensive overview of Open RAN. Compared to previous work, our approach introduces Open RAN by gradually splitting up different components known from previous RAN architectures. We believe that this approach leads to a better understanding for people already familiar with the general concept of mobile communication networks. Building upon this general understanding of Open RAN, we introduce key architectural principles, interfaces, components and use-cases. Moreover, this work investigates potential security implications associated with adopting Open RAN architecture, emphasizing the necessity of robust network protection measures.