Security, Privacy, and Trust for Open Radio Access Networks in 6G

The programmability of radio access networks was already introduced in the fifth generation of mobile networks by leading the pathway towards the Open RAN. To cater the stringent requirements emerging with the novel services and use cases, Open RAN is becoming integral to 6G as well. The most highlighted characteristics of Open RAN such as disaggregated architecture, cloudification of network functions, open interfaces, and intelligent network management are also associated with many challenges related to the security of the end-to-end telco networks. Most existing research works and specifications focus on security in Open RAN in 5G. In this paper, we discuss the role of Open RAN in 6G focusing on three aspects such as security, privacy, and trust, while highlighting their emerging trends and relevance to 6G. Our contributions include presenting a holistic view of Open RAN security within the 6G ecosystem, with insights into use case and stakeholder perspectives and standardization efforts. This includes a concise update on Open RAN security in the 5G era and their applicability to 6G exploration. Moreover, we identify the key research endeavors focused on privacy and trust in Open RAN, with an emphasis on their development toward 6G. Finally, we discuss the possibilities of incorporating energy awareness, quantum-safe solutions, and other emerging technological enablers with Open RAN security.