Building a Security Canopy Over O-RAN: The SDP Paradigm

The Open Radio Access Network (O-RAN) architecture provides flexibility in the deployment of RAN but introduces significant security vulnerabilities due to its open interfaces and disaggregated nature, expanding the attack surface for threats such as DoS, DDoS, MiTM, and unauthorized access. Current security solutions lack comprehensive protection across O-RAN components and interfaces.

This paper proposes an O-RAN-SDP framework integrating Software Defined Perimeter (SDP) principles to establish Zero-Trust security in O-RAN. By deploying an SDP Controller (SDPC) as an xApp within the Near-RT RIC and embedding SDP agents in O-RAN components, the framework leverages Single Packet Authorization (SPA) and secure tunneling mechanisms. The proposed architecture ensures strong authentication, granular authorization, reduced attack surface, and protection against DoS/DDoS, MiTM, and zero-day vulnerabilities across the O-RAN ecosystem. Experimental evaluation on a real O-RAN testbed demonstrates effective attack mitigation with acceptable connection setup overhead.