Security of East-West Interface of SDN: A Review of Challenges, Solutions, and Future Directions
Hamad Alrashede, Fathy Elbouraey Eassa, Abdullah Marish · Engineering Technology & Applied Science Research · 2025
The east-west interface in Software Defined Networking (SDN) plays a crucial role in enabling inter-controller communication, which is vital for scalability, load balancing, and fault tolerance in distributed SDN environments. Despite its importance, this interface remains vulnerable to serious security threats, such as Man-in-the-Middle (MitM), unauthorized access, False Data Injection (FDI), and Distributed Denial-of-Service (DDoS) attacks. Unlike previous studies and reviews that focus broadly on SDN security, this paper presents a comprehensive review of the current security challenges and proposed solutions that are specific to the east-west interface. The literature is organized into five categories: cryptographic techniques, authentication and access control, blockchain-based mechanisms, Machine Learning (ML) approaches, and hybrid models. In addition, an analytical contribution is provided by introducing a threat-solution coverage matrix that maps each reviewed solution to the specific types of attacks it mitigates. This analysis highlights under-addressed vulnerabilities and uncovers critical research gaps. Future research directions are provided, including the adoption of zero-trust architectures and the need for standardized benchmarking protocols.