B5GCASP: Decentralized Federated Anomalous Signaling Protection Architecture Using Functionally Layered Network

As the brain of B5G networks, the core networks enable more ubiquitous intelligent connectivity over previous generations of mobile networks, thanks to the decentralized user plane close to edges. As mitigation against abnormal signaling attacks on edge core networks, signal protection mechanisms for the user planes at the N4 interface are widely investigated. However, the prior art fails to adequately address the distribution characteristics of abnormal signaling at this interface, where single-point defences are insufficient for the complexities of beyond 5G (B5G) distributed architecture. This article proposes a decentralized federated anomaly signaling protection framework, called B5GCASP, based on a functionally layered anomalous signaling detection model (FLAD). Mainly, B5GCASP analyses abnormal signaling distribution under the packet forwarding control protocol (PFCP) at the N4 interface, distinguishing significant and nonsignificant anomalies. Coupled with a decentralized, federated detection mechanism, B5GCASP creates a comprehensive point-and-area detection architecture. Extensive experiments on the 5GC PFCP dataset show that B5GCASP achieves higher accuracy and faster detection of abnormal signaling compared to single-point defending baselines, which offer robust anomaly signaling protection for the B5G core network.