xApp-Level Conflict Mitigation in O-RAN, a Mobility Driven Energy Saving Case
Abdul Wadud, Fatemeh Golpayegani, Nima Afraz
TL;DR
This work tackles xApp-level conflicts in Open RAN by formulating a theoretical framework based on conflict graphs to characterize direct, indirect, and implicit conflicts and their KPI impacts. It introduces a rule-based, low-latency conflict detection mechanism with a QoS-aware mitigation approach (QACM) that leverages NSWF and EG solutions within a CMS comprising CDC/CMC. The methods are evaluated in a mobility-driven Mobility Robustness Optimization (MRO) and Energy Saving (ES) scenario via MATLAB simulations, showing QACM delivers the best energy efficiency and reduces link failures and unnecessary handovers, with rapid detection latency (~0.4–0.5 ms). The results support scalable, QoS-conscious conflict management for Open RAN, with future work focusing on larger-scale deployments, multi-objective optimization, and ML-based mitigation techniques. This work advances practical Open RAN deployments by providing formal conflict definitions, graph-based representations, and a concrete QoS-aware mitigation pathway.
Abstract
This paper investigates the emerging challenges of conflict detection and mitigation in Open Radio Access Network (O-RAN). Conflicts between xApps can arise that affect network performance and stability due to the disaggregated nature of O-RAN. This work provides a detailed theoretical framework of Extended Application (xApp)-level conflicts, i.e., direct, indirect, and implicit conflicts. Leveraging conflict graphs, we further highlight how conflicts impact Key Performance Indicators (KPIs) and explore strategies for conflict detection using Service Level Agreements (SLAs) and Quality of Service (QoS) thresholds. We evaluate the effectiveness of several mitigation strategies in a simulated environment with Mobility Robustness Optimization (MRO) and Energy Saving (ES) xApps and present experimental results showing comparisons among these strategies. The findings of this research provide significant insights for enhancing O-RAN deployments with flexible and efficient conflict management.
