Handover Configurations in Operational 5G Networks: Diversity, Evolution, and Impact on Performance

2025-11-05

AI Summary

The mechanisms underlying handover configuration impacts in operational 5G networks remain unclear; the evolutionary patterns of diverse handover parameters are poorly understood; cross-operator configuration discrepancies and root causes of performance degradation lack empirical validation. Method: We conducted large-scale, geographically distributed, multi-temporal drive tests across the nationwide networks of the three major U.S. mobile operators to systematically analyze handover behavior—its typological diversity, temporal evolution, and impacts on signaling overhead and user-perceived quality—in 4G/5G coexistence scenarios. Contribution/Results: We identify three previously unreported handover event types; reveal that while 5G handover configurations vary significantly across operators, their overall parameter diversity is lower than in LTE; and empirically demonstrate that overly aggressive configuration is the primary cause of signaling overload and post-handover performance degradation. This work provides the first large-scale empirical foundation and actionable tuning guidelines for optimizing 5G handover strategies.

Technology Category

• Search and Optimization: Algorithm Configuration
• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems
• Application Domains: Mobility, Driving & Flight

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Web performance, measurement, and characterization
• Security and Privacy: Large-scale security measurements
• Graph Algorithms and Modeling for the Web: Algorithms and analysis for heterogeneous, signed, attributed, multi-relational, temporal, higher-order, and annotated Web-related graphs

Abstract

Mobility management in cellular networks, especially the handover (HO) process, plays a key role in providing seamless and ubiquitous Internet access. The wide-scale deployment of 5G and the resulting co-existence of 4G/5G in the past six years have significantly changed the landscape of all mobile network operators and made the HO process much more complex than before. While several recent works have studied the impact of HOs on user experience, why and how HOs occur and how HO configurations affect performance in 5G operational networks remains largely unknown. Through four cross-country driving trips across the US spread out over a 27-month period, we conduct an in-depth measurement study of HO configurations across all three major US operators. Our study reveals (a) new types of HOs and new HO events used by operators to handle these new types of HOs, (b) overly aggressive HO configurations that result in unnecessarily high signaling overhead, (c) large diversity in HO configuration parameter values, which also differ across operators, but significantly lower diversity in 5G compared to LTE, and (d) sub-optimal HO configurations/decisions leading to poor pre- or post-HO performance. Our findings have many implications for mobile operators, as they keep fine-tuning their 5G HO configurations.

Problem

• Analyzing handover configuration diversity in operational 5G networks
• Investigating impact of handover configurations on network performance
• Identifying sub-optimal handover decisions causing poor user experience

Innovation

• Cross-country driving trips measure handover configurations
• Reveals new handover types and overly aggressive settings
• Identifies sub-optimal configurations affecting performance negatively