Mobility-Aware Service Migration in Fog: A Comprehensive Literature Review

Abstract

Mobility-induced service migration has become pivotal in fog computing to maintain low latency and service continuity for moving users and devices. This literature review provides an in-depth analysis of primarily peer-reviewed journal research on mobility-aware service placement and migration techniques in fog environments. We first discuss the scope and motivation, highlighting the challenges that frequent mobility poses to edge-hosted applications. We present a thematic synthesis that categorizes the state-of-the-art into optimization-based frameworks (e.g., cost/reward-driven and heuristic algorithms), machine learning and reinforcement learning approaches, proactive vs. reactive handoff strategies, and system-level solutions (architectures, platforms, simulators) enabling live migration. Two comparison tables summarize the key approaches and the platforms/tools for mobility support. A critical analysis is provided, contrasting techniques in terms of decision models, overheads, QoS outcomes, and applicability across scenarios like smart cities, vehicular networks, and industry 4.0. We identify contradictions and trade-offs – for example, between minimizing latency and limiting migration frequency or energy use – reported across studies. Furthermore, research gaps are delineated, including the need for more accurate mobility prediction, energy-efficient yet low-latency migrations, and improved security in multi-stakeholder (federated) fog environments. Finally, future directions are suggested, pointing toward holistic mobility management frameworks, including emerging AI-enabled approaches for adaptive migration, and real-world testbed validations to bridge the gap between simulation and deployment. This review aims to guide researchers in developing robust fog systems that gracefully handle user mobility while meeting stringent Quality of Service requirements.