MoDEMS: Optimizing Edge Computing Migrations for User Mobility

Edge computing systems benefit from knowledge of short-term mobility from 5G technologies, as tasks offloaded from user devices can be placed at the edge to reduce their latencies. However, as devices move, they will need to offload their tasks to different edge servers, which may require migrating data from one edge server to another. In this paper, we introduce MoDEMS, a system architecture through which we provide a rigorous theoretical framework to study the challenges of such migrations to minimize the service provider cost and user latency. We show that this cost minimization problem can be expressed as an integer linear programming problem, which is challenging to solve due to resource constraints at the servers and unknown user mobility patterns. We show that finding the optimal migration plan is in general NP-hard, and we propose alternative heuristic solution algorithms. We finally validate our results with realistic user mobility traces