A Joint Handoff and Offloading Decision Algorithm for Mobile Edge Computing (MEC)

The main feature of Mobile Edge Computing (MEC) is to push computational resources and storage to the network edges (e.g., cellular base stations (BSs)) in order to offload computation-intensive and latency-sensitive applications from mobile devices. However, the deployment of MEC with a BS adds extra traffic to the already crowded cellular network that may lead to a radio congestion. On the other hand, user mobility triggers handoffs (HOs) not only between two BSs but also between two MECs, which creates new unique challenges of performing HOs to a target BS with an MEC which must have sufficient computational resources. Unfortunately, existing HO decision algorithms for traditional cellular networks cannot ad- dress these challenges. In addition, the radio network congestion issue is being utterly ignored. In this paper, we propose a novel HO decision algorithm for MEC systems that cooperates both radio and computation offloading. The proposed HO decision algorithm cooperates with femtocells to reduce the effect of radio congestion by offloading static traffic. It also cooperates with the remote cloud to reduce the impact of congestion at the MEC by offloading delay- tolerant computation. Simulation results show that our proposed HO decision algorithm significantly improves the offloading success and the service failure rates. To the best of our knowledge, this is the first HO decision algorithm that addresses both radio and computation offloading issues and mobility together in MEC systems.