From Cell Towers to Smart Street Lamps: Placing Cloudlets on Existing Urban Infrastructures

Cloudlets are small-scale offloading units for low-latency demands, offering a unique opportunity for emerging smart city applications such as autonomous driving or augmented reality. While previous works have investigated the general concept of cloudlets, little attention has been directed to the question of where to actually place cloudlets on existing infrastructure in a city. Due to cloudlets' heterogeneity in this context, their placement remains challenging. In this paper, we first provide a thorough analysis of a city-wide cloudlet infrastructure deployed on three types of existing infrastructures that act as wireless access points: cellular base stations, commercial off-the-shelf routers, and smart lamp posts. Based on real-world data for the access point locations in a major city and movement traces of two mobile applications, we analyze multiple coverage metrics to gain insights on the practicability of leveraging these infrastructures for a city-scale deployment of cloudlets. As a second major contribution, we propose a novel placement strategy that takes into account the heterogeneity in terms of communication ranges, resources, and costs associated with each type of cloudlet. Our strategy enables the tradeoff between deployment cost and quality of service as required for different deployment scenarios. The effectiveness of our strategy is confirmed through real-world-trace-based evaluation.