Dynamic Service Entity Placement for Latency Sensitive Applications in Transportation Systems

With the development of applications on end devices, such as cell phones and tablets, more and more passengers would like to have entertainment on these end devices when they are cruising on vehicles. Due to the limited computation ability of the end devices, some of these applications have back-end components on the edge clouds, which are realized by Service Entities (SEs). In this work, we propose a system named DSEP to Dynamically determine the SEPlacement, such that the maximum latency experienced by the passengers can be minimized. To this end, we first train two sequential neural networks to predict the position of each individual vehicle, and propose an efficient algorithm based on optimization relaxation and Lagrange decomposition to determine the SE placement. Through extensive real-data driven simulations, we find that with the two sequential neural networks proposed in this paper, there are less than 1 percent errors on estimating where the passengers will access the edge cloud system. When the computation resources in the edge cloud are limited, DSEP can reduce the response latency by up to 43 percent compared with the nearest placement scheme. Even averaging the performance improvement over all simulation settings, DSEP can reduce the response latency by 16 percent.