Explainable AI to Understand the Latency Behavior of Public Cloud Service Platforms

Abstract

Cloud platforms have become a core component of the Internet because most services and products rely on them to host their backends. Estimating and understanding the latency experienced when accessing those cloud platforms is a challenge of growing importance that has not been sufficiently studied. To address this relevant matter, we conducted a three-month measurement campaign, collecting traceroute data every 30 min across 256 source–destination probe pairs. Our specific goal is to analyze whether the current network is able to provide adequate performance for emerging applications and services. We use this dataset to evaluate the performance of forecasting algorithms when predicting cloud latency from both temporal and spatial perspectives, and we leverage post-hoc explainability methods to identify the drivers affecting latency. Several prior studies provide public cloud-latency datasets, but these datasets are generally analyzed in isolation. To close this gap and provide a cross-dataset comparative analysis of cloud-latency measurements, we analyzed the related publicly available datasets and applied a common forecasting and explainability workflow to compare their findings. Our analysis reveals that operators do not require complex methods to predict latency and that distance and a few other simple features are sufficient to achieve operationally accurate predictions. We find latency to be remarkably stable from the user’s perspective, both over the duration of the campaign and across hours of the day, which contrasts with previous findings, and we show that the specific path traversed has a significant impact on latency.