Service Chaining Graph: Latency- and Energy-aware Mobile VR Deployment over MEC Infrastructures

Perceptual studies show that the Quality of Service (QoS) of large-scale Mobile Virtual Reality (MVR) applications is positively correlated to video frame rate and the duration of the immersive experience. These metrics depend on the sum of computation and network latency needed to generate and deliver a video frame to the Head-Mounted Display (HMD) and the power consumption on the HMD. Recent research shows that Multi-access Edge Computing (MEC) can support mobile HMDs to reduce their computing latency, but its potential to maintain the acceptable end-to-end (E2E) latency and reduce power consumption under high mobility conditions remains unexplored. This paper proposes Service Chaining Graph (SCG), an orchestrator to split VR applications into atomic services and deploy them across HMDs and MEC servers according to an optimization problem that aims to jointly minimize latency and energy consumption. Through simulations, we show that SCG reduces E2E latency by up to 74% in three high-mobility user-dense scenarios compared to four widely used service-migration strategies against a moderate increase in power consumption. Unlike other approaches, SCG can find a balance between average latency and energy consumption by migrating services between MEC servers and HMDs according to a policy depending on application requirements.