Multi-carrier Measurement Study of Mobile Network Latency: The Tale of Hong Kong and Helsinki

Real time interactive cloud-based mobile applications such as augmented reality and cloud gaming require low and stable latency, especially in urban areas. These conditions are difficult to meet with the traditional single carrier LTE network access and consolidated server deployment in a cloud. Yet, with multiple SIM/multiple radio devices, latency can be kept under a given threshold through dynamic selection among multiple carriers and server deployment at network edge. To this end, it is necessary to understand how mobile network latency changes over time during a session with different carriers and how the server placement affects the latencies. In this paper, we present results from a measurement study of mobile network latency and jitter in 4G networks of Hong Kong and Helsinki, two very different cities in terms of population density and mobile infrastructure. Based on the results, we introduce a lightweight carrier selection algorithm that displays latencies 10 to 20% lower than single carrier operation.