End-to-End V2X Latency Modeling and Analysis in 5G Networks

5G networks provide higher flexibility and improved performance compared to previous cellular technologies. This has raised expectations on the possibility to support advanced V2X services using the cellular network via Vehicle-to-Network (V2N) and V2N2V connections. Replacing direct V2V connections by V2N/V2N2V communications to support critical V2X services requires low V2N/V2N2V latencies. It is then necessary to quantify the latency values that V2N and V2N2V connections can achieve over 5G end-to-end (E2E) connections, but these depend on the particular 5G network deployments and configurations and to date the number of related studies is limited. This paper progresses the state-of-the-art by introducing a novel E2E latency model to quantify the latency of 5G V2N/V2N2V communications. The model includes the latency introduced at the radio, transport, core, Internet, peering points and application server (AS) for single MNO and multi-MNO scenarios. This paper estimates the E2E latency for a large variety of possible 5G network deployments that are being discussed or envisioned to support V2X services. This includes the possibility to deploy the V2X AS from the edge of the network to the cloud. The model is utilized to analyze the impact of different 5G network deployments and configurations on the E2E latency. The analysis helps identify which 5G network deployments and configurations are more suitable to meet V2X latency requirements. The conducted analysis highlights the challenge for centralized network deployments that locate the V2X AS at the cloud to meet the latency requirements of advanced V2X services. Locating the V2X AS closer to the cell edge reduces the latency. However, it requires a higher number of ASs and also a careful dimensioning of the network and its configuration to ensure sufficient network and AS resources are dedicated to serve the V2X traffic.