Waiting Time Estimation for Periodic Traffic Sources in a Chain of Nodes

Commercial-off-the-shelf (COTS) components are used in numerous communication systems and application fields for cost reduction. While this trend is adopted in various home and business scenarios, most components for safety critical systems are proprietary or significantly modified. This also applies to networks using IP over Ethernet. Hardly any accepted methods to certify safety critical communication networks with such COTS components exist.,, This paper presents a Queueing Theory based heuristic to estimate end-to-end delay times for IP and Ethernet based communication systems with periodic traffic sources. Traffic source models depending on few parameters, e.g. Interrupted- Poisson-Processes (IPPs), are used. Required input is information on the sources, network topology and routing, which can be easily obtained in some domains, e.g. for maritime vessels. The methods are therefore demonstrated for a ship network.