Optimization of ad hoc device and service discovery in large scale networks

Device and service discovery is an essential part of automation networks in order to ensure the interoperability of devices and Plug&Play functionalities. Embedded Web services such as Devices Profile for Web Services are an upcoming technology for building and factory automation. For ad hoc discovery, the WS-Discovery standard is used. This approach avoids single points of failures. However, it shows low scalability due to static response time values. The rising number of devices leads to an increasing network load and especially to an increasing device processing load as a result of the discovery process. In this work, we evaluate the issues of ad hoc service discovery and suggest an optimized algorithm for dynamic data rate reduction in large scale networks. Moreover, the suggested improvements allow reducing peak data rates by more than 50% for constant timing parameters. Using the suggested approach, the ad hoc discovery can be applied in any network size. The desired peak data rates or response times of the system can be significantly reduced and dynamically adjusted according to the desired values. This approach guarantees a scalable ad hoc discovery mechanism and is backward compatible with legacy equipment.