This document is a technical report of the interdisciplinary research project Nexus which is a Center of Excellence that is carried out at the University of Stuttgart.

It is targeted at all interested readers who wish to delve deeper into the interfaces of the Nexus platform and the underlying architecture to get a better understanding of how the Nexus platform models the surrounding world and its manyfold context parameters.

This document is the successor of the Final Report of Design Workshop [Nicklas et al 2000], which at the time of its creation represented the specification for the implementation of the Nexus platform and went hand in hand with the formation of the research group Nexus. The successful research work accomplished in the following three years until 2003 uncovered even more open questions which resulted in the decision to found an interdisciplinary Center of Excellence. This document defines the specification of the Nexus platform’s interfaces, so that all participating projects have a common starting point and are able to build interoperable components. It does not contain real protocol definitions yet. Especially it does not cover error cases. These details can partially be found in the specifications of implemented components; however they should be included in a future version of this document.