The central idea behind interface-based design is to describe components by a component interface. In contrast to a component description that describes what a component does, a component interface describes how a component can be used. A well designed component interface provides enough information to decide whether two or more components can work together properly in a system. In this work, we expand the idea of interface-based design to the area of real-time system design. Here, the term of ’working together properly’ refers to questions like: Does the composed system satisfy all requested real-time properties such as delay and throughput constraints? For this, we introduce Real-Time Interfaces, that connect the principles of Real-Time Calculus with Interface-based Design. In contrast to traditional real-time system design, in interface-based real-time system design the compliance to real-time constraints is checked at composition time. This leads to faster design processes and...