In many cases, digital engineering is the only realistic answer to important trends in industry. This includes increasingly customized products, decentralized value chains, increasing complexity and functionality of products as well as the need to reduce the time to market. Digital Engineering has already resulted in many technology-driven changes of the product development process. Probably the most important change is the ability to execute some of the iteration loops of development and test completely in the virtual environment. Further improvements can only be achieved by simultaneously combining development and simulation tools from many different domains, such as mechanical engineering, physics simulation, and software engineering. This article identifies current research issues in the field of distributed interoperable testing environments. Moreover, two examples of current applications are given to illustrate what functionalities can already be utilized today.
