The implementation of the smart grid and the related use cases requires the interaction of a wide variety of systems from many manufacturers. The selection of suitable communication protocols is a key factor in achieving the necessary interoperability and avoiding vendor lock-ins. Considering the large number of possible protocols, this selection process is becoming increasingly difficult and time-consuming. To simplify and accelerate this process, the use of a morphological box is presented. The partial aspects defined in the morphological box are chosen in such a way that they can describe both the requirements of a use case and the possibilities of the protocol under assessment. Applying the box eventually results in reusable profiles that allow the comparison of use cases and protocols in a quick and simple way. The utilization is demonstrated by evaluating the MQTT protocol for the realization of a given use case.