The aim of this project is to propose suitable queueing models and to develop associated mathematical analysis techniques for the performance analysis of queueing systems with multiple types of customers. Such models are necessary for a good understanding of queueing phenomena within application domains such as digital communications, cluster computing, traffic networks, ..., where the customers to be served (information packets, jobs, vehicles, ...) are typically heterogeneous in terms of arrival characteristics, required service times, required service capacity (necessary number of available servers) and/or expected service quality.