Since emerging networked applications require a variety of different communication services, the number of communication subsystems and approaches to deliver flexible services has increased. Nevertheless, applications have to be programmed sufficiently on top of these communication subsystems. Providing an easy-to-use and intuitively programmable communication service for multimedia applications, an up-to- date application programming interface is needed. The developed approach offers an object-oriented interface for setting-up, accessing, and managing communication services. Moreover, these services may be of flexible nature, offering the potential to application programmers to specify communication requirements in a set of application-dependent quality-of-service (QoS) parameters. Service needs and communication demands are specified by, e.g., bandwidth requirements, delay bounds, or authentication requests. The developed and implemented application programing interface hides away communication-relevant information from applications and provides a set of efficient and stream-lined interface functions and operations.