Performance evaluations of advanced communication subsystems and their applications are necessary methods to prove that a certain level of communication functionality demanded and a required minimal processing power of end-systems (workstations) and of intermediate systems (networks and routers) have been achieved. The communication middleware package Da CaPo++ provides a modern communication platform that supports flexible communication services, in particular for end-systems. Based on an implementation of Da CaPo++ on workstations (Sun SPARCStations and Sun UltraSPARCs) a performance evaluation has been carried out. Specifically, the performance for relevant communication tasks is identified and overhead required for providing various degrees of communication service flexibility is illustrated. 1. General Information The research project KTI–Da CaPo++ is based on the project Da CaPo (Dynamic Configuration of Protocols) at the ETH. The extended system of Da CaPo++ provides a basis for an application framework for, e.g. , banking environments and tele-seminars. It includes the support of prototypical multimedia applications to be used on top of high-speed networks including dynamically configurable security and multicast aspects. This report is structured in one single part and contains the documentation on performance evaluations performed within Da CaPo++, which is based on the architectural and detailed design as described in TIK-Report No. 28 and the implementation documentation as described in TIK-Report No. 29.