In development of High Performance Computing and Networking (HPCN) for simulation applications several targets have to be realized. It is recpiired to maximize not only computational speed but also to maximize applicability in engineering environments. For applications in which HPCN-based simulations are economically and technically necessary tools, it is also essential to minimize the time-to-market of new HPCN tools. HPCN environments are characterized by the application of a variety of computer platforms: vector computers in single emd parallel processor modes, scalar computers with small or large numbers of processors, workstations and a variety of other processing servers for support functions. The computer platforms usually are integrated in a network. The complexity of the heterogenous HPCN computer networks and of the collections of software systems implemented on the networks increases continuously. With increasing economic relevance of HPCN also the need of co-operation of users of HPCN and of developers of HPCN facilities appears to increase. Management of the complexity and co-operation requires tools to realize the above-mentioned targets. In the present paper a software platform (SPINE) is described. The software platform can be installed on arbitrary networks of UNIX computers. The platform can be used for realization of HPCN environments for specific application areas such as computational fluid mechanics or computer aided software development. The platform offers for the specific application the required functions in an integrated way. This integration concerns user interaction, information management, control (concerning specific software as well as concerning the computer network) and processing. The software platform is illustrated with examples from three instantiations of the platform. These are for computational fluid dynamics, computer aided software engineering and computer aided control engineering for non-linear dynamic systems. SPINE appears to be very flexible.