Message Class Process Class Packet Class Packet A Class Packet B Class Packet C Class Light Weight Process Class Oper System Process Class System Class Processor Class Disk Class TCP / IP Class

An object-oriented modeling infrastructure using the Javabased, Silk simulation classes is defined that enables the simulation of multitasking, distributed systems using symmetric multiprocessors. The simulation infrastructure is being used to evaluate alternative architectures for embedded, distributed systems. We show how the underlying structure is adapted to several different applications, including various Internet applications. The paper describes the infrastructure, its robustness, and the application of the model to produce insights for a system under design. The simulation infrastructure enables a high fidelity representation of the internal complexity of the application on each processing node, the operating system behavior, and the disks and network. The simple yet powerful representation leverages the use of the Silk entity-thread architecture to achieve a simulation architecture that maps to the actual system architecture in both conceptual design and processing sequence. The model has been validated through instrumentation of the evolving target system.