We shall develop and commercialize TimeWiz» a friendly, sophisticated and integrated modeling, analysis and visualization software package which has: 1) a highly visual and interactive interface, 2) a sophisticated diagramming utility with software and hardware components and connectors, 3) a hierarchical representation scheme for unlimited levels of hardware/software abstractions, 4) a catalog facility for visual and behavioral customization, 5) a facility to bind software to hardware components automatically and/or manually, 6) extensive timing analysis capabilities using Rate-Monotonic Analysis, 7) a charting facility, 8) a reporting facility for a complete system summary, and 9) a property inspector to display properties of the selected component. A working prototype of TimeWiz was successfully built and demonstrated during our Phase I effort. We now propose to: a) add significant new analytical capabilities including end-to-end timing analysis, hardware reliability analysis, system overhead inclusion, COTS operating system support, hierarchical binding, and custom catalog of components, b) extend, complete and integrate the state-of-the-art user-interface of TimeWiz including custom report generation, custom plotting, comprehensive drag-and drop support, cut-and-paste, undo/redo, a customizable environment, and, c) validate all TimeWiz features on a host of complete case-studies. We also propose 1) a powerful simulation facility to capture all behaviors of distributed systems, 2) end-user extensibility for custom analytical techniques and, 3) an active monitoring and control facility for debugging and tuning multiple live embedded targets.