The Microcosm team will complete the simulation tool architecture early in Phase II, and in parallel begin to develop the simulation. The tool is architected for carrying out performance analysis and rapid trade study assessments of competing navigation/timing architecture options for future NASA missions, incorporating state-of-the art radiometric, x-ray pulsar, and laser communications measurements, among others, in the Orbit Determination Toolbox (ODTBX) environment. The solution centers on inclusion of a navigation layer as part of the communications architecture and on the maintenance and propagation of navigation states, time and associated uncertainties onboard each platform with filtering capabilities enabling updates based on any available measurements. Such measurements include: direct state and uncertainty updates via ground communication, radiometric- and lasercom-based range and range rate data from communication with ground stations and other spacecraft, time transfer from ground stations and other spacecraft, X-ray pulsar-based navigation and time measurements (XNAV), and others as they become available. This would be game-changing for spacecraft autonomy enabling platforms to operate using onboard state information rather than relying almost entirely on ground based tracking and activity scheduling. Additionally, architectures that include long-range intersatellite communication (e.g. relay spacecraft) can provide favorable geometries for significantly improved 3D precision navigation solar-system-wide.