Ongoing research is described that is focused up on modelling the space base information network and simulating its behaviours: s imulation of spaced based communications and networking project. Its objective i s to demonstrate the feasibility of producing a tool that can provide a performa nce evaluation of various constellation access techniques and routing policies. The architecture and design of the simulation system are explored. The algorithm of data routing and instrument scheduling in this project is described. Besides these, the key methodologies of simulating the inter-satellite link features i n the data transmissions are also discussed. The performance of both instrument scheduling algorithm and routing schemes is evaluated and analyzed through exten sive simulations under a typical scenario.
