The increasing needs for Internet services on the wire communication networks and the terrestrial radio networks in the world recently are caused the shortage of these resources and required to develop the alternative resources such as satellites. ETRI has been developing BSAN(Broadband Satellite Access Network) system for the interactive multimedia services to use as a platform to provide the high speed Internet service since 2000. The services provided by BSAN system are the high-speed internet access, multicast & broadcast services based on IP and MPEG-2 A/V services on the basis of DVB-S and RCS specifications. The IP packets encapsulated into MPEG2-TS packets through SIS(Satellite Interface Subsystem) on the forward link have transmitted to RCSTs(Retum Channel Satellite Terminal) with the data rate of 2 to 45 Mbps and IP packets over ATM on the return link have transmitted to the SIS with the data rate of l28ksps to 2.O48Msps. BSAN system has consisted of the SIS and the several hundreds RCSTs and each RCST is operated alone or with several tens of user PCs. RCST as a group terminal would provide high speed IP services to several tens of user PCs via LAN. This paper describes the system architecture including the configuration of SIS and RCST, forward link and return link technologies and the connection control and the synchronization procedures.