In this thesis we examine the feasibility of providing interconnections of Local Area Networks (LANs) in various remote plants of the same company in a mesh topology to form a Private Business Network (PBN) over a broadband satellite communications system. Such a PBN consists of several User Terminals (UTs); each connected to the router of a LAN in a given plant. A satellite system supports a number of PBNs by dynamically sharing the satellite resources. We considered Internet Protocol (IP) based LANs using IPv6 and Resource Reservation Protocol (RSVP) to support both real-time and non-real time traffic. We propose a Medium Access Control (MAC) protocol for broadband satellite Inter-LAN services with a special emphasis on the convergence sublayer. In order to efficiently utilize the satellite resources in serving bursty multimedia traffic, the Combined Free- and Demand-Assignment Multiple Access (CFDAMA) techniques are used in conjunction with Multiple-Frequency Time-Division Multiple-Access (MF-TDMA) format for Dynamic Capacity Allocation (DCA). Functions of the UT and Master Control Station (MCS) are described. We describe the translation of Quality of Service (QoS) requirements to service categories and the handling of aggregated requests. We provide a formal model of the MAC layer using the Specification and Description Language (SDL). Moreover, the proposed SDL model is simulated and validated using the ObjectGEODE tool.