Improving the efficiency of circuit-switched satellite networks by means of dynamic bandwidth allocation capabilities

Current satellite systems operate according to circuit switching transfer modes. To improve flexibility and efficiency, several kinds of packet switching systems have been proposed. However, it appears that full packet switches are still too complex and expensive to be implemented on board the satellites, in the near future. For the time being, dynamic bandwidth allocation capabilities (DBAC) provide a compromise solution when satellite systems are based on classical circuit switches, since the DBAC payload allows changing dynamically the capacity of each connection, without tear-down and set-up. We consider a DBAC satellite system and define algorithms to allocate the bandwidth so as to provide deterministic QoS guarantees. Standard dual leaky buckets (DLBs) regulate the traffic sources. We define bandwidth-handling policies, design connection admission control rules and evaluate the system performance analytically. Results show a significant increase in the bandwidth utilization of our system, when compared with a plain circuit switching solution