Performance evaluations on a bandwidth on demand algorithm for a high capacity multimedia satellite network

There are many system proposals for satellite-based multimedia communications that promise high capacity and ease of access. Many of these proposals require advanced switching technology and signal processing on-board satellites that will directly impact their cost, performance, availability, and time-to-market. Given the amount of commercial and technical risk involved in such complex systems, satellite operators have been looking for solutions that are simpler, yet flexible. One solution is based on a geosynchronous (GEO) satellite system equipped with simple on-board processing and switching. The satellite network is ATM-based and carries heterogeneous traffic. An important feature of this system is allowing for a maximum number of simultaneous users, hence, requiring effective connection admission control (CAC) and bandwidth on demand (BOD) algorithms. Nortel Networks has already developed an innovative CAC and BOD algorithm for the system. We present the BOD performance evaluations of the integrated algorithm. By detailed simulations, we show that the BOD scheme is able to efficiently utilize all available bandwidth and to gain high throughput. We also find that the end-to-end delays for voice traffic in the system falls well within the ITU´s QoS specification for GEO-based satellite systems. The application buffer sizes observed in the simulations can serve as a guideline for ground station and satellite on-board memory design