Test and analysis of low data rate ATM over SATCOM

Asynchronous transfer mode (ATM) and satellite communications (SATCOM) complement one another. Together they can provide an efficient and effective communications infrastructure capable of supporting global interconnectivity and mobility. Wide area satellite coverage provides connectivity to remote locations and mobile users. The speed and flexibility of ATM support real-time and bandwidth-demanding communications services. ATM also enables scalable, flexible and on-demand resource allocation and facilitates the seamless integration of LAN and wide area networks (WAN) into global area networks (GAN). An ATM-SATCOM research and demonstration programme has been initiated within the Communications Division of the SHAPE Technical Centre (STC). The goal is to demonstrate the viability and utility of low data rate ATM operation over NATO SATCOM at E1 2.048 Mbps and lower rates. Two key issues are addressed: rate conversion and performance of ATM protocols over SATCOM. The data rate is reduced by filtering out the idle cells so that only the useful information bearing cells are passed over the satellite link. The performance of the ATM. Protocol over the higher error rate, longer delay and delay variation satellite communication channel is examined and the results of initial measurements via simulator and live satellite link are presented. It is shown that for operation of TCP/IP over a low rate ATM cell relay using commercial satellite modems is viable.