VALIDATING FUTURE OPERATIONAL COMMUNICATIONS TECHNIQUES - THE ATM TESTBED

ESA's spacecraft and payload operations support networks are facing ra pidly increasing demands for network bandwidth, induced by the require ments for the Columbus Orbital Facility and by Earth-observation proje cts like Envisat. The traditional implementation of operational networ ks is based on technologies that are adequate for lower data rates, bu t which become very expensive when rates of tens of megabits per secon d have to be supported. Since the traditional technologies permanently reserve the bandwidth of the maximum data rate of bursty traffic, the se resources generate costs even during trafficless intervals. The new Asynchronous Transfer Mode (ATM) technology has the potential to resp ond to such shortcomings in today's systems and to meet tomorrow's com munications requirements in a very cost-efficient way.