Besides testing the Paragons directly connected with ATM, Pratt and Jackson have devised several different test configurations for the ATM. For each configuration, message-passing benchmarks, PVM, and applications over ATM will be tested. The tests will verify operation of the ATM over a FORE ATM/OC12c switch. Configuration 2 will test the switching the OC12 onto an OC3 backbone. (OC3 is likely to be used for inter-site tests.) Additional OC3 interfaces may be used to provide additional buffering. In the last two configurations delay and errors are introduced with a BBN long-link emulator to simulate cross-country OC3 performance.