The authors describe the networking emulation capability developed for the US Army Strategic Defense Command by the test environment support system enhancement (TESSE) program. This program supports the developmental efforts of the Battle Management/Command, Control, and Communications Element (BM/C3) for the Strategic Defense Initiative. This network emulation capability, referred to as the network emulator, is being used to test, in real time, candidate networking protocols, communications resource control algorithms, network management techniques, and data link/physical link layer representations in an end-to-end fashion; thus knitting together networking configuration items with the Command and Control applications which normally provide these items with control and the physical media which introduces anomalous stimuli.ETX