This Outline of Investigation describes the requirements used to evaluate the transmission performance of high speed cable assemblies. Four types of cable assemblies are covered by these requirements: a) Wire-only cables that contain no circuit component. b) Passive cables that contain only passive circuit components. c) Active cables that contain active equalization circuit components with equalizer functions but do not have converting@ transmitting or receiving functions. d) Active cables that contain active circuit components that convert or amplify the signals and also contain transmit and receive functions.