Abstract: A method and apparatus are provided for determining which path of a network transmission link having a receive path and a transmit path is carrying receive signals, and then automatically configuring a network tester such that an internal transmitter and an internal receiver match the transmit and receive paths of the network. Initially, both paths are monitored by the tester's receiver to determine whether there is traffic on the network. Then the tester automatically configures its interface to designate a first one of the paths as the receive path, and tests this configuration to determine whether the internal receiver receives a signal. If a signal is received, the configuration is verified. If no signal is received, the tester reconfigures the interface to designate the other path as the receive path. Once the network receive path is identified, the tester automatically configures its interface such that the transmit path is set opposite the receive path.