A testing system may include an electrical cable, a computing device, a communication interface, at least one downstream device, and testing software. The communication interface may be coupled to the electrical cable and to the computing device. The at least one downstream device may be coupled to the electrical cable. The testing software may be stored on the computing device. The testing software may be configured to initiate and evaluate transfer of data between the computing device and the at least one downstream device through the electrical cable and the communication interface.