A data communications system includes a controller device and multiple client devices in data communications with each other over a data communications network. The controller device is configured to issue an instruction to a portion of the client devices that instructs them to acquire an interference characteristic associated with one or more external interference source. The interference characteristic may be measured interference magnitudes associated with a frequency of data communications over the data communications link. The portion of client devices transmits the measured interference magnitudes to the controller device. The controller device then determines a location of one or more interference sources based on the transmitted data.