Test instrument for testing asymmetric digital subscriber lines

Abstract

A method of testing ADSL (asymmetric digital subscriber line) circuits is provided. A test instrument is connected to the customer premises end of the ADSL circuit, consisting of an ATU-C modem on the central office end and an ATU-R modem on the customer premises end, with a twisted-pair telephone line connecting the ATU-R and ATU-C modems. A remote test instrument is coupled to the ATU-C modem, typically on a semi-permanent basis in the central office, dedicated for testing multiple ADSL circuits by communicating with multiple ATU-C modems via a switch or router. The test instrument and remote test instrument communicate with each other in full duplex via the ADSL circuit using Internet Protocol (IP) data packets. The test instrument generates the upstream data traffic, controls the test sequence, and controls and coordinates the throughput test with the remote test instrument. The remote test instrument sends the downstream data traffic and returns the results of the throughput test in the form of frame counts from its end of the ADSL circuit back to the test instrument at end of the test sequence. The results from the upstream and downstream throughput tests are then visually displayed to the user of the test instrument.

Dependencies are inferred from the claim text.