Abstract: In one embodiment, a device for communicating over a digital-subscriber-line (DSL) link comprises a digital-subscriber-line transceiver to transmit and receive data over the DSL link and a controller coupled to the digital-subscriber-line transceiver. The controller controls a non-intrusive adjustment of a transmitter that communicates over the DSL link.

Abstract: In one embodiment, a first device for communicating over a digital-subscriber-line (DSL) line comprises a digital-subscriber-line transceiver to transmit and receive data over the DSL link. A set of one or more performance parameters are associated with the DSL link by which the quality of the DSL link can be determined. The first device further comprises a controller coupled to the digital-subscriber-line transceiver. The controller causes a non-intrusive transmitter adjustment operation to be performed by the digital-subscriber-line transceiver.

Abstract: The present invention relates to a method and apparatus for testing components in ATM networks utilizing loop-back based ATM layer testing. The method and apparatus utilize interfaces and identifier codes to send and loop-back test cells along portions of virtual channels to test the virtual channels.

Abstract: A central office line unit (COLU) for a pulse code modulation (PCM) upstream and downstream system in a universal digital loop carrier (UDLC) includes a hybrid circuit for transmitting/receiving an analog signal to/from a switch. An analog-to-digital converter is provided for receiving the analog signal from the hybrid circuit and converting the analog signal to a converted digital signal. A digital transmission circuit transmits/receives a digital signal to/from a remote terminal. A quantizer is provided for evaluating and processing the converted digital signal so that only valid states of the converted digital signal are transmitted to the digital transmission circuit for transmission to the remote terminal. A receiver is used for receiving the digital signal from the digital transmission circuit and for evaluating and processing the digital signal so that only valid states of the digital signal are outputted from the receiver.