Abstract: A method and apparatus for determining and displaying the throughput rate of a modem that includes a first housing, first circuitry disposed within the first housing for demodulating data received by the modem and modulating data transmitted by the modem, and a first port for outputting demodulated data from the modem and inputting data to the modem for modulating. A counting device is connected between the modem and connected equipment. The counting device includes second circuitry for monitoring traffic between second and third ports and generating the throughput rate in accordance with the monitoring. The counting device displays an indication of the throughput rate to a user of the connected equipment.

Abstract: The present invention provides methods and apparatus for transmitting a data-bearing signal and a non-data-bearing signal. One embodiment comprises communicatively coupling a data-bearing signal during a first time period and communicatively coupling a non-data-bearing signal during a second time period. The data-bearing signal has a first PSD. The non-data-bearing signal has a second PSD substantially the same as the first over a range of frequencies. The non-data-bearing signal has characteristics facilitating echo cancellation. Another embodiment comprises a line interface and a transmitter coupled to the line interface, comprising a data encoder and a periodic signal generator. The encoder is configured to produce a data-bearing signal with a first PSD. The periodic signal generator is configured to produce a non-data-bearing signal with a second PSD. The second PSD is substantially the same as the first PSD over a first range of frequencies.