Patent ID: 7519124

Claim:
A method of mitigating a communication lag time variation in a DSL communication system, caused by a first DSL modem, comprising, interspersing dummy data with a variable bit rate first data stream to form a combined data stream, using hardware; supplying the first data stream to an electronic subsystem of the first DSL modem; wherein a rate at which the dummy data is supplied increases in response to a decrease in the bit-rate for the first data stream; whereby an increase in the communication lag time resulting from the decrease in the bit-rate is mitigated or avoided by the addition of the dummy data; transmitting the combined data stream over a line; and separating the first data stream from the combined data stream; whereby the first data stream is recovered and the dummy data is discarded following transmission over the line; wherein the electronic communication system uses frequency division duplexing and at least part of the dummy data is selectively transmitted on different frequencies from data of the first data stream; and wherein an error rate for transmission at the frequencies at which only dummy data is transmitted is allowed to be much greater than an error rate at the frequencies at which data of the first data stream is transmitted.