Method to improve latency in an ethernet PHY device

A method of operating a data communications device, the method comprising:

• receiving data via a network link of the data communications device using transceiver circuitry of the network link, wherein the received data includes data symbols encoded using trellis coded modulation (TCM);
• decoding the received encoded data symbols using maximum-likelihood (ML) decoding to map a received symbol sequence to an allowed symbol sequence using a trace-back depth, wherein a trace-back depth value is a number of symbols of delay used by decoder circuitry of the network link to identify the allowed symbol sequence from the received symbol sequence;
• determining length of a physical medium of the network link as a link statistic;
• and
• setting the trace-back depth value for the decoder according to one or more link statistics including the determined length.

A data communication apparatus comprising:

• means for receiving data via a network link, wherein the received data includes data symbols encoded using trellis coded modulation (TCM);
• means for decoding the received encoded data symbols using maximum-likelihood (ML) decoding to map a received symbol sequence to an allowed symbol sequence using a trace-back depth, wherein a trace-back depth value is a number of symbols of delay used by the ML decoding to identify the allowed symbol sequence from the received symbol sequence;
• means for determining length of a physical medium of the network link as a link statistic;
• and
• means for setting the trace-back depth value for the ML decoding according to to one or more link statistics including the determined length.