Systems and methods for protecting DSL systems against impulse noise

A method in an xDSL system, the method comprising:

• classifying a plurality of packets as retransmit eligible or non-transmit eligible;
• queuing packets classified as retransmit eligible in a retransmit queue;
• receiving a retransmit request and performing one of:
• sending a retransmit response if the received retransmit request is for packets classified as retransmit eligible;
• and
• sending a retransmit denial if the received retransmit request is for packets classified as non-transmit eligible or is for packets not present in the retransmit queue,
• wherein retransmission is performed above a gamma interface of the xDSL system, the gamma interface being an interface above a transmission protocol layer.

A method in an xDSL system, the method comprising;

• storing received packet data fragments in a receiver queue;
• determining whether the received packet data fragments belong to a protected channel or an unprotected channel based on whether a lower processing layer supports multiple channels;
• sending retransmission requests based on the presence of one or more of the following:
• missing sequence identification (SID) numbers;
• and
• corrupted packets, wherein corrupted packets are determined based on a cyclic redundancy check (CRC);
• and
• sending more than one retransmission request if a response is not received within a predetermined roundtrip time,
• wherein retransmission is performed above a gamma interface of the xDSL system, the gamma interface being an interface above a transmission protocol layer.

A protection module in a central office (CO) or a customer premise equipment (CPE) in an xDSL system configured to mitigate the effects of noise, comprising:

• a forward error correction (FEC) module comprising a Reed-Solomon (RS) encoder-decoder and an interleaver-deinterleaver;
• and
• a retransmission module configured to provide retransmission of corrupted data fragments within the data stream, wherein the FEC module mitigates a first noise and the retransmission module mitigates a second noise,
• wherein retransmission is performed above a gamma interface of the xDSL system, the gamma interface being an interface above a transmission protocol layer.