Security protection of terabit ethernet pcs layer using alignment markers

An apparatus comprising:

• a transmit signal processor including a physical coding sublayer (PCS) configured to generate, from an input data stream, multiple lanes of a PCS signal, wherein the PCS is configured to:
• convert the data stream to a sequence of bit blocks;
• periodically insert into the sequence of bit blocks an alignment marker (AM) group including multiple individual alignment markers for respective ones of the multiple lanes;
• add security protection to each bit block according to a security protocol to produce a sequence of protected bit blocks;
• modify each AM group with security information to be used by the security protocol to remove the security protection added to the sequence of protected bit blocks;
• apply forward error correction to the sequence of protected bit blocks and the modified AM groups to produce forward error correction codewords;
• and
• produce the multiple lanes from the codewords;
• and
• an optical transmitter coupled to the transmit signal processor and configured to transmit optical signals representing the multiple lanes over an optical link.

A non-transitory computer readable medium encoded with instructions that, when executed by a processor of a transmitter, cause the processor to perform a method comprising:

• generating, from an input data stream, multiple lanes of a physical coding sublayer (PCS) signal, the generating including:
• converting the data stream to a sequence of bit blocks;
• periodically inserting into the sequence of bit blocks an alignment marker (AM) group including multiple individual alignment markers for respective ones of the multiple lanes;
• adding security protection to each bit block according to a security protocol to produce a sequence of protected bit blocks;
• modifying each AM group with security information to be used by the security protocol to remove the security protection added to the sequence of protected bit blocks;
• applying forward error correction to the sequence of protected bit blocks and the modified AM groups to produce forward error correction codewords;
• producing the multiple lanes from the codewords;
• and
• supplying data representing the multiple lanes to an optical transmitter to cause the optical transmitter to transmit optical signals representing the multiple lanes over an optical link.