Patent ID: 8724994

Claim:
An apparatus comprising: an optical line terminal (OLT) configured to couple to a plurality of optical network units (ONUs) and transmit a plurality of downstream frames to the ONUs, wherein each of the downstream frames comprises a plurality of forward error correction (FEC) codewords and a plurality of additional non-FEC encoded bytes that comprise synchronization information, wherein the plurality of additional non-FEC encoded bytes are partially protected by Header Error Control (HEC) code and partially not protected by the HEC code, wherein the downstream frame is a 10 gigabit passive optical network transmission container (XGTC) frame that comprises a downstream Physical Synchronization Block (PSBd) and a XGTC payload, wherein the PSBd comprises 24 non-FEC encoded bytes, wherein the PSBd comprises the synchronization information, and wherein the XGTC payload comprises the FEC codewords.