Optical line termination in a passive optical network

A passive optical line termination device comprising:

• a) a system-on-a-chip (SoC) subsystem comprising:
• i) a time-insensitive SoC processor, wherein:
• a transmission comprises a transmission convergence frame (TCF) format having 1) a TCF overhead field and 2) a TCF payload field, and
• the SoC processor is adapted to execute functions related to the TCF payload field separated from the TCF overhead field, and
• ii) a memory interface operatively coupled to the SoC processor;
• b) a memory operatively coupled to the memory interface;
• and
• c) a time sensitive integrated circuit comprising:
• i) a distributed direct memory access engine operatively coupled to the time-insensitive SoC processor and the memory interface, wherein:
• the distributed direct memory access engine is adapted to interconnect the integrated circuit with the SoC sub-system and to directly access the memory, and
• the distributed direct memory access engine comprises:
• a system-on-a-chip (SoC) interface;
• a first direct memory access engine operatively coupled to the SoC interface to read a TCF payload field from the memory;
• and
• a second direct memory access engine operatively coupled to the SoC interface to write a TCF payload field to the memory;
• ii) a transmitter operatively coupled to the first direct memory access engine, wherein the transmitter is adapted to combine a downstream TCF payload field with a downstream TCF overhead field into a downstream transmission;
• iii) a receiver operatively coupled to the second direct memory access engine, wherein the receiver is adapted to separate an upstream TCF payload field from an upstream TCF overhead field;
• and
• iv) an internal processor operatively coupled to the transmitter and the receiver, wherein the internal processor is adapted to:
• control the time sensitive integrated circuit;
• process received sub-fields within the upstream TCF overhead field in a time-sensitive manner separated from a received upstream TCF payload field prior to offloading the received upstream TCF payload field to the time-insensitive SoC processor;
• assemble a downstream TCF overhead field prior to combination with a downstream TCF payload field into a downstream transmission;
• and
• control processing of the downstream overhead field using information obtained from processing the received upstream TCF overhead field without offloading all of the received data retrieval and reconstruction to the time-insensitive SoC processor.