Apparatus and method for communicating FEC mode and alarming mismatch
View Patent ↗A multi-mode transmission unit processes data to form an error correction code in accordance with one of a plurality of selectable processes. The data, correction code and a process identifier can be transmitted to a receiving unit which can carry out error correction of the data in accordance with the identified process.
1. An apparatus comprising:
an optical transmitter which transmits a frame sequence where each frame of the frame sequence has a forward error correction (FEC) coded portion wherein the FEC coded portion uses a reserved optical transport unit (OTU) byte to encode a FEC mode, the transmitter incorporates multi-mode error correction circuits that create no error correction in a first mode, a first error correction code sequence in accordance with received data in a second mode and a second error correction sequence in accordance with received data in a third mode and a pre-selected error correction mode indicator, said correction mode indicator having a first value in the first mode, a second value in the second mode and a third value in the third mode; and
the optical transmitter includes data transmission elements that transmit at least the code sequence and error correction mode indicator incorporated into the OTU byte of each of the respective frames of the frame sequence.
2. An apparatus as in claim 1 which includes: a receiver responsive to a received error correction code sequence, and error correction mode, includes circuitry that corrects errors in received data in accordance therewith.
3. An apparatus as in claim 2 where the transmitter includes a plurality of substantially identical multi-mode error correction circuits and respective data transmission elements, the data transmission elements are each associated with a respective transmission wavelength.
4. An apparatus as in claim 2 where the transmitter and receiver are linked by at least one of a fiber optic transmission medium, or, a wireless electro-magnetic transmission medium.
5. An apparatus as in claim 2 where the transmitter includes framing circuitry.
6. An apparatus as in claim 5 where the framing circuitry processes incoming data to form transmission frames each having a payload data section, an error correction mode indicating section and an error correction code section.
7. An apparatus as in claim 6 where the date transmission elements of the transmitter serialize and transmit the frames to the receiver via a predetermined medium.
8. An apparatus as in claim 6 where the receiver circuitry includes framing circuitry, and error correction circuitry, responsive to a received error correction mode indicator, to process and correct received payload data.
9. An apparatus as in claim 8 where the receiver associates another error correction code with corrected received payload data.
10. An apparatus as in claim 2 where the receiver includes an error mode alarm indicator.
11. An apparatus as in claim 1 where the transmitter includes error correction mode specifying circuitry.
12. A method comprising:
multi-mode error correction circuits creating a payload including received data with no error correction in a first mode, a first error correction code sequence in accordance with received data in a second mode and a second error correction sequence in accordance with received data in a third mode in accordance with a pre-selected error correction mode indicator, said correction mode indicator having a first value in the first mode, a second value in the second mode and a third value in the third mode;
a processor providing the pre-selected error correction mode indicator; and
an optical transmitter that transmits a frame sequence where each frame of the frame sequence has a forward error correction (FEC) portion wherein the FEC portion uses a reserved optical transport unit (OTU) byte to encode a FEC mode, the transmitter includes data transmission elements transmitting the payload within the respective frames of the frame sequence including at least the code sequence and error correction mode indicator of the OTU byte on a frame by frame basis.
13. The method as in claim 12 further comprising selecting an error correction mode via an input to the processor.
14. The method as in claim 12 where transmitting includes optically transmitting the sequences.
15. The method as in claim 14 where optically transmitting includes modulating an optical signal of a selected wavelength.
16. The method as in claim 15 which includes determining the error correction mode of a received sequence.
17. The method as in claim 16 which includes processing the received data sequence in accordance with the determined error correction mode.
18. The method as in claim 16 where determining precedes processing the data sequence.
19. The method as in claim 16 where determining precedes processing the error correction code sequence.
20. The method as in claim 16 which includes issuing an alert in response to determining the error correction mode.
21. The method as in claim 15 where the data and the mode sequence are transmitted prior to transmitting the error correction code sequence.