Transmission of pulse power and data over a wire pair
In one embodiment, a method includes applying Forward Error Correction (FEC) to data at power sourcing equipment, transmitting the data and pulse power over a wire pair to a powered device, identifying data transmitted during power transitions between a pulse power on time and a pulse power off time in the pulse power at the powered device, and applying FEC decoding to at least a portion of the data based on said identified power transitions.
1. A method comprising:
applying Forward Error Correction (FEC) to data at power sourcing equipment;
transmitting the data and pulse power over a wire pair to a powered device, the pulse power comprising a pulse power on time and a pulse power off time;
identifying power transitions between the pulse power on time and the pulse power off time in the pulse power at the powered device;
marking data transmitted during the power transitions to identify errors for decoding; and
applying FEC decoding to at least a portion of the data that is transmitted during the power transitions.
2. The method of claim 1 further comprising suspending transmission of the data during power transitions at the power sourcing equipment, buffering the data transmitted during said power transitions at the powered device, and decoding the FEC for remaining data.
3. The method of claim 1 further comprising modulating pulses of the pulse power at the power sourcing equipment for use in transmitting control plane data to the powered device.
4. The method of claim 1 wherein the pulse power on time comprises a high voltage state and the pulse power off time comprises a low voltage state.
5. The method of claim 4 wherein the data is transmitted only during the pulse power on time.
6. The method of claim 1 wherein the FEC mitigates corruption of Ethernet packets during said power transitions.
7. The method of claim 1 wherein said power transitions each comprise an approximately 0.5 millisecond time window and wherein the pulse power on time is greater than the pulse power off time.
8. The method of claim 1 wherein identifying said power transitions comprises identifying said power transitions at a controller at the powered device, wherein the controller is coupled to a wire pair receiving the data and the pulse power.
9. The method of claim 1 further comprising performing fault sensing during a low voltage startup before transmitting the pulse power and between high power pulses in the pulse power.
10. The method of claim 1 further comprising monitoring an FEC error rate; identifying a fault on a wire based on an increase in the FEC error rate; and shutting down the pulse power.
11. A powered device comprising:
an interface configured to receive pulse power and data from power sourcing equipment over a wire pair, the pulse power comprising a pulse power on time and a pulse power off time; and
a controller coupled to the wire pair and configured to perform operations including:
identifying power transitions between a pulse power on time and a pulse power off time in the pulse power;
marking data transmitted during the power transitions to identify errors for decoding; and
applying Forward Error Correction (FEC) decoding to at least a portion of the data that is transmitted during the power transitions to mitigate corruption of the data during said power transitions.
12. The powered device of claim 11 wherein the data is suspended during power transitions at the power sourcing equipment and the controller is buffers the data transmitted during said power transitions at the powered device and performs FEC decoding for remaining data.
13. The powered device of claim 11 wherein locations of said power transitions are used to mark a location of symbols in the data that are potentially in error and wherein the controller comprises an erasure-correcting decoder to decode the symbols in the data whose locations have been marked.
14. The powered device of claim 11 wherein the data is transmitted only during said pulse power on time.
15. The powered device of claim 11 wherein fault sensing is performed during a low voltage startup before the pulse power is transmitted to the powered device and between high power pulses in the pulse power.
16. The powered device of claim 11 , wherein the power transitions each comprise an approximately 0.5 millisecond time window and wherein the pulse power on time is greater than the pulse power off time.
17. A system comprising:
power sourcing equipment operable to transmit data and pulse power and apply Forward Error Correction (FEC) to the data, the pulse power comprising a pulse power on time and a pulse power off time;
a powered device that receives the data and the pulse power from the power sourcing equipment over a wire pair; and
a controller at the powered device, the controller configured to perform operations including:
identifying power transitions between the pulse power on time and the pulse power off time in the pulse power;
marking data transmitted during the power transitions to identify errors for decoding; and
applying FEC decoding to at least a portion of the data that is transmitted during the power transitions to mitigate corruption of the data during said power transitions.
18. The system of claim 17 wherein the power sourcing equipment performs fault sensing during a low voltage startup before the pulse power is transmitted to the powered device and between high power pulses in the pulse power.
19. The system of claim 17 wherein locations of said power transitions are used to mark a location of symbols in the data that are potentially in error and wherein the controller comprises an erasure-correcting decoder to decode symbols in the data whose locations have been marked.
20. The system of claim 17 , wherein the controller is configured to further perform operations including:
monitoring an FEC error rate; and
identifying a fault on the wire pair based on an increase in the FEC error rate.