Methods and apparatus providing advanced classification for power over ethernet
AssigneeCisco Technology, Inc.
InventorsRoger A. Karam, Chad M. Jones, Frederick Roland Schindler
Life of this patent
Estimating the term…
Abstract
A system conducts a plurality of cycles on the powered device. Each cycle has a detection phase and a classification phase. A classification voltage is applied to the conductors during each cycle. The system measures a current in the conductors while the classification voltage is applied. The system determines a final class responsive to a plurality of measured currents. The final class utilized to determine an amount of inline power to deliver to the powered device.
Claims15
A method for classifying power sourcing equipment coupled to a powered device, the powered device configured to receive inline power from the power sourcing equipment in a wired network having at least two pairs of conductors coupling the powered device and the power sourcing equipment, the method comprising:
- detecting a classification process on the at least two pairs of conductors of the powered device, the process comprising a detection phase, a classification phase, and a signature phase following the classification phase;
- a classification phase voltage being detected on the conductors during the classification phase, and wherein a current is drawn from the conductors while the classification voltage is detected;
- a signature phase voltage being detected on the conductors during the signature phase, and wherein a magnitude of the signature phase voltage has an upper bound below a lower bound of a magnitude of the classification voltage and a lower bound above a magnitude of a reset level of the powered device;
- and
- identifying a type of the power sourcing equipment based on the signature phase voltage.
A powered device adapted to operate in conjunction with coupled power sourcing equipment so that the powered device can receive inline power from the power sourcing equipment in a wired network having at least two pairs of conductors coupling the powered device and the power sourcing equipment, the powered device comprising:
- circuitry responsive to a classification process on the at least two pairs of conductors, the process having a detection phase, a classification phase, and a signature phase following the classification phase, wherein the process is generated by the power sourcing equipment, and the circuitry configured to:
- present a current over the conductors to the power sourcing equipment responsive to a classification voltage applied during the classification phase of the process,
- detect a signature phase voltage on the conductors during the signature phase, wherein a magnitude of the signature phase voltage has an upper bound below a lower bound of a magnitude of the classification voltage and a lower bound above a magnitude of a reset level of the powered device, and
- identify a type of the power sourcing equipment based on the signature phase voltage.
A system comprising:
- a power sourcing equipment;
- a powered device;
- a wired network having at least two pairs of conductors coupling the powered device and the power sourcing equipment;
- and
- a memory on the powered device, the memory is encoded with a power source equipment classifying application that when executed on a processor configures the processor to perform an operation for classifying the power source equipment, the operation including:
- detecting a classification process on the at least two pairs of conductors coupled to the powered device, the process having a detection phase, a classification phase, and a signature phase following the classification phase;
- a classification voltage being detected on the conductors during the classification phase, and wherein a current is drawn from the conductors while the classification voltage is detected;
- a signature phase voltage detected on the conductors during the signature phase, and wherein a magnitude of the signature phase voltage has an upper bound below a lower bound of a magnitude of the classification voltage and a lower bound above a magnitude of a reset level of the powered device;
- and
- identifying a type of the power sourcing equipment based on the signature phase voltage.
Dependencies are inferred from the claim text.