Power delivery over ethernet cables

• US 20050268120A1
• Filed: 05/13/2004
• Published: 12/01/2005
• Est. Priority Date: 05/13/2004
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Schindler, Frederick R., Diab, Wael William
• Granted Patent: US 7,603,570 B2
• Time in Patent Office: Days
• US Class Current: 713/300
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: G06F 16/9537 Spatial or temporal dependent retrieval, e.g. spatiotemporal queries
• CPC Class Codes: H04L 12/10 Current supply arrangements
• CPC Class Codes: Y10S 707/99937 Sorting

Abstract

A method for power delivery comprises coupling an Ethernet cable comprising four wire pairs to a power delivery system and providing power to a powered device on all of the wire pairs. A power delivery system includes an interface operable to couple to an Ethernet cable comprising four wire pairs and a controller operable to provide power to a powered device on all of the wire pairs.

Claims

1. A method for power delivery, comprising:

coupling an Ethernet cable comprising four wire pairs to a power delivery system; and

providing power to a powered device on all of the wire pairs.

2. The method of claim 1, further comprising:

determining that the powered device requires less power; and

reducing the number of wire pairs on which power is provided.

3. The method of claim 1, wherein:

the method further comprises determining a power requirement for the powered device; and

providing the power on all of the wire pairs is performed in response to determining that the power requirement for the powered device exceeds a predetermined amount.

4. The method of claim 3, wherein the power requirement is determined based on power information received from the powered device.

5. The method of claim 4, wherein the power information is communicated using a network discovery protocol.

6. The method of claim 5, wherein the network discovery protocol is Cisco Discovery Protocol (CDP).

7. The method of claim 4, wherein the power information is communicated using a side protocol associated with a power delivery protocol.

8. The method of claim 4, wherein the power information is communicated using a power delivery protocol.

9. The method of claim 1, further comprising:

detecting a change in power usage for the powered device; and

adjusting the power level provided on the wire pairs in response to detecting a change in the power usage for the powered device.

10. The method of claim 9, wherein:

the powered device is a docking station; and

the change in power usage results from a docked device being removed from the docking station.

11. The method of claim 9, wherein the powered device is a network device operable to consume at least a portion of power, and further comprising providing, from the powered device, a level of power to another powered device coupled to the powered device.

12. The method of claim 1, wherein:

the powered device is coupled to the Ethernet-grade cable using a plurality of power couplers; and

the power couplers each comprise at least one resistor operable to regulate current flow through the associated power coupler.

13. A power delivery system, comprising:

an interface operable to couple to an Ethernet cable comprising four wire pairs; and

a controller operable to provide power to a powered device on all of the wire pairs.

14. The system of claim 13, wherein the controller is further operable to:

determine that the powered device requires less power; and

reduce the number of wire pairs on which power is provided.

15. The system of claim 13, wherein:

the controller is further operable to determine a power requirement for the powered device; and

the controller provides the power on all of the wire pairs in response to determining that the power requirement for the powered device exceeds a predetermined amount.

16. The system of claim 15, wherein the power requirement is determined based on power information received from the powered device.

17. The system of claim 15, wherein the power information is communicated using a network discovery protocol.

18. The system of claim 17, wherein the network discovery protocol is Cisco discovery protocol (CDP).

19. The system of claim 15, wherein the power information is communicated using a side protocol associated with a power delivery protocol.

20. The system of claim 15, wherein the power information is communicated using a power delivery protocol.

21. The system of claim 13, wherein the controller is further operable to:

detect a change in power usage for the powered device; and

adjust the power level provided on the wire pairs in response to detecting a change in the power usage for the powered device.

22. The system of claim 21, wherein:

the powered device is a docking station; and

the change in power usage results from a docked device being removed from the docking station.

23. The system of claim 21, wherein:

the powered device is a computer; and

the change in power usage results from the computer being removed from the interface.

24. The system of claim 13, wherein:

the powered device is coupled to the Ethernet cable using a plurality of power couplers; and

the power couplers each comprise at least one resistor operable to regulate current flow through the associated power coupler.

25. The system of claim 13, wherein the interface comprises a plurality of ports each coupled to a particular one of the wire pairs, and the controller is operable to provide power on more than one of the ports.

26. The system of claim 13, wherein the interface comprises a port coupled to more than one wire pair, and the controller is operable to provide power through the port.

27. A power delivery system, comprising:

means for coupling an Ethernet cable comprising four wire pairs to a power delivery system; and

means for providing power to a powered device on all of the wire pairs.