Inline power for multiple devices in a wired data telecommunications network

• US 7,664,136 B2
• Filed: 06/02/2005
• Issued: 02/16/2010
• Est. Priority Date: 06/02/2005
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Li, Ping, Toebes, John Albert, Cham, Jack C.
• Primary Examiner(s): Ferris; Derrick W
• Assistant Examiner(s): LEVELLE, JASON C
• Application Number:
  US11/144,094
• Publication Number:
  US 20060273661A1
• Time in Patent Office: 1,720 Days
• Field of Search: 370/463, 713/310
• US Class Current: 370/463
• CPC Class Codes: G06F 1/266 Arrangements to supply power to external peripherals either directly from the computer or under computer control, e.g. supply of power through the communication port, computer controlled power-strips
• CPC Class Codes: H04L 12/10 Current supply arrangements
• CPC Class Codes: H04L 25/0278 Arrangements for impedance matching

Abstract

A power sourcing equipment-powered device (PSE-PD) combination unit requests inline power from a connected PSE or other PSE-PD combination unit by having the PD portion of the PD-PSE combination unit adapt its electrical characteristics, if necessary, to obtain the maximum power available. The PD-PSE combination device keeps track of available power less power consumed locally with a summation unit. A PSE manager unit grants PD power requests from downstream devices based upon the available power left (e.g., original PSE power less losses less local consumption).

Claims

1. An inline power device, comprising:

a first port configured as a powered device (PD) port for coupling power and data with a port of an external power sourcing equipment (PSE), the first port facilitating a power negotiation with the port of the external PSE;

a plurality of selectable electrical components for use in establishing a magnitude of a power request from the external PSE, said selectable electrical components being selected as a function of said power negotiation;

a summation unit configured to;

receive a power level from the PSE via the first port in response to the power negotiation with the external PSE, the power level representing a total amount of power provided to the inline power device by the PSE,

detect a power consumption level associated with the inline power device, the power consumption level associated with an amount of power utilized by the inline power device during operation, and

detect an available power level for use by a downstream coupled PD based upon a difference between the power level and the power consumption level;

a second port configured as a PSE port for coupling available power and data with a port of a downstream coupled PD; and

a PSE manager unit configured for receiving inline power requests from a downstream coupled PD and responsive to the summation unit for providing up to the available power level to the downstream coupled PD.

2. The device of claim 1, wherein the plurality of selectable electrical components are a plurality of selectable resistors.

3. The device of claim 1 wherein said first port and said second port are Ethernet ports.

4. The device of claim 2 wherein said first port and said second port are Ethernet ports.

5. The device of claim 1, further comprising:

circuitry for selecting one of the plurality of selectable electrical components, wherein said circuitry is configured to first select a component corresponding to a request for a maximum amount of power.

6. The device of claim 5, wherein said circuitry is configured to second select a component corresponding to a request for a less than maximum amount of power upon denial of the first request.

7. The device of claim 6, wherein the plurality of selectable electrical components are a plurality of selectable resistors.

8. The device of claim 7 wherein said first port and said second port are Ethernet ports.

15. The device of claim 1, wherein the PSE manager unit is configured to provide up to the available power level to a set of downstream daisy chained PD.

18. The device of claim 1, wherein the inline power device is configured to consume power up to the power consumption level provided to the inline power device by the external PSE.

19. The device of claim 1, wherein:

when facilitating a power negotiation with the port of the external PSE, the first port is configured to present the plurality of selectable electrical components to the external PSE, the inline power device configured as an IEEE 802.3af standard compliant device and the external PSE configured as an IEEE 802.3af standard compliant device; and

the second port, configured as a PSE port, is configured to receive a downstream power negotiation request from the downstream coupled PD and is configured to provide an available amount of power, based upon the downstream power negotiation request, and data to the downstream coupled PD, the downstream coupled PD configured as an IEEE 802.3af standard compliant device.

20. The device of claim 19, further comprising:

a PD component disposed in electrical communication with the first port, the PD component configured to negotiate power with the external PSE via the first port, based upon the plurality of selectable electrical components; and

wherein the PSE manager unit is disposed in electrical communication with the second port, the PSE manager unit, when receiving inline power requests from a downstream coupled PD, is configured to receive downstream a power negotiation request from the downstream coupled PD via the second port, the PSE manager unit configured to one of grant the downstream power negotiation request from the downstream coupled PD up to the available power level or reject the downstream power negotiation request based upon the available power level for use by the downstream coupled PD as detected by the summation unit.

9. A method for providing inline power, comprising:

coupling a first port configured as a powered device (PD) port of a powered device-power sourcing equipment (PD-PSE) combination device to a PSE-configured port of a first external device;

coupling a second port configured as a PSE port of the PD-PSE combination device to a PD-configured port of a second external device;

selectively requesting, by way of a negotiation through the PD port and beginning with a maximum value, power at the first port from the first external device;

receiving a negotiated power level from the first external device via the first port in response to the power negotiation with the first external device, the negotiated power level representing a total amount of power provided by the first external device;

detecting a power consumption level associated with the PD-PSE combination device, the power consumption level associated with an amount of power utilized by the PD-PSE combination device during operation;

detecting an available power level for use by the downstream coupled second external based upon a difference between the negotiated power level and the power consumption level;

consuming power up to the power consumption level, by the PD-PSE combination device, provided by the first external device; and

providing available power up to the available power level, received from the first external device by the PD-PSE combination device, to the second external device.

10. The method of claim 9, further comprising:

receiving a request for inline power from a downstream-coupled PD at the second port; and

accepting the request for inline power from the downstream-coupled PD if the request is for an amount of power not exceeding the power available.

11. The method of claim 9, further comprising:

receiving a request for inline power from a downstream-coupled PD at the second port; and

denying the request for inline power from the downstream-coupled PD if the request is for an amount of power exceeding the power available.

12. The method of claim 9, further comprising:

receiving a request for inline power from a downstream-coupled PD at the second port;

accepting the request for inline power from the downstream-coupled PD if the request is for an amount of power not exceeding the power available; and

denying the request for inline power from the downstream-coupled PD if the request is for an amount of power exceeding the power available.

13. The method of claim 12, further comprising:

requesting subsequently, responsive to a denial of the initial request, a less than maximum available power at the first port from the first external device.

16. The method of claim 9, wherein providing available power up to the available power level, received from the first external device by the PD-PSE combination device, to the second external device comprises providing available power up to the available power level, received from the first external device by the PD-PSE combination device, to a set of downstream daisy chained second external devices.

14. An apparatus for providing inline power, comprising:

means for coupling a first port configured as a powered device (PD) port of a powered device-power sourcing equipment (PD-PSE) combination device to a PSE-configured port of a first external device;

means for coupling a second port configured as a PSE port of the PD-PSE combination device to a PD-configured port of a second external device;

means for selectively requesting, by way of a negotiation through the PD port and beginning with a maximum value, power at the first port from the first external device;

means for receiving a negotiated power level from the first external device via the first port in response to the power negotiation with the first external device, the negotiated power level representing a total amount of power provided by the first external device;

means for detecting a power consumption level associated with the PD-PSE combination device, the power consumption level associated with an amount of power utilized by the PD-PSE combination device during operation;

means for detecting an available power level for use by the downstream coupled second external based upon a difference between the negotiated power level and the power consumption level;

means for consuming power up to the power consumption level, by the PD-PSE combination device, provided by the first external device; and

means for providing available power up to the available power level, received from the first external device by the PD-PSE combination device, to the second external device.

17. The apparatus of claim 14, wherein means for providing available power up to the available power level, received from the first external device by the PD-PSE combination device, to the second external device comprises means for providing available power up to the available power level, received from the first external device by the PD-PSE combination device, to a set of downstream daisy chained second external devices.