Power management for serial-powered device connections

• US 20060100799A1
• Filed: 11/05/2004
• Published: 05/11/2006
• Est. Priority Date: 11/05/2004
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Karam, Roger A.
• Granted Patent: US 7,903,809 B2
• Time in Patent Office: Days
• US Class Current: 702/57
• CPC Class Codes: G06F 1/26 Power supply means, e.g. regulation thereof for memories G11C
• CPC Class Codes: G06F 1/28 Supervision thereof, e.g. detecting power-supply failure by out of limits supervision
• CPC Class Codes: G06F 1/3228 Monitoring task completion, e.g. by use of idle timers, stop commands or wait commands
• CPC Class Codes: H04L 12/10 Current supply arrangements
• CPC Class Codes: H04L 12/44 Star or tree networks

Abstract

A method and apparatus for managing an Inline Power relationship between and among a first network device acting as power sourcing equipment (PSE) to provide Inline Power to a second Powered Device (PD) and a third device. In one aspect of the invention, the powered device(s) and the third device are powered (at least in part) by the PSE using inline power from at least one port (which may include more than one PSE) and they are powered over one or more sets of cables.

Claims

1. A method for managing an inline power relationship between a first device, a second device and a third device in a wired data telecommunications network, the first device configured as power sourcing equipment (PSE), the second device having a first power requirement and configured as a powered device (PD) and coupled via at least a first pair of conductors to the first device, and the third device having a second power requirement and coupled via at least a second pair of conductors to the second device, the method comprising:

communicating from the third device to the second device a representation of a magnitude of the second power requirement;

calculating a representation of a combination of the first and second power requirements; and

communicating a representation of the combination to the first device.

2. The method of claim 1, wherein said communicating from the third device takes place over the at least a second pair of conductors.

3. The method of claim 1, wherein said communicating from the third device takes place over a wireless link.

4. The method of claim 1, wherein said calculating takes place at the second device.

5. The method of claim 1, wherein said communicating the representation of the combination takes place over the at least a first pair of conductors.

6. The method of claim 1, wherein said communicating the representation of the combination takes place over a wireless link.

7. The method of claim 1, further comprising:

storing a representation of the magnitude of the second power requirement in a first memory store of the second device.

8. The method of claim 1, further comprising:

storing a representation of the combination of the first and second power requirements in a memory store of the second device.

9. The method of claim 7, further comprising:

storing a representation of the combination of the first and second power requirements in a second memory store of the second device.

10. A method for managing an inline power relationship between a first device, a second device and a third device in a wired data telecommunications network, the first device configured as power sourcing equipment (PSE), the second device having a first power requirement and configured as a powered device (PD) and coupled via at least a first pair of conductors to the first device, and the third device having a second power requirement and coupled via at least a second pair of conductors to the second device, the method comprising:

determining the second power requirement;

calculating a representation of a combination of the first and second power requirements; and

communicating a representation of the combination to the first device.

11. The method of claim 10, further comprising:

storing a representation of the magnitude of the second power requirement in a first memory store of the second device.

12. The method of claim 10, further comprising:

storing a representation of the combination of the first and second power requirements in a memory store of the second device.

13. The method of claim 11, further comprising:

storing a representation of the combination of the first and second power requirements in a second memory store of the second device.

14. A method for providing inline power from a first device to a second device and a third device in a wired data telecommunications network, the method comprising:

coupling the first device and the second device with a first pair of conductors and a second pair of conductors;

tapping power from the first pair of conductors and the second pair of conductors to provide power to couple to the third device; and

interrupting power flow from the first and second pairs of conductors to the second device in response to current draw from the second device dropping below a predetermined threshold.

15. The method of claim 14, further comprising:

responding to a discovery signal with an identity network in order to obtain inline power.

16. The method of claim 14, further comprising:

providing power flow to said third device in response to a manual input signal.

17. The method of claim 14, further comprising:

providing power flow to said third device through a keyed connector.

18. A method for providing inline power from a first device to a second device and a third device in a wired data telecommunications network, the method comprising:

coupling the first device and the second device with at least a first pair of conductors;

tapping power from the at least first pair of conductors to power a controller; and

enabling inline power flow from the at least first pair of conductors to the second device in response to the second device responding to a discovery request from the control with a predetermined identity network.

19. The method of claim 18, further comprising:

interrupting inline power flow from the at least first pair of conductors to the second device in response to current draw from the second device dropping below a predetermined threshold.

20. An adapter for receiving data and inline power from a first connector adapted to be coupled to a port in a wired data telecommunications network and providing data and inline power to a second connector and power to a third connector, the adapter comprising:

a first connector for coupling the adapter to a power sourcing equipment (PSE) device of a wired data telecommunications network having at least two pairs of conductors;

a second connector for coupling the adapter to a second device;

a third connector for coupling the adapter to a third device;

a first power tap circuit coupled to a first of the at least two pairs of conductors for receiving a first direct current (DC) voltage;

a second power tap circuit coupled to a second of the at least two pairs of conductors for receiving a second DC voltage;

the difference between the first voltage and the second voltage being a difference voltage;

a controller coupled to receive the first voltage and the second voltage and to apply the difference voltage to an output circuit including the third connector.

21. The adapter of claim 20, wherein:

the output circuit includes a DC-DC converter for converting the difference voltage to another DC voltage.

22. The adapter of claim 20, wherein:

the output circuit contains only the third connector and conductors coupling the third connector to the controller.

23. The adapter of claim 20, wherein:

the output circuit includes a switch controlled by the controller and controlling whether or not power is available at the third connector.

24. The adapter of claim 20, further comprising:

a control in communication with the controller, activation of the control causing the controller to apply power to the third connector.

25. The adapter of claim 20, further comprising:

switches in line with each of the conductors of the at least two pairs of conductors, a state of the switches controlled by the controller so that the switches are closed if a device is coupled to the second connector and no power is being directed to the third connector.

26. The adapter of claim 20, further comprising:

switches in line with each of the conductors of the at least two pairs of conductors, a state of the switches controlled by the controller so that the switches are open if power is being delivered to the third connector and no powered device has been identified as coupled to the second connector.

27. An apparatus for managing an inline power relationship between a first device, a second device and a third device in a wired data telecommunications network, the first device configured as power sourcing equipment (PSE), the second device having a first power requirement and configured as a powered device (PD) and coupled via at least a first pair of conductors to the first device, and the third device having a second power requirement and coupled via at least a second pair of conductors to the second device, the apparatus comprising:

means for communicating from the third device to the second device a representation of a magnitude of the second power requirement;

means for calculating a representation of a combination of the first and second power requirements; and

means for communicating a representation of the combination to the first device.

28. The apparatus of claim 27, wherein said means for communicating from the third device takes place over the at least a second pair of conductors.

29. The apparatus of claim 27, wherein said means for communicating from the third device takes place over a wireless link.

30. The apparatus of claim 27, wherein said means for calculating takes place at the second device.

31. The apparatus of claim 27, wherein said means for communicating the representation of the combination takes place over the at least a first pair of conductors.

32. The apparatus of claim 27, wherein said means for communicating the representation of the combination takes place over a wireless link.

33. The apparatus of claim 27, further comprising:

means for storing a representation of the magnitude of the second power requirement in a first memory store of the second device.

34. The apparatus of claim 27, further comprising:

means for storing a representation of the combination of the first and second power requirements in a memory store of the second device.

35. The apparatus of claim 33, further comprising:

means for storing a representation of the combination of the first and second power requirements in a second memory store of the second device.

36. An apparatus for managing an inline power relationship between a first device, a second device and a third device in a wired data telecommunications network, the first device configured as power sourcing equipment (PSE), the second device having a first power requirement and configured as a powered device (PD) and coupled via at least a first pair of conductors to the first device, and the third device having a second power requirement and coupled via at least a second pair of conductors to the second device, the apparatus comprising:

means for determining the second power requirement;

means for calculating a representation of a combination of the first and second power requirements; and

means for communicating a representation of the combination to the first device.

37. The apparatus of claim 36, further comprising:

means for storing a representation of the magnitude of the second power requirement in a first memory store of the second device.

38. The apparatus of claim 36, further comprising:

means for storing a representation of the combination of the first and second power requirements in a memory store of the second device.

39. The apparatus of claim 37, further comprising:

means for storing a representation of the combination of the first and second power requirements in a second memory store of the second device.

40. An apparatus for providing inline power from a first device to a second device and a third device in a wired data telecommunications network, the apparatus comprising:

means for coupling the first device and the second device with a first pair of conductors and a second pair of conductors;

means for tapping power from the first pair of conductors and the second pair of conductors to provide power to couple to the third device; and

means for interrupting power flow from the first and second pairs of conductors to the second device in response to current draw from the second device dropping below a predetermined threshold.

41. The apparatus of claim 40, further comprising:

means for responding to a discovery signal with an identity network in order to obtain inline power.

42. The apparatus of claim 40, further comprising:

means for providing power flow to said third device in response to a manual input signal.

43. The apparatus of claim 40, further comprising:

means for providing power flow to said third device through a keyed connector.

44. An apparatus for providing inline power from a first device to a second device and a third device in a wired data telecommunications network, the apparatus comprising:

means for coupling the first device and the second device with at least a first pair of conductors;

means for tapping power from the at least first pair of conductors to power a controller; and

means for enabling inline power flow from the at least first pair of conductors to the second device in response to the second device responding to a discovery request from the control with a predetermined identity network.

45. The apparatus of claim 44, further comprising:

means for interrupting inline power flow from the at least first pair of conductors to the second device in response to current draw from the second device dropping below a predetermined threshold.

46. An adapter for receiving data and inline power from a first connector adapted to be coupled to a port in a wired data telecommunications network and providing data and inline power to a second connector and power to a third connector, the adapter comprising:

a first coupling means for coupling the adapter to a power sourcing equipment (PSE) device of a wired data telecommunications network having at least two pairs of conductors;

a second coupling means for coupling the adapter to a second device;

a third coupling means for coupling the adapter to a third device;

a first means for tapping power from the first of the at least two pairs of conductors for receiving a first direct current (DC) voltage;

a second means for tapping power from the second of the at least two pairs of conductors for receiving a second DC voltage;

the difference between the first voltage and the second voltage being a difference voltage;

means for applying the difference voltage to an output circuit including the third coupling means.

47. The adapter of claim 46, wherein:

the output circuit includes means for converting the difference voltage to another DC voltage.

48. The adapter of claim 46, wherein:

the output circuit contains only the third coupling means and conductors coupling the third coupling means to the means for applying.

49. The adapter of claim 46, wherein:

the adapter includes means for controlling whether or not power is available at the third coupling means.

50. The adapter of claim 46, further comprising:

manually controllable means for causing the controller to apply power to the third connector.

51. A system for managing an inline power relationship between a first device, a second device and a third device in a wired data telecommunications network, the first device configured as power sourcing equipment (PSE), the second device having a first power requirement and configured as a powered device (PD) and coupled via at least a first pair of conductors to the first device, and the third device having a second power requirement and coupled via at least a second pair of conductors to the second device, the system comprising:

circuitry for communicating from the third device to the second device a representation of a magnitude of the second power requirement;

circuitry for calculating a representation of a combination of the first and second power requirements; and

circuitry for communicating a representation of the combination to the first device.

52. The system of claim 51, wherein said circuitry for communicating from the third device takes place over the at least a second pair of conductors.

53. The system of claim 51, wherein said circuitry for communicating from the third device takes place over a wireless link.

54. The system of claim 51, wherein said circuitry for calculating takes place at the second device.

55. The system of claim 51, wherein said circuitry for communicating the representation of the combination takes place over the at least a first pair of conductors.

56. The system of claim 51, wherein said circuitry for communicating the representation of the combination takes place over a wireless link.

57. The system of claim 51, further comprising:

circuitry for storing a representation of the magnitude of the second power requirement in a first memory store of the second device.

58. The system of claim 51, further comprising:

circuitry for storing a representation of the combination of the first and second power requirements in a memory store of the second device.

59. The system of claim 57, further comprising:

circuitry for storing a representation of the combination of the first and second power requirements in a second memory store of the second device.

60. A system for managing an inline power relationship between a first device, a second device and a third device in a wired data telecommunications network, the first device configured as power sourcing equipment (PSE), the second device having a first power requirement and configured as a powered device (PD) and coupled via at least a first pair of conductors to the first device, and the third device having a second power requirement and coupled via at least a second pair of conductors to the second device, the system comprising:

circuitry for determining the second power requirement;

circuitry for calculating a representation of a combination of the first and second power requirements; and

circuitry for communicating a representation of the combination to the first device.

61. The system of claim 60, further comprising:

circuitry for storing a representation of the magnitude of the second power requirement in a first memory store of the second device.

62. The system of claim 60, further comprising:

circuitry for storing a representation of the combination of the first and second power requirements of the second device.

63. The system of claim 61, further comprising:

circuitry for storing a representation of the combination of the first and second power requirements of the second device.

64. A system apparatus for providing inline power from a first device to a second device and a third device in a wired data telecommunications network, the system comprising:

circuitry for coupling the first device and the second device with a first pair of conductors and a second pair of conductors;

circuitry for tapping power from the first pair of conductors and the second pair of conductors to provide power to couple to the third device; and

circuitry for interrupting power flow from the first and second pairs of conductors to the second device in response to current draw from the second device dropping below a predetermined threshold.

65. The system of claim 64, further comprising:

circuitry for responding to a discovery signal with an identity network in order to obtain inline power.

66. The system of claim 64, further comprising:

circuitry for providing power flow to said third device in response to a manual input signal.

67. The system of claim 64, further comprising:

circuitry for providing power flow to said third device through a keyed connector.

68. A system for providing inline power from a first device to a second device and a third device in a wired data telecommunications network, the system comprising:

circuitry for coupling the first device and the second device with at least a first pair of conductors;

circuitry for tapping power from the at least first pair of conductors to power a controller; and

circuitry for enabling inline power flow from the at least first pair of conductors to the second device in response to the second device responding to a discovery request from the control with a predetermined identity network.

69. The system of claim 68, further comprising:

circuitry for interrupting inline power flow from the at least first pair of conductors to the second device in response to current draw from the second device dropping below a predetermined threshold.

70. A system for receiving data and inline power from a first connector adapted to be coupled to a port in a wired data telecommunications network and providing data and inline power to a second connector and power to a third connector, the system comprising:

a first connector for coupling the powered device (PD) to a power sourcing equipment (PSE) device of a wired data telecommunications network having at least two pairs of conductors;

a second connector for coupling the PD to a second device;

a third connector for coupling the PD to a third device;

a first circuit for tapping power from the first of the at least two pairs of conductors for receiving a first direct current (DC) voltage;

a second circuit for tapping power from the second of the at least two pairs of conductors for receiving a second DC voltage;

the difference between the first voltage and the second voltage being a difference voltage;

circuitry for applying the difference voltage to an output circuit including the third connector.

71. The system of claim 70, wherein:

the output circuit includes circuitry for converting the difference voltage to another DC voltage.

72. The system of claim 70, wherein:

the output circuit contains only the third connector and conductors coupling the third connector to the circuitry for applying.

73. The system of claim 70, wherein:

the system includes circuitry for controlling whether or not power is available at the third connector.

74. The system of claim 70, further comprising:

a manually controllable circuit for causing the circuitry for applying to apply power to the third connector.

75. An adapter for receiving inline power from a first connector adapted to be coupled to a port in a wired data telecommunications network and providing inline power to a second connector and power to a third connector, the adapter comprising:

a first connector for coupling the adapter to a power sourcing equipment (PSE) device of a wired data telecommunications network having at least two pairs of conductors;

a second connector for coupling the adapter to a second device;

a third connector for coupling the adapter to a third device;

a first power tap coupled to receive a first direct current (DC) voltage from a first of the at least two pairs of conductors;

a second power tap coupled to receive a second DC voltage from a second of the at least two pairs of conductors;

the difference between the first voltage and the second voltage being a difference voltage; and

an output circuit including the third connector and adapted to receive the first voltage and the second voltage and provide power to the third connector.

76. The adapter of claim 75, wherein:

the output circuit includes a DC-DC converter for converting the difference voltage to another DC voltage.

77. The adapter of claim 75, wherein:

the output circuit contains only the third connector and conductors coupling the third connector to the controller.

78. The adapter of claim 75, wherein:

the output circuit includes a switch controlled by the controller and controlling whether or not power is available at the third connector.

79. The adapter of claim 75, further comprising:

a control in communication with the output circuit, activation of the control causing the output circuit to apply power to the third connector.

80. The adapter of claim 75, further comprising:

switches in line with each of the conductors of the at least two pairs of conductors, a state of the switches controlled by the output circuit so that the switches are closed if a device is coupled to the second connector and no power is being directed to the third connector.

81. The adapter of claim 75, further comprising:

switches in line with each of the conductors of the at least two pairs of conductors, a state of the switches controlled by the output circuit so that the switches are open if power is being delivered to the third connector and no powered device has been identified as coupled to the second connector.

82. An adapter for receiving inline power from a first connector adapted to be coupled to a port in a wired data telecommunications network and providing data and inline power to a second connector and power to a third connector, the adapter comprising:

a first coupler adapted to couple the adapter to a power sourcing equipment (PSE) device of a wired data telecommunications network having at least two pairs of conductors;

a second coupler adapted to couple the adapter to a second device;

a third coupler adapted to couple the adapter to a third device;

a first power tap adapted to receive a first direct current (DC) voltage from the first of the at least two pairs of conductors;

a second power tap adapted to receive a second DC voltage from the second of the at least two pairs of conductors;

the difference between the first voltage and the second voltage being a difference voltage; and

an output circuit including the third coupler and adapted to receive the first voltage and the second voltage and provide power to the third connector.

83. The adapter of claim 82, wherein:

the output circuit includes a converter adapted to convert the difference voltage to another DC voltage.

84. The adapter of claim 82, wherein:

the adapter includes a circuit adapted to control whether or not power is available at the third coupler.

85. The adapter of claim 82, further comprising:

a manually controllable control for causing the adapter to apply power to the third connector.

86. A method for managing an inline power relationship between a first device, a second device and a third device in a wired data telecommunications network, the first device configured as power sourcing equipment (PSE), the second device having a first power requirement and configured as a powered device (PD) and coupled via at least a first pair of conductors to the first device, and the third device having a second power requirement and coupled via the least a first pair of conductors to the second device, the method comprising:

powering the second device with inline power;

subsequently coupling the third device to the at least a first pair of conductors;

using an active identity network at the third device to communicate the second power requirement to the first device;

allocating at said first device the inline power necessary to meet said second power requirement;

communicating from said first device to said third device a confirmation of inline power allocation; and

responsive to said confirmation, presenting a load at said third device to the at least a pair of conductors.

87. The method of claim 86 wherein said third device also includes a passive identity network.

89. The method of claim 86 wherein said third device also includes a passive identity network.

88. An apparatus for managing an inline power relationship between a first device, a second device and a third device in a wired data telecommunications network, the first device configured as power sourcing equipment (PSE), the second device having a first power requirement and configured as a powered device (PD) and coupled via at least a first pair of conductors to the first device, and the third device having a second power requirement and coupled via the least a first pair of conductors to the second device, the apparatus comprising:

means for powering the second device with inline power;

means for subsequently coupling the third device to the at least a first pair of conductors;

means for using an active identity network at the third device to communicate the second power requirement to the first device;

means for allocating at said first device the inline power necessary to meet said second power requirement;

means for communicating from said first device to said third device a confirmation of inline power allocation; and

means responsive to said confirmation for presenting a load at said third device to the at least a pair of conductors.