High power classification for power over Ethernet

• US 20050197094A1
• Filed: 02/10/2005
• Published: 09/08/2005
• Est. Priority Date: 10/16/2003
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Microsemi Corp. - Analog Mixed Signal Group, Ltd. (Microchip Technology Incorporated)
• Inventors: Darshan, Yair, Ferentz, Alon
• Granted Patent: US 7,460,889 B2
• Time in Patent Office: Days
• US Class Current: 455/402
• CPC Class Codes: H04L 12/10 Current supply arrangements
• CPC Class Codes: H04L 69/24 Negotiation of communication capabilities

Abstract

A method for determining the classification of a powered device, the method comprising: obtaining a first classification over a first power path; obtaining a second classification over a second power path; comparing the obtained first classification with the obtained second classification; and in the event the obtained first classification is different from the obtained second classification determining a combined classification as a decoded value of the obtained first classification and the obtained second classification.

Claims

1. A local area network adapted to supply power to at least one powered device over a plurality of communication cabling paths, the local area network comprising:

a powered device;

power sourcing equipment; and

communication cabling comprising a plurality of twisted wire pairs connecting said power sourcing equipment to said powered device, said communication cabling providing a first power path comprising a first set of twisted wire pairs of said communication cabling and a second power path comprising a second set of twisted wire pairs of said communication cabling;

said power sourcing equipment comprising;

a control circuit;

a first power source responsive to said control circuit adapted to supply a first power to said powered device via said first power path; and

a second power source responsive to said control circuit adapted to supply a second power to said powered device via said second power path,

said control circuit being operative to obtain a first classification of said powered device via said first power path and a second classification of said powered device via said second power path and in the event that said obtained first classification does not equal said obtained second classification to identity said powered device as a powered device capable of receiving power over a combination of said first power path and said second power path.

2. A local area network according to claim 1 wherein said control circuit is further operative to determine a combined classification for said powered device, said combined classification being a decoded result of said obtained first classification and said obtained second classification.

3. A local area network according to claim 2, wherein in the event that said obtained first classification equals said obtained second classification said control circuit is operative to provide power over only one of said first power path and said second power path.

4. A local area network according to claim 1, wherein in the event that said obtained first classification equals said obtained second classification said control circuit is operative to provide power over only one of said first power path and said second power path.

5. Power sourcing equipment providing power via a plurality of ports for connection over communication cabling to a single powered device, the power sourcing equipment comprising:

a first power source operable to provide power via a first port;

a second power source operable to provide power via a second port;

a control circuit;

said control circuit being operative to obtain a first classification of a connected powered device via said first port and a second classification of the connected powered device via said second port and in the event that said obtained first classification does not equal said obtained second classification to identity the connected powered device as a powered device capable of receiving power over a combination of said first port and said second port.

6. Power sourcing equipment according to claim 5, wherein said control circuit is further operative to determine a combined classification for the powered device said combined classification being a decoded result of said obtained first classification and said obtained second classification.

7. Power sourcing equipment according to claim 6, wherein in the event that said obtained first classification equals said obtained second classification said control circuit is operative to provide power via only one of said first port and said second port.

8. Power sourcing equipment according to claim 8, wherein in the event that said first classification equals said second classification said control circuit is operative to provide power via only one of said first port and said second port.

9. A method for determining the classification of a powered device, the method comprising:

obtaining a first classification over a first power path;

obtaining a second classification over a second power path;

comparing said obtained first classification with said obtained second classification; and

in the event said obtained first classification is different from said obtained second classification determining a combined classification as a decoded value of said obtained first classification and said obtained second classification.

10. A method according to claim 9, further comprising in the event said obtained first classification is different from said obtained second classification, supplying power over said first path and said second path.

11. A method according to claim 10, further comprising in the event said obtained first classification is not different from said obtained second classification, supplying power over only one of said first path and said second path.

12. A method according to claim 9, further comprising in the event said obtained first classification is not different from said obtained second classification, supplying power over only one of said first path and said second path.

13. A method according to claim 9, further comprising in the event said obtained first classification is not different from said obtained second classification, supplying power over only one of said first path and said second path in accordance with said obtained classification.

14. A local area network adapted to supply power to at least one powered device over a plurality of communication cabling paths, the local area network comprising:

a powered device;

power sourcing equipment; and

communication cabling comprising a plurality of twisted wire pairs connecting said power sourcing equipment to said powered device, said communication cabling providing a first power path comprising a first set of twisted wire pairs of said communication cabling and a second power path comprising a second set of twisted wire pairs of said communication cabling;

said power sourcing equipment comprising;

a control circuit;

a first power source responsive to said control circuit adapted to supply a first power to said powered device via said first power path; and

a second power source responsive to said control circuit adapted to supply a second power to said powered device via said second power path,

said control circuit being operative to obtain a first classification of said powered device via said first power path and a second classification of said powered device via said second power path and to classify said powered device as a result of said obtained first classification and second classification.

15. Power sourcing equipment providing power via a plurality of ports for connection over communication cabling to a single powered device, the power sourcing equipment comprising:

a first power source operable to provide power via a first port;

a second power source operable to provide power via a second port;

a control circuit;

said control circuit being operative to obtain a first classification of a connected powered device via said first port and a second classification of the connected powered device via said second port and to determine the classification as a result of said obtained first classification and said obtained second classification.

16. Power sourcing equipment according to claim 15, wherein said control circuit is further operative to determine a combined classification for the powered device said combined classification being a decoded result of said first classification and said second classification.

17. Power sourcing equipment according to claim 16, wherein in the event that at least one of said first obtained classification and said obtained second classification is indicative of a high power powered device, said control circuit is operative to provide power via both said first port and said second port.

18. Power sourcing equipment according to claim 15, wherein said control circuit is further operative to simultaneously detect a powered device along said first and second ports.

19. A method for determining the classification of a powered device, the method comprising:

detecting a first signature impedance along a first power path;

detecting a second signature impedance along a second power path;

in the event that said detected first signature impedance and said second signature impedance are both indicative of a valid connected device to be powered, detecting a third signature impedance simultaneously along said first and said second power paths;

in the event that said detected third signature impedance is indicative of a valid connected device to be powered, obtaining a first classification over said first power path and obtaining a second classification over a second power path; and

powering both said first path and said second path in accordance with said obtained first and second classifications.

20. A method according to claim 19, wherein in the event that said detected third signature impedance is indicative of a valid connected device to be powered, the method further comprises:

in the event that one of said obtained first classification and said obtained second classification is indicative of high powering, determining a combined classification as a decoded value of said obtained first classification and said obtained second classification.