Multi-station physical layer communication over TP cable

• US 20060117089A1
• Filed: 06/15/2005
• Published: 06/01/2006
• Est. Priority Date: 11/30/2004
• 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 7,724,650 B2
• Time in Patent Office: Days
• US Class Current: 709/208
• CPC Class Codes: H04L 1/22 using redundant apparatus to increase reliability
• CPC Class Codes: H04L 12/10 Current supply arrangements
• CPC Class Codes: H04L 41/0668 by dynamic selection of recovery network elements, e.g. replacement by the most appropriate element after failure
• CPC Class Codes: H04L 67/125 involving control of end-device applications over a network
• CPC Class Codes: H04L 69/24 Negotiation of communication capabilities
• CPC Class Codes: H04L 69/40 for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection management of faults, events, alarms or notifications in data switching networks H04L41/06

Abstract

Wired data telecommunications networks can make advantageous use of a communications capability between and among more than two network devices. Such capabilities may be utilized in providing redundancy of data and/or inline power capabilities from a pair of network devices to a third network device receiving the redundant capability. Impedance modulated communications are provided in a wired data telecommunications network among at least a first, second and third network device coupled together via a Y device. The Y device couples the three network devices (higher order Y devices could couple more than three devices) allowing monitoring of communications and inline power provision so that one of the network devices may act in response to monitored conditions by communicating via impedance modulated communications with one or both of the other network devices.

Claims

1. A method for providing data telecommunications and/or inline power between a first and a second network device associated with a first node of a network and a third network device associated with a second node of the network, in a wired data telecommunications network, the method comprising:

directing simultaneously, from the first network device, network communications to the third network device and to the second network device at a first speed through a Y-device;

directing simultaneously, from the third network device, network communications to the first network device and to the second network device at the first speed through the Y-device;

monitoring network communications between the first network device and the third network device with the second network device; and

detecting at the second network device a condition in the network communications between the first network device and the third network device.

2. The method of claim 1, further comprising:

initiating, responsive to said detecting, an impedance modulated signal from the second network device onto the wired data telecommunications network;

receiving at the first network device, the impedance modulated signal; and

backing off communications between the first network device and the third network device in response to said receiving.

3. The method of claim 2, further comprising:

attempting to establish communications between the first network device and the third network device at a second speed different from said first speed.

4. The method of claim 3, wherein:

said second speed is lower than said first speed.

5. The method of claim 3, further comprising:

failing to establish communications between the first network device and the third network device at a second different from said first speed;

establishing a replacement communications connection between the second network device and the third network device in response to said failing.

6. The method of claim 5, wherein:

said establishing establishes the connection at a second speed different from said first speed.

7. The method of claim 6, wherein:

said second speed is lower than said first speed.

8. The method of claim 7, further comprising:

sending a message to a network control point in response to said detecting.

9. The method of claim 8, wherein said sending is performed using the wired data telecommunications network to send a message from the second network device.

10. The method of claim 8, wherein said sending is performed using a wireless telecommunications link to send a message from the second network device to a wireless node coupled to the wired data telecommunications network, and from the wireless node to the network control point.

11. An apparatus for providing data telecommunications and/or inline power between a first and a second network device associated with a first node of a network and a third network device associated with a second node of the network, in a wired data telecommunications network, the apparatus comprising:

means for directing simultaneously, from the first network device, network communications to the third network device and to the second network device at a first speed through a Y-device;

means for directing simultaneously, from the third network device, network communications to the first network device and to the second network device at the first speed through the Y-device;

means for monitoring network communications between the first network device and the third network device with the second network device; and

means for detecting at the second network device a condition in the network communications between the first network device and the third network device.

12. A network device providing wired data telecommunications network communications between a first network node and a second network node in a wired data telecommunications network, the device comprising:

a first element for directing, from the first network node, wired data telecommunications network communications to and from the second node;

a second element for monitoring wired data telecommunications network communications between the first element and the second node; and

a Y device having a first, second and third port with at least two pairs of conductors coupled across the first, second and third ports, the first port of the Y device coupled to the first element, the second port of the Y device coupled to the second node, and the third port of the Y device coupled to the second element.

13. The device of claim 12, wherein the first port of the Y device is coupled with wiring to the first element.

14. The device of claim 12, wherein the second port of the Y device is coupled with wiring to the second node.

15. The device of claim 12, wherein the third port of the Y device is coupled with wiring to the second element.

16. The device of claim 12, further comprising:

a router for directing, from the first network node, wired data telecommunications network communications to and from the first element and the second element.

17. The device of claim 12, wherein the wired data telecommunications network communications include data and inline power.

18. The device of claim 12, further comprising:

a detector associated with the second element, the detector detecting a condition in the wired data telecommunications network communications between the first element and the second node; and

an impedance communications circuit initiating impedance modulated communications from the second element through the Y device to the first element in response to the detected condition.

19. The device of claim 18, wherein the wired data telecommunications network communications include data and inline power.

20. The device of claim 16, wherein the wired data telecommunications network communications include data and inline power.

21. The device of claim 16, further comprising:

a detector associated with the second element, the detector detecting a condition in the wired data telecommunications network communications between the first element and the second node; and

an impedance communications circuit initiating impedance modulated communications from the second element through the Y device to the first element in response to the detected condition.

22. The device of claim 21, wherein the wired data telecommunications network communications include data and inline power.

23. A network device providing communications and/or inline power between a first network node and a second network node in a wired data telecommunications network, the device comprising:

a first element for directing, from the first network node, wired data telecommunications network communications to and from the second network node;

a second element for monitoring wired data telecommunications network communications between the first element and the second node; and

a Y device having a first, second and third port with at least two pairs of conductors coupled across the first, second and third ports,

wherein the first port of the Y device is coupled to the first element, the second port of the Y device is coupled to the second network node, and the third port of the Y device is coupled to the second element.

24. The device of claim 23, further comprising:

a third element for directing, from the first network node, wired data telecommunications network communications to and from the first element and the second element.

25. The device of claim 24, wherein the wired data telecommunications network communications include data and inline power.

26. The device of claim 25, further comprising:

a detector associated with the second element, the detector detecting a condition in the wired data telecommunications network communications between the first element and the second network node via the Y device; and

an impedance communications module initiating impedance modulated communications from the second element through the Y device to the first element in response to the detected condition.

27. A system for providing data telecommunications and/or inline power between a first and a second network device associated with a first node of a network and a third network device associated with a second node of the network, in a wired data telecommunications network, the system comprising:

circuitry for directing simultaneously, from the first network device, network communications to the third network device and to the second network device at a first speed through a Y-device;

circuitry for directing simultaneously, from the third network device, network communications to the first network device and to the second network device at the first speed through the Y-device;

circuitry for monitoring network communications between the first network device and the third network device, said circuitry for monitoring associated with the second network device; and

circuitry for detecting at the second network device a condition in the network communications between the first network device and the third network device.

28. The system of claim 27, further comprising:

circuitry for transmitting, responsive to said circuitry for detecting, an impedance modulated signal from the second network device onto the wired data telecommunications network;

circuitry for receiving at the first network device, the impedance modulated signal; and

circuitry responsive to said circuitry for receiving for backing off communications between the first network device and the third network device.

29. A network device providing communications and/or inline power between a first network node and a second network node in a wired data telecommunications network, the device comprising:

a router for directing, from the first network node, wired data telecommunications network communications to and from a first wired data telecommunications network device (first network device) and a second wired data telecommunications network device (second network device);

a first port of a Y device coupled to the second network node, the Y device having at least three ports with at least two pairs of conductors coupled across the at least three ports;

a second port of the Y device coupled to a first port of the first network device;

a third port of the Y device coupled to a first port of the second network device;

a monitor associated with the second network device monitoring communications and/or inline power between the first port of the first network device and the second network node;

a detector coupled to the monitor, the detector detecting a condition in the communications and/or inline power between the first port of the first network device and the second network node; and

an impedance communications module initiating impedance modulated communications from the second network device through the Y device to the first network device in response to the detected condition.

30. The device of claim 29, wherein the impedance communications module includes:

a switch having at least a first state and a second state, wherein

the wiring coupling the third port of the Y device to the first port of the second network device is terminated with a first impedance when said switch is in said first state; and

the wiring coupling the third port of the Y device to the first port of the second network device is terminated with a second impedance when said switch is in said second state.

31. The device of claim 30, wherein the impedance modulated communications include a message requesting the first port of the first network device to back off.

32. The device of claim 31, wherein the impedance modulated communications include a message requesting the first port of the first network device to attempt to reestablish communications with the second network node at a lower speed than was originally established.

33. A method for providing inline power between a first and a second network device associated with a first node of a network and a third network device associated with a second node of the network, in a wired data telecommunications network, the method comprising:

providing first inline power at a first voltage level from the first network device to the third network device;

providing second inline power at a second voltage level from the second network device to the third network device; and

selecting one of the first inline power and the second inline power at the third network device in response to the voltage level associated therewith.

34. A method for providing inline power between a first and a second network device associated with a first node of a network and a third network device associated with a second node of the network, in a wired data telecommunications network, the method comprising:

providing inline power at a first voltage level from the first network device to the third network device;

coupling the inline power from the first network device to the second network device thorough a Y-device;

monitoring the first network device at the second network device; and

detecting at the second network device a condition of the first network device.

35. The method of claim 34, further comprising:

initiating, responsive to said detecting, an impedance modulated signal from the second network device onto the wired data telecommunications network;

receiving at the first network device, the impedance modulated signal; and

backing off inline power provided between the first network device and the third network device in response to said receiving.

36. The method of claim 35, further comprising:

supplying inline power at a second voltage level from the second network device to the third network device.

37. The method of claim 36, wherein:

said second voltage level is lower than said first voltage level.

38. A method for providing inline power between a first and a second network device associated with a first node of a network and a third network device associated with a second node of the network, in a wired data telecommunications network, the method comprising:

providing first inline power at a first voltage level from the first network device to the third network device;

providing second inline power at a second voltage level from the second network device to the third network device; and

selecting one of the first inline power and the second inline power at the third network device in response to the voltage level associated therewith.

39. A method for providing inline power between a first and a second network device associated with a first node of a network and a third network device associated with a second node of the network, in a wired data telecommunications network, the method comprising:

providing inline power at a first voltage level from the first network device to the third network device;

coupling the inline power from the first network device to the second network device thorough a Y-device;

monitoring the first network device at the second network device; and

detecting at the second network device a condition of the first network device.

40. The method of claim 39, further comprising:

initiating, responsive to said detecting, an impedance modulated signal from the second network device onto the wired data telecommunications network;

receiving at the first network device, the impedance modulated signal; and

backing off inline power provided between the first network device and the third network device in response to said receiving.

41. The method of claim 40, further comprising:

supplying inline power at a second voltage level from the second network device to the third network device.

42. The method of claim 41, wherein:

said second voltage level is lower than said first voltage level.