Method and apparatus for signaling between an optical cross-connect switch and attached network equipment

• US 6,792,174 B1
• Filed: 11/01/2000
• Issued: 09/14/2004
• Est. Priority Date: 11/02/1999
• Status: Expired due to Fees

• Current Assignee: RPX Clearinghouse LLC (RPX Corporation)
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Ramaswami, Rajiv
• Primary Examiner(s): Chowdhury, Tarifur R.
• Assistant Examiner(s): Wang, George Y.
• Application Number:
  US09/704,445
• Time in Patent Office: 1,413 Days
• Field of Search: 385/16, 385/17, 385/18, 385/24, 385/31, 385/39, 359/127, 359/128, 359/114, 359/115, 359/124, 370/228
• US Class Current: 385/17
• CPC Class Codes: G02B 6/43 Arrangements comprising a plurality of opto-electronic elements and associated optical interconnections
• CPC Class Codes: H04J 14/0293 Optical channel protection
• CPC Class Codes: H04J 14/0295 Shared protection at the optical channel (1:1, n:m)
• CPC Class Codes: H04J 14/0297 Optical equipment protection
• CPC Class Codes: H04Q 11/0062 Network aspects
• CPC Class Codes: H04Q 11/0066 Provisions for optical burst or packet networks
• CPC Class Codes: H04Q 2011/0024 using space switching
• CPC Class Codes: H04Q 2011/0026 using free space propagation (e.g. lenses, mirrors)
• CPC Class Codes: H04Q 2011/0041 Optical control
• CPC Class Codes: H04Q 2011/0043 Fault tolerance
• CPC Class Codes: H04Q 2011/005 Arbitration and scheduling
• CPC Class Codes: H04Q 2011/0073 Provisions for forwarding or routing, e.g. lookup tables
• CPC Class Codes: H04Q 2011/0081 Fault tolerance; Redundancy; Recovery; Reconfigurability
• CPC Class Codes: H04Q 2011/0083 Testing; Monitoring
• CPC Class Codes: H04Q 2011/0088 Signalling aspects

Abstract

Methods, apparatus and systems for signaling information between an optical cross-connect switch and attached network equipment such as Internet Protocol (IP) routers, WDM terminals, SONET add/drop multiplexers and ATM switches. In one embodiment, an out-of-band signaling interface between an optical cross-connect switch and attached network equipment is realized by using an out-of-band communication channel over a network. In another embodiment, a decentralized signaling interface is provided by one or more dedicated signal lines between an optical cross-connect switch and attached network equipment.

Claims

1. A signaling interface comprising:

an optical cross-connect switch to couple to network equipment over a network, the optical cross-connect switch to receive network management signals from the network equipment and to transmit network management signals to the network equipment, the optical cross-connect switch including

an optical switch fabric of optical switches to switch optical data signals from one optical network connection to another optical network connection; and

,

a signaling channel on the network to transceive network management signals, the signaling channel independent of the optical network connections to transceive optical data signals, the signaling channel to carry the network management signals between the optical cross-connect switch and the network equipment.

2. The signaling interface of claim 1 wherein,

the network management signals received from the network equipment by the optical cross-connect switch include information regarding performance of the optical cross-connect switch.

3. The signaling interface of claim 1 wherein,

the network management signals received from the network equipment by the optical cross-connect switch include information to control the optical cross-connect switch.

4. The signaling interface of claim 1 wherein,

the network management signals transmitted to the network equipment by the optical cross-connect switch include information regarding performance of the optical cross-connect switch.

5. The signaling interface of claim 1 wherein,

the network management signals transmitted to the network equipment by the optical cross-connect switch include information regarding the optical data signals input into the optical cross-connect switch.

6. The signaling interface of claim 1 wherein,

the signaling channel is an out-of-band signaling channel.

7. The signaling interface of claim 1 wherein,

the optical cross-connect switch further includes

one or more port cards, each of the one or more port cards coupled to the optical switch fabric to accept optical data signals and having an optical output port to couple to the network equipment and transport optical data signals thereto.

8. The signaling interface of claim 7 wherein,

the network equipment has one or more optical-electrical-optical converters each providing an electrical signal responsive to optical data signals received from the optical cross-connect switch.

9. The signaling interface of claim 8 wherein,

the network management signals transmitted from the network equipment over the signaling channel to the optical cross-connect switch are responsive to the optical data signals received from the optical cross-connect switch.

10. The signaling interface of claim 1 wherein,

the optical cross-connect switch further includes

a network management controller to couple to the network to transmit and to receive network management signals over the signaling channel regarding the optical cross-connect switch and the network equipment.

11. The signaling interface of claim 1 wherein,

the optical switch fabric includes a pair of optical switch matrices each having a plurality of micro-machined mirrors to direct optical data signals from the one optical network connection to the another optical network connection.

12. The signaling interface of claim 11 wherein,

the optical cross-connect switch further includes

a bounce mirror between the pair of optical switch matrices.

13. The signaling interface of claim 1 wherein,

the network is one or more of a local area network, a metropolitan network, a wide area network, an internet, or an intranet.

14. The signaling interface of claim 1 wherein,

the optical cross-connect switch couples to the network using an Ethernet connection or an RS232 connection.

18. The method of claim 14 wherein,

the switching of the input optical signals into attached network equipment is provide by micro-machined mirrors.

15. A method for signaling an optical cross-connect switch, the method comprising:

providing a network management signaling channel on a network independent of the optical network connections carrying data;

switching input optical signals into attached network equipment; and

receiving a network management signal over the network management signaling channel from attached network equipment in response to the switching of the input optical signals.

16. The method of claim 15 further comprising:

transmitting a network management signal over the network management signaling channel to attached network equipment in response to the switching of the input optical signals.

17. The method of claim 15 wherein,

the network management signaling channel is an out-of-band signaling channel.

19. A signaling interface comprising:

one or more port cards in an optical cross-connect switch, each of the one or more port cards to accept optical data signals and having an optical output port to couple to network equipment and transport the optical data signals thereto, and

each of the one or more port cards further having a dedicated switch management signal line, in addition to the optical output port, to couple to a respective port card of the network equipment, the dedicated switch management signal line to transmit and receive switch management signals regarding the optical cross-connect switch and the network equipment.

20. The signaling interface of claim 19 wherein,

the switch management signals received from network equipment over the dedicated signal line include information regarding performance of the optical cross-connect switch.

21. The signaling interface of claim 19 wherein,

the switch management signals received from network equipment over the dedicated signal line include information to control the optical cross-connect switch.

22. The signaling interface of claim 19 wherein,

the network equipment has one or more optical-electrical-optical converters each providing an electrical signal responsive to optical data signals received from the one or more port cards.

23. The signaling interface of claim 22 wherein,

the switch management signals received from the network equipment over the dedicated switch management signal line are responsive to electrical signals converted from optical data signals received from the one or more port cards by the one or more optical-electrical-optical converters.

24. The signaling interface of claim 19 wherein,

the optical cross-connect switch includes a pair of optical switch matrices each having a plurality of micro-machined mirrors to direct optical data signals from one network connection to another.

25. The signaling interface of claim 24 wherein,

the optical cross-connect switch further includes

a bounce mirror between the pair of optical switch matrices.

26. The signaling interface of claim 19 wherein,

the dedicated switch management signal line is an optical connection.

27. The signaling interface of claim 26 wherein,

each of the one or more port cards further includes an optical-electrical converter to couple to the dedicated switch management signal line, the optical-electrical converter to convert optical switch management signals on the dedicated switch management signal line into electrical switch management signals.

28. The signaling interface of claim 19 wherein,

the dedicated switch management signal line is an electrical connection.

29. The signaling interface of claim 19 wherein,

the signals transmitted to network equipment over the dedicated switch management signal line from the one or more port cards includes information regarding performance of the optical cross-connect switch.

30. The signaling interface of claim 19 wherein,

the switch management signals transmitted to network equipment over the dedicated switch management signal line from the one or more port cards includes information regarding the optical data signals input into the optical cross-connect switch.

31. A method for signaling an optical cross-connect switch, the method comprising:

providing a dedicated switch management signal line, independent of optical data ports for optical data signals, between I/O ports of the optical cross-connect switch and I/O ports of attached network equipment;

switching optical data signals into the attached network equipment; and

receiving a first control signal over the dedicated switch management signal line from the attached network equipment in response to the switching of the optical data signals.

32. The method of claim 31 further comprising:

transmitting a second control signal over the dedicated switch management signal line to an I/O port of the attached network equipment in response to the switching of the optical data signals.

33. The method of claim 31 wherein,

the receiving of the first control signal over the dedicated switch management signal line is received by an I/O port of the optical cross-connect switch.

34. The method of claim 31 wherein,

the switching of input optical data signals into attached network equipment is provided by micro-machined mirrors.

35. A method of network restoration in an optical telecommunications network, the method comprising:

coupling network equipment to an optical cross-connect switch;

detecting a network failure in the optical telecommunications network by the network equipment;

signaling the network failure to the optical cross-connect switch using a network management signaling interface, the network management signaling interface independent of I/O ports, the I/O ports for optical data signals; and

responsive to the signaling, the optical cross-connect switch adjusting to the network failure in order to restore the optical telecommunications network.

36. The method of claim 35 wherein,

the network equipment includes optical-electrical-optical converters to detect the network failure and the optical cross-connect is without optical-electrical-optical converters to detect the network failure.

37. The method of claim 35 wherein,

the network failure is a signal failure.

38. The method of claim 35 wherein,

the network failure is a signal degradation.

39. The method of claim 35 wherein,

the adjusting to the network failure includes switching from a failed data line to an unused operational data line.

40. A method of forming a connection in a telecommunications network, the method comprising:

signaling a request for the connection to an optical cross-connect switch using a network management signaling interface, the network management signaling interface independent of I/O ports, the I/O ports for optical data signals;

setting up the connection through the optical cross-connect switch; and

signaling the availability of the connection through the optical cross-connect switch using the network management signaling interface.

41. The method of claim 40 wherein,

the connection through the optical cross-connect switch is an optical path to transport the optical data signals.

42. The method of claim 40 wherein,

the network management signaling interface is an out-of-band signaling interface.

43. The method of claim 42 wherein,

the out-of-band signaling interface is a network connection.

44. The method of claim 40 wherein,

the network management signaling interface is an in-band signaling interface.

45. The method of claim 44 wherein,

the in-band signaling interface is a direct signal connection between the optical cross-connect switch and the network equipment requesting the connection.

46. A method of adjusting parameters in network equipment of a telecommunications network, the method comprising:

signaling a request to adjust parameters in an optical network equipment using a network management signaling interface, the network management signaling interface independent of I/O ports, the I/O ports for optical data signals;

adjusting the optical network equipment in response to the request to adjust parameters in the optical network equipment; and

signaling the completion of the adjustment to the optical network equipment using the network management signaling interface.

47. The method of claim 46 wherein,

the connection through the optical network equipment is an optical cross-connect switch.

48. The method of claim 46 wherein,

the network management signaling interface is an out-of-band signaling interface.

49. The method of claim 48 wherein,

the out-of-band signaling interface is a network connection.

50. The method of claim 46 wherein,

the network management signaling interface is an in-band signaling interface.

51. The method of claim 50 wherein,

the in-band signaling interface is a direct signal connection between the optical cross-connect switch and the network equipment requesting the connection.

52. A signaling interface comprising:

an optical cross-connect switch to couple to network equipment over a network, the optical cross-connect switch to receive network management signals from the network equipment and to transmit network management signals to the network equipment, the optical cross-connect switch including

an optical switch fabric of optical switches to switch optical data signals from one optical network connection to another optical network connection; and

,

an out-of-band signaling channel on the network independent of the optical switch fabric, the out-of-band signaling channel to carry the network management signals between the optical cross-connect switch and the network equipment.

53. The signaling interface of claim 52 wherein,

the network management signals received from the network equipment by the optical cross-connect switch include information regarding performance of the optical cross-connect switch.

54. The signaling interface of claim 52 wherein,

the network management signals received from the network equipment by the optical cross-connect switch include information to control the optical cross-connect switch.

55. The signaling interface of claim 52 wherein,

the network management signals transmitted to the network equipment by the optical cross-connect switch include information regarding performance of the optical cross-connect switch or information regarding the optical signals input into the optical cross-connect switch.

56. The signaling interface of claim 52 wherein,

the optical cross-connect switch further includes

one or more port cards, each of the one or more port cards coupled to the optical switch fabric to accept optical data signals and having an optical output port to couple to the network equipment and transport optical signals thereto.

57. The signaling interface of claim 56 wherein,

the network equipment has one or more optical-electrical-optical converters each providing an electrical signal responsive to optical data signals received from the optical cross-connect switch.

58. The signaling interface of claim 57 wherein,

the network management signals transmitted from the network equipment over the out-of-band signaling channel to the optical cross-connect switch are responsive to the optical data signals received from the optical cross-connect switch.

59. The signaling interface of claim 52 wherein,

the optical cross-connect switch further includes

a network management controller to couple to the network to transmit and to receive the network management signals over the out-of-band signaling channel regarding the optical cross-connect switch and the network equipment.

60. The signaling interface of claim 52 wherein,

the optical switch fabric includes a pair of optical switch matrices each having a plurality of micro-machined mirrors to direct optical data signals from the one optical network connection to the another optical network connection.

61. The signaling interface of claim 60 wherein,

the optical cross-connect switch further includes

a bounce mirror between the pair of optical switch matrices.

62. The signaling interface of claim 52 wherein,

the network is one or more of a local area network, a metropolitan network, a wide area network, an internet, or an intranet.

63. The signaling interface of claim 52 wherein,

the optical cross-connect switch couples to the network equipment to provide the out-of-band signaling channel using an Ethernet connection or an RS232 connection.