Optical data throughput protection switch

• US 6,798,934 B2
• Filed: 12/06/2001
• Issued: 09/28/2004
• Est. Priority Date: 12/06/2001
• Status: Expired due to Fees

• Current Assignee: RPX Clearinghouse LLC (RPX Corporation)
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Patel, Bhupendra, Brown, David W., Parry, Simon P.
• Primary Examiner(s): Ullah, Akm Enayet
• Assistant Examiner(s): Rahll, Jerry T
• Application Number:
  US10/003,252
• Publication Number:
  US 20030108271A1
• Time in Patent Office: 1,027 Days
• Field of Search: 385/16-23, 385/44-45
• US Class Current: 385/16
• CPC Class Codes: G02B 6/355 1x2 switch, i.e. one input and a selectable single output of two possible outputs
• CPC Class Codes: G02B 6/3552 1x1 switch, e.g. on/off switch
• CPC Class Codes: G02B 6/356 in an optical cross-connect device, e.g. routing and switching aspects of interconnecting different paths propagating different wavelengths to (re)configure the various input and output links switching polarized beams G02B6/3594; power equalizers G02B6/356 and G02B6/3594; path selecting means H04Q11/0001
• CPC Class Codes: H04Q 11/0062 Network aspects
• CPC Class Codes: H04Q 2011/0083 Testing; Monitoring

Abstract

An optical data throughput protection switch is provided which provides access to a data-carrying first optical path in a manner which protects the data from interference from equipment utilizing said access, and eliminates optical connectors along the first optical path. The protection switch includes a controlling means and a controllable switch which is optically coupled to the first optical path the termination of a second optical path. The controllable switch is controlled by the controlling means and functions to enable and disable optical coupling between the termination, of the second optical path and the first optical path. This may be effected in a manner that allows access to the first optical path when there is no data traffic thereon, and denies access thereto when data is present, resulting in data throughput on the first optical path being protected from signals of the second optical path.

Claims

1. An optical switch comprising:

a controllable switch, and

a controlling means,

wherein said controllable switch is optically coupled to a first optical path and optically coupled to a termination of a second optical path, said controllable switch at all times providing an unbroken optical pathway along the first optical path, and controlled by the controlling means to enable and disable optical coupling between the termination of the second optical path and the first optical path.

2. The optical switch of claim 1 wherein the controllable switch enables said optical coupling of the termination of the second optical path to the first optical path by causing substantially complete transmission of optical signals of the second optical path to the first optical path, and disables said optical coupling of the termination of the second optical path to the first optical path by causing substantially complete attenuation of optical signals of the second optical path to the first optical path.

3. The optical switch of claim 1 wherein the controlling means controls the controllable switch using a software state variable which is externally modifiable.

4. The optical switch of claim 1 wherein the controlling means receives as input, traffic information of said first optical path, the controlling means controlling the controllable switch using said traffic information, and using a software state variable which is externally modifiable.

5. The optical switch of claim 1 wherein the controlling means comprises a traffic detection means, a software state variable which is externally modifiable, a logic means and a controller, the controlling means receiving as input, traffic information of said first optical path, the controlling means using said traffic information, and the software state variable to control the controllable switch.

6. The optical switch of claim 1 wherein the controllable switch is optically coupled to the first optical path by high optical power compatible connecting means.

7. The optical switch of claim 6 wherein the high optical power compatible connecting means are physical splices.

8. The optical switch of claim 1 wherein the controlling means receives as input, traffic information of said first optical path, for use in controlling the controllable switch.

9. The optical switch of claim 8 wherein the controlling means has a first mode of operation wherein the controlling means:

enables optical coupling between the termination of the second optical path and the first optical path when said traffic information indicates there is no data traffic on the first optical path; and

disables optical coupling between the termination of the second optical path and the first optical path when said traffic information indicates there is data traffic on the first optical path,

whereby data signals of the first optical path are controllably protected from signals from the second optical path.

10. The optical data protection switch of claim 9 wherein the controlling means has a second mode of operation wherein the controlling means controls the controllable switch using a software state variable which is externally modifiable.

11. The optical switch of claim 10 wherein the controlling means comprises a traffic detection means, a software state variable which is externally modifiable, a logic means and a controller, the controlling means receiving as input, traffic information of said first optical path, the controlling means using said traffic information, and the software state variable to control the controllable switch.

12. The optical switch of claim 9 wherein the controllable switch is optically coupled to the first optical path by high optical power compatible connecting means.

13. The optical switch of claim 12 wherein the high optical power compatible connecting means are physical splices.

14. The optical switch of claim 9 wherein the controllable switch enables said optical coupling of the termination of the second optical path to the first optical path by causing substantially complete transmission of optical signals of the second optical path to the first optical path, and disables said optical coupling of the termination of the second optical path to the first optical path by causing substantially complete attenuation of optical signals of the second optical path to the first optical path.

15. An optical switch comprising:

a controllable switch, and

a controlling means,

wherein said controllable switch is optically coupled to a first optical path and optically coupled to a termination of a second optical path, said controllable switch controlled by the controlling means to enable and disable optical coupling between the termination of the second optical path and the first optical path, and wherein the controllable switch further comprises;

a wavelength selective filter,

a controllable optical signal blocker,

a third optical path,

wherein the controllable optical signal blocker is optically coupled to said termination of the second optical path and is controlled by said controlling means to allow and block signals from the second optical path to the third optical path, the third optical path optically coupled to the controllable optical signal blocker and a second input of the wavelength selective filter, the wavelength selective filter optically coupled to the first optical path by a first input and a single output.

16. The optical switch of claim 15 wherein the controllable optical signal blocker operates to allow signals from the second optical path to the third optical path by causing substantially complete transmission of optical signals of the second optical path to the third optical path, and operates to block signals from the second optical path to the third optical path by causing substantially complete attenuation of optical signals of the second optical path to the third optical path.

17. The optical switch of claim 15 wherein the controllable optical signal blocker is an optical shutter.

18. The optical switch of claim 15 wherein the controllable optical signal blocker is a variable optical attenuator.

19. The optical switch of claim 18 wherein the second optical path is optically coupled to an Optical Time Domain Reflectometer, and wherein the wavelength selective filter is substantially transmissive along the first optical path between the first input and the second output of the wavelength selective filter to optical signals in a set of bandwidths corresponding to wavelengths of the carrier signals of the data throughput, the wavelength selective filter routing optical signals of wavelengths corresponding to a pulse from the Optical Time Domain Reflectometer between the second input of the wavelength selective filter and one of:

the second input of the wavelength selective filter; and

the single output of the wavelength selective filter.

20. An optical switch comprising:

a controllable switch, and

a controlling means,

wherein said controllable switch is optically coupled to a first optical path and optically coupled to a termination of a second optical path, said controllable switch controlled by the controlling means to enable and disable optical coupling between the termination of the second optical path and the first optical path, and wherein the second optical path is optically coupled to optical test equipment.

21. The optical switch of claim 20 wherein the optical test equipment is an Optical Time Domain Reflectometer.

22. An optical switch comprising:

a controllable switch, and

a controlling means,

wherein said controllable switch is optically coupled to a first optical path and optically coupled to a termination of a second optical path, said controllable switch controlled by the controlling means to enable and disable optical coupling between the termination of the second optical path and the first optical path, wherein the controlling means receives as input, traffic information of said first optical path, for use in controlling the controllable switch, wherein the controllable switch comprises;

a wavelength selective filter,

a controllable optical signal blocker,

a third optical path,

wherein the controllable optical signal blocker is optically coupled to said termination of the second optical path and is controlled by said controlling means to allow and block signals from the second optical path to the third optical path, the third optical path optically coupled to the controllable optical signal blocker and a second input of the wavelength selective filter, and the wavelength selective filter optically coupled to the first optical path by a first input and a single output.

23. The optical switch of claim 22 wherein the controllable optical signal blocker operates to allow signals from the second optical path to the third optical path by causing substantially complete transmission of optical signals of the second optical path to the third optical path, and operates to block signals from the second optical path to the third optical path by causing substantially complete attenuation of optical signals of the second optical path to the third optical path.

24. The optical switch of claim 22 wherein the controllable optical signal blocker is an optical shutter.

25. The optical switch of claim 22 wherein the controllable optical signal blocker is a variable optical attenuator.

28. The optical switch of claim 25 wherein the second optical path is optically coupled to an Optical Time Domain Reflectometer, and wherein the wavelength selective filter is substantially transmissive along the first optical path between the first input and the second output of the wavelength selective filter to optical signals in a set of bandwidths corresponding to the wavelengths of the carrier signals of the data throughput, the wavelength selective filter routing optical signals of wavelengths corresponding to a pulse from an Optical Time Domain Reflectometer between the second input of the wavelength selective filter and one of:

the second input of the wavelength selective filter; and

the single output of the wavelength selective filter.

26. An optical switch comprising:

a controllable switch, and

wherein said controllable switch is optically coupled to a first optical path and optically coupled to a termination of a second optical path, said controllable switch controlled by the controlling means to enable and disable optical coupling between the termination of the second optical path and the first optical path, wherein the controlling means receives as input, traffic information of said first optical path, for use in controlling the controllable switch, wherein the second optical path is optically coupled to optical test equipment.

27. The optical switch of claim 26 wherein the optical test equipment is an Optical Time Domain Reflectometer.

29. An optical switch comprising:

a controllable switch having a first input coupled to a first optical path and an output connected to the first optical path and a second input coupled to a termination of a second optical path, the controllable switch including a controllable device having a control input; and

a controlling device having an input and an output connected to the control input of the controllable device, wherein said controllable switch at all times provides an unbroken optical pathway along the first optical path and wherein the controllable device under control of the controlling device enables and disables optical coupling between the termination of the second optical path and the first optical path depending upon a signal applied to the input of the controlling device.

30. An optical switch comprising:

a controllable switch, and

a controlling device having an input and an output,

wherein said controllable switch is optically coupled to a first optical path and optically coupled to a termination of a second optical path, said controllable switch controlled by the controlling device to enable and disable optical coupling between the termination of the second optical path and the first optical path, and wherein the controllable switch further comprises;

a wavelength selective filter,

a controllable optical signal blocker having a signal input and a control input,

a third optical path,

wherein the signal input of the controllable optical signal blocker is optically coupled to said termination of the second optical path and the control input of the controllable optical signal blocker is connected to the output of the controlling device wherein the controllable signal blocker is controlled by said controlling device to allow and block signals from the second optical path to the third optical path, the third optical path optically coupled to the controllable optical signal blocker and a second input of the wavelength selective filter, the wavelength selective filter optically coupled to the first optical path by a first input and a single output.

31. An optical switch comprising:

a controllable switch having a first input coupled to a first optical path and an output connected to the first optical path and a second input coupled to a termination of a second optical path, the controllable switch including a controllable device having a control input; and

a controlling device having an input and an output connected to the control input of the controllable device, wherein the controllable device under control of the controlling device enables and disables optical coupling between the termination of the second optical path and the first optical path depending upon a signal applied to the input of the controlling device and wherein the second optical path is optically coupled to test equipment.

32. An optical switch comprising:

a controllable switch, and

a controlling device having an input and an output,

wherein said controllable switch is optically coupled to a first optical path and optically coupled to a termination of a second optical path, said controllable switch controlled by the controlling device to enable and disable optical coupling between the termination of the second optical path and the first optical path, wherein the controlling device receives at its input, traffic information of said first optical path, for use in controlling the controllable switch, and wherein the controllable switch further comprises;

a wavelength selective filter,

a controllable optical signal blocker having a signal input and a control input,

a third optical path,

wherein the signal input of the controllable optical signal blocker is optically coupled to said termination of the second optical path and the control input of the controllable signal blocker is connected to the output of the controlling device wherein the controllable signal blocker is controlled by said controlling device to allow and block signals from the second optical path to the third optical path, the third optical path optically coupled to the controllable optical signal blocker and a second input of the wavelength selective filter, the wavelength selective filter optically coupled to the first optical path by a first input and a single output.

33. An optical switch comprising:

a controllable switch having a first input coupled to a first optical path and an output connected to the first optical path and a second input coupled to a termination of a second optical path, the controllable switch including a controllable device having a control input; and

a controlling device having an input and an output connected to the control input of the controllable device, wherein the controllable device under control of the controlling device enables and disables optical coupling between the termination of the second optical path and the first optical path depending upon a signal applied to the input of the controlling device, the signal being traffic information of said first optical path and wherein the second optical path is optically coupled to test equipment.