Optical layer survivability and security system using optical label switching and high-speed optical header reinsertion

• US 6,160,651 A
• Filed: 12/29/1999
• Issued: 12/12/2000
• Est. Priority Date: 01/25/1999
• Status: Expired due to Term

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Telcordia Technologies Incorporated (Telefonaktiebolaget LM Ericsson)
• Inventors: Chang, Gee-Kung, Ellinas, Georgios, Graveman, Richard, Monma, Clyde
• Primary Examiner(s): NEGASH, KINFE MICHAEL
• Application Number:
  US09/473,431
• Time in Patent Office: 349 Days
• Field of Search: 359/123-124, 359/135, 359/125, 370/352, 370/392, 370/471, 370/355-356
• US Class Current: 398/79
• CPC Class Codes: H04J 14/0227 Operation, administration, maintenance or provisioning [OAMP] of WDM networks, e.g. media access, routing or wavelength allocation
• CPC Class Codes: H04J 14/0241 Wavelength allocation for communications one-to-one, e.g. unicasting wavelengths
• CPC Class Codes: H04J 14/0278 WDM optical network architectures
• CPC Class Codes: H04J 14/0283 WDM ring architectures
• CPC Class Codes: H04J 14/0284 WDM mesh architectures
• CPC Class Codes: H04J 14/0293 Optical channel protection
• CPC Class Codes: H04J 14/0294 Dedicated protection at the optical channel (1+1)
• CPC Class Codes: H04J 14/0295 Shared protection at the optical channel (1:1, n:m)
• CPC Class Codes: H04J 14/0298 with sub-carrier multiplexing [SCM]
• CPC Class Codes: H04Q 11/0062 Network aspects
• CPC Class Codes: H04Q 2011/0016 using wavelength multiplexing or demultiplexing
• 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 2011/0088 Signalling aspects

Abstract

An optical signaling header technique applicable to optical networks wherein packet routing information is embedded in the same channel or wavelength as the data payload so that both the header and data payload propagate through network elements with the same path and the associated delays. The technique effects survivability and security of the optical networks by encompassing conventional electronic security with an optical security layer by generating replicated versions of the input data payload at the input node, and the transmission of each of the replicated versions over a corresponding one of the plurality of links. Moreover, each of the links is composed of multiple wavelengths to propagate optical signals or optical packets, and each of the replicated versions of the data payload may be propagated over a selected one of the wavelengths in each corresponding one of the plurality of links.

Claims

1. A method for propagating an input data payload from an input network element to an output network element in a wavelength division multiplexing (WDM) network composed of a plurality of network elements, each including a switch, the input network element having a plurality of links coupled to the network, the input data payload having a given format and protocol, the method comprising the steps of

generating and storing a local routing look-up table in each of the network elements, each local routing table determining alternative local routes through the associated one of the network elements,

generating and storing replicated versions of the input data payload in the input network element,

adding an optical header to each of the replicated versions of the input data payload to produce a plurality of corresponding optical signals, the header having a format and protocol and being indicative of the local route through each of the network elements for each of the optical signals, the format and protocol of the data payload being independent of the format and protocol of the header,

optically transmitting each of the optical signals over a corresponding one of the links connected to the input element,

detecting the header of each of the optical signals at the network elements to produce a corresponding switch control signal as each of the optical signals propagates through the WDM network,

selecting one of the local routes for routing each of the optical signals through each of the network elements by looking up the switch control signal in the corresponding local routing table to operate the corresponding switch, and

routing each of the optical signals to the output network element through the network elements in correspondence to the selected route,

wherein each header is composed of one or more header signals each being conveyed by a distinct sub-carrier frequency and arranged so that the highest detectable sub-carrier frequency corresponds to an active header signal, the plurality of sub-carrier frequencies occupying a frequency band above the input data payload,

the step of detecting including the steps of

concurrently measuring the header signals to produce a header selection signal,

selecting the active header signal as conveyed by the highest detectable sub-carrier frequency under control of the header selection signal, and

processing the active header signal to obtain the switch control signal for routing the corresponding one of the optical signals,

the method further comprising, prior to the step of routing, the steps of

determining a new active header signal, and

inserting into said corresponding one of the optical signals the new active header signal as conveyed by a next highest sub-carrier frequency exceeding the highest detectable sub-carrier frequency.

2. A method for propagating an input data payload from an input network element to an output network element in a wavelength division multiplexing (WDM) network composed of a plurality of network elements, each including a switch, the input network element having a plurality of links coupled to the network, the input data payload having a given format and protocol, the method comprising the steps of

generating and storing a local routing look-up table in each of the network elements, each local routing table determining alternative local routes through the associated one of the network elements,

generating and storing replicated versions of the input data payload in the input network element,

adding an optical header to each of the replicated versions of the input data payload to produce a plurality of corresponding optical signals, the header having a format and protocol and being indicative of the local route through each of the network elements for each of the optical signals, the format and protocol of the data payload being independent of the format and protocol of the header,

optically transmitting each of the optical signals over a corresponding one of the links connected to the input element,

detecting the header of each of the optical signals at the network elements to produce a corresponding switch control signal as each of the optical signals propagates through the WDM network,

selecting one of the local routes for routing each of the optical signals through each of the network elements by looking up the switch control signal in the corresponding local routing table to operate the corresponding switch, and

routing each of the optical signals to the output network element through the network elements in correspondence to the selected route,

wherein the header is composed of one or more header signals each being conveyed by a distinct sub-carrier frequency and arranged so that the highest detectable sub-carrier frequency corresponds to an active header signal, the plurality of sub-carrier frequencies occupying a frequency band above the data payload,

the step of detecting including the steps of

concurrently measuring the header signals conveyed by the header to produce a header selection signal,

selecting the active header signal as conveyed by the highest detectable sub-carrier frequency under control of the header selection signal, and

processing the optical signal to delete the header signals and recover only the data payload,

the method further comprising, prior to the step of routing, the steps of

determining a new active header signal, and

inserting into the optical signal the new active header signal in place of the deleted header signals.

3. A method for propagating an input data payload from an input network element to an output network element in a wavelength division multiplexing (WDM) network composed of a plurality of network elements, each including a switch, the input network element having a plurality of links coupled to the network, the input data payload having a given format and protocol, the method comprising the steps of

generating and storing a local routing look-up table in each of the network elements, each local routing table determining alternative local routes through the associated one of the network elements,

generating and storing replicated versions of the input data payload in the input network element,

adding an optical header to each of the replicated versions of the input data payload to produce a plurality of corresponding optical signals, the header having a format and protocol and being indicative of the local route through each of the network elements for each of the optical signals, the format and protocol of the data payload being independent of the format and protocol of the header,

optically transmitting each of the optical signals over a corresponding one of the links connected to the input element,

detecting the header of each of the optical signals at the network elements to produce a corresponding switch control signal as each of the optical signals propagates through the WDM network,

selecting one of the local routes for routing each of the optical signals through each of the network elements by looking up the switch control signal in the corresponding local routing table to operate the corresponding switch, and

routing each of the optical signals to the output network element through the network elements in correspondence to the selected route,

wherein the header is composed of one or more header signals each being conveyed by a distinct sub-carrier frequency and arranged so that the highest detectable sub-carrier frequency corresponds to an active header signal, the plurality of sub-carrier frequencies occupying a frequency band above the data payload,

the step of detecting including the steps of

concurrently measuring the header signals to produce a header selection signal,

selecting the active header signal as conveyed by the highest detectable sub-carrier frequency under control of the header selection signal, and

processing the active header signal to produce the switch control signal for routing the optical signal,

the method further comprising, prior to the step of routing, the steps of

determining a new active header signal,

optically circulating the light burst to produce a time-extended light burst under control of the preamble,

light modulating the time-extended light burst with the new active header signal conveyed by a next highest sub-carrier frequency exceeding the highest detectable sub-carrier frequency to produce an outgoing optical header, and

inserting the outgoing optical header into the optical signal to augment the optical signal.

4. A method for propagating an input data payload from an input network element to an output network element in a wavelength division multiplexing (WDM) network composed of a plurality of network elements, each including a switch, the input network element having a plurality of links coupled to the network, the input data payload having a given format and protocol, the method comprising the steps of

generating and storing a local routing look-up table in each of the network elements, each local routing table determining alternative local routes through the associated one of the network elements,

generating and storing replicated versions of the input data payload in the input network element,

adding an optical header to each of the replicated versions of the input data payload to produce a plurality of corresponding optical signals, the header having a format and protocol and being indicative of the local route through each of the network elements for each of the optical signals, the format and protocol of the data payload being independent of the format and protocol of the header,

optically transmitting each of the optical signals over a corresponding one of the links connected to the input element,

detecting the header of each of the optical signals at the network elements to produce a corresponding switch control signal as each of the optical signals propagates through the WDM network,

selecting one of the local routes for routing each of the optical signals through each of the network elements by looking up the switch control signal in the corresponding local routing table to operate the corresponding switch, and

routing each of the optical signals to the output network element through the network elements in correspondence to the selected route,

wherein the header is composed of a header signal being conveyed by a distinct carrier frequency such that the spectrum of the header signal occupies a frequency band above the data payload,

the step of detecting including the steps of

opto-electrically converting the optical signal to detect header information in the header signal, and

reading the header information to produce a switch control signal to route the incoming optical signal,

the method further comprising, prior to the step of routing, the steps of

optically processing the optical signal to delete the header signal and recover only the data payload, and

inserting a new header signal into the optical signal in place of the deleted header signal.

5. A method for propagating a sequence of related data payloads from an input network element to an output network element in a wavelength division multiplexing (WDM) network composed of a plurality of network elements, each including a switch, the input network element having a plurality of links coupled to the network, each of the related data payloads having a given format and protocol, the method comprising the steps of

generating and storing a local routing look-up table in each of the network elements, each local routing table determining alternative local routes through the associated one of the network elements,

generating and storing replicated versions of each of the related data payloads in the input network element,

adding an optical header to each of the replicated versions of the input data payloads to produce a plurality of corresponding optical signals, the header having a format and protocol and being indicative of the local route through each of the network elements for each of the optical signals, the format and protocol of the data payload being independent of the format and protocol of the header,

optically transmitting each of the optical signals over a corresponding one of the plurality of links coupled to the input element,

detecting the header of each of the optical signals at the network elements to produce a corresponding switch control signal as each of the optical signals propagates through the WDM network,

selecting one of the local routes for routing each of the optical signals through each of the network elements by looking up the switch control signal in the corresponding local routing table to operate the corresponding switch, and

routing each of the optical signals to the output network element through the network elements in correspondence to the selected route,

wherein each header is composed of one or more header signals each being conveyed by a distinct sub-carrier frequency and arranged so that the highest detectable sub-carrier frequency corresponds to an active header signal, the plurality of sub-carrier frequencies occupying a frequency band above the input data payload,

the step of detecting including the steps of

concurrently measuring the header signals to produce a header selection signal,

selecting the active header signal as conveyed by the highest detectable sub-carrier frequency under control of the header selection signal, and

processing the active header signal to obtain the switch control signal for routing the corresponding one of the optical signals,

the method further comprising, prior to the step of routing, the steps of

determining a new active header signal, and

inserting into said corresponding one of the optical signals the new active header signal as conveyed by a next highest sub-carrier frequency exceeding the highest detectable sub-carrier frequency.

6. The method as recited in claim 5 wherein the optical header includes a label-switch state for routing the corresponding optical signal through the network elements, and the step of adding an optical header includes the steps of determining and inserting in the optical header an appropriate label-switch state for routing the corresponding optical signal from the input network element to the output network element through the network elements.

7. The method as recited in claim 5 wherein each of the links includes multiple optical wavelengths and wherein the step of optically transmitting includes the step of propagating each of the optical signals over a selected one of the wavelengths composing said one of the corresponding links.

8. The method as recited in claim 7 wherein the step of generating includes the step of electronically replicating each of the related data payloads.

9. The method as recited in claim 8 wherein the step of storing includes the step of storing each electronically replicated one of the related data payloads.

10. The method as recited in claim 5 wherein the step of adding the optical header includes the step of assigning the local route for each of the optical signals through the network based upon a time-dependent assignment algorithm.

11. The method as recited in claim 5 wherein the step of generating includes the steps of grouping a plurality of incoming data payloads to produce the related data payloads and partitioning the related data payloads into disjoint subsets, and the step of storing further includes the step of storing the disjoint subsets.

12. The method as recited in claim 11 wherein each of the links includes multiple optical wavelengths and wherein the step of optically transmitting includes the step of propagating each of the subsets over a selected one of the wavelengths composing said one of the corresponding links.

13. The method as recited in claim 12 wherein the step of optically transmitting over one of the corresponding links includes the step of assigning said selected one of the wavelengths based upon a time-dependent assignment algorithm.

14. The method as recited in claim 13 wherein the time-dependent assignment algorithm is based upon generating secure pseudo-random numbers.

15. A method for propagating a sequence of related data payloads from an input network element to an output network element in a wavelength division multiplexing (WDM) network composed of a plurality of network elements, each including a switch, the input network element having a plurality of links coupled to the network, each of the related data payloads having a given format and protocol, the method comprising the steps of

generating and storing a local routing look-up table in each of the network elements, each local routing table determining alternative local routes through the associated one of the network elements,

generating and storing replicated versions of each of the related data payloads in the input network element,

adding an optical header to each of the replicated versions of the input data payloads to produce a plurality of corresponding optical signals, the header having a format and protocol and being indicative of the local route through each of the network elements for each of the optical signals, the format and protocol of the data payload being independent of the format and protocol of the header,

optically transmitting each of the optical signals over a corresponding one of the plurality of links coupled to the input element,

detecting the header of each of the optical signals at the network elements to produce a corresponding switch control signal as each of the optical signals propagates through the WDM network,

selecting one of the local routes for routing each of the optical signals through each of the network elements by looking up the switch control signal in the corresponding local routing table to operate the corresponding switch, and

routing each of the optical signals to the output network element through the network elements in correspondence to the selected route,

wherein the header is composed of one or more header signals each being conveyed by a distinct sub-carrier frequency and arranged so that the highest detectable sub-carrier frequency corresponds to an active header signal, the plurality of sub-carrier frequencies occupying a frequency band above the data payload,

the step of detecting including the steps of

concurrently measuring the header signals conveyed by the header to produce a header selection signal,

selecting the active header signal as conveyed by the highest detectable sub-carrier frequency under control of the header selection signal, and

processing the optical signal to delete the header signals and recover only the data payload,

the method further comprising, prior to the step of routing, the steps of

determining a new active header signal, and

inserting into the optical signal the new active header signal in place of the deleted header signals.

16. The method as recited in claim 15 wherein the optical header includes a label-switch state for routing the corresponding optical signal through the network elements, and the step of adding an optical header includes the steps of determining and inserting in the optical header an appropriate label-switch state for routing the corresponding optical signal from the input network element to the output network element through the network elements.

17. The method as recited in claim 15 wherein each of the links includes multiple optical wavelengths and wherein the step of optically transmitting includes the step of propagating each of the optical signals over a selected one of the wavelengths composing said one of the corresponding links.

18. The method as recited in claim 17 wherein the step of generating includes the step of electronically replicating each of the related data payloads.

19. The method as recited in claim 18 wherein the step of storing includes the step of storing each electronically replicated one of the related data payloads.

20. The method as recited in claim 15 wherein the step of adding the optical header includes the step of assigning the local route for each the optical signals through the network based upon a time-dependent assignment algorithms.

21. The method as recited in claim 15 wherein the step of generating includes the steps of grouping a plurality of incoming data payloads to produce the related data payloads and partitioning the related data payloads into disjoint subsets, and the step of storing further includes the step of storing the disjoint subsets.

22. The method as recited in claim 21 wherein each of the links includes multiple optical wavelengths and wherein the step of optically transmitting includes the step of propagating each of the subsets over a selected one of the wavelengths composing said one of the corresponding links.

23. The method as recited in claim 22 wherein the step of optically transmitting over one of the corresponding links includes the step of assigning said selected one of the wavelengths based upon a time-dependent assignment algorithm.

24. The method as recited in claim 23 wherein the time-dependent assignment algorithm is based upon generating secure pseudo-random numbers.

25. A method for propagating a sequence of related data payloads from an input network element to an output network element in a wavelength division multiplexing (WDM) network composed of a plurality of network elements, each including a switch, the input network element having a plurality of links coupled to the network, each of the related data payloads having a given format and protocol, the method comprising the steps of

generating and storing a local routing look-up table in each of the network elements, each local routing table determining alternative local routes through the associated one of the network elements,

generating and storing replicated versions of each of the related data payloads in the input network element,

adding an optical header to each of the replicated versions of the input data payloads to produce a plurality of corresponding optical signals, the header having a format and protocol and being indicative of the local route through each of the network elements for each of the optical signals, the format and protocol of the data payload being independent of the format and protocol of the header,

optically transmitting each of the optical signals over a corresponding one of the plurality of links coupled to the input element,

detecting the header of each of the optical signals at the network elements to produce a corresponding switch control signal as each of the optical signals propagates through the WDM network,

selecting one of the local routes for routing each of the optical signals through each of the network elements by looking up the switch control signal in the corresponding local routing table to operate the corresponding switch, and

routing each of the optical signals to the output network element through the network elements in correspondence to the selected route,

wherein the header is composed of one or more header signals each being conveyed by a distinct sub-carrier frequency and arranged so that the highest detectable sub-carrier frequency corresponds to an active header signal, the plurality of sub-carrier frequencies occupying a frequency band above the data payload,

the step of detecting including the steps of

concurrently measuring the header signals to produce a header selection signal,

selecting the active header signal as conveyed by the highest detectable sub-carrier frequency under control of the header selection signal, and

processing the active header signal to produce the switch control signal for routing the optical signal,

the method further comprising, prior to the step of routing, the steps of

determining a new active header signal,

optically circulating the light burst to produce a time-extended light burst under control of the preamble,

light modulating the time-extended light burst with the new active header signal conveyed by a next highest sub-carrier frequency exceeding the highest detectable sub-carrier frequency to produce an outgoing optical header, and

inserting the outgoing optical header into the optical signal to augment the optical signal.

26. The method as recited in claim 25 wherein the optical header includes a label-switch state for routing the corresponding optical signal through the network elements, and the step of adding an optical header includes the steps of determining and inserting in the optical header an appropriate label-switch state for routing the corresponding optical signal from the input network element to the output network element through the network elements.

27. The method as recited in claim 25 wherein each of the links includes multiple optical wavelengths and wherein the step of optically transmitting includes the step of propagating each of the optical signals over a selected one of the wavelengths composing said one of the corresponding links.

28. The method as recited in claim 27 wherein the step of generating includes the step of electronically replicating each of the related data payloads.

29. The method as recited in claim 28 wherein the step of storing includes the step of storing each electronically replicated one of the related data payloads.

30. The method as recited in claim 25 wherein the step of adding the optical header includes the step of assigning the local route for each of the optical signals through the network based upon a time-dependent assignment algorithm.

31. The method as recited in claim 25 wherein the step of generating includes the steps of grouping a plurality of incoming data payloads to produce the related data payloads and partitioning the related data payloads into disjoint subsets, and the step of storing further includes the step of storing the disjoint subsets.

32. The method as recited in claim 31 wherein each of the links includes multiple optical wavelengths and wherein the step of optically transmitting includes the step of propagating each of the subsets over a selected one of the wavelengths composing said one of the corresponding links.

33. The method as recited in claim 32 wherein the step of optically transmitting over one of the corresponding links includes the step of assigning said selected one of the wavelengths based upon a time-dependent assignment algorithm.

34. The method as recited in claim 33 wherein the time-dependent assignment algorithm is based upon generating secure pseudo-random numbers.

35. A method for propagating a sequence of related data payloads from an input network element to an output network element in a wavelength division multiplexing (WDM) network composed of a plurality of network elements, each including a switch, the input network element having a plurality of links coupled to the network, each of the related data payloads having a given format and protocol, the method comprising the steps of

generating and storing a local routing look-up table in each of the network elements, each local routing table determining alternative local routes through the associated one of the network elements,

generating and storing replicated versions of each of the related data payloads in the input network element,

adding an optical header to each of the replicated versions of the input data payloads to produce a plurality of corresponding optical signals, the header having a format and protocol and being indicative of the local route through each of the network elements for each of the optical signals, the format and protocol of the data payload being independent of the format and protocol of the header,

optically transmitting each of the optical signals over a corresponding one of the plurality of links coupled to the input element,

detecting the header of each of the optical signals at the network elements to produce a corresponding switch control signal as each of the optical signals propagates through the WDM network,

selecting one of the local routes for routing each of the optical signals through each of the network elements by looking up the switch control signal in the corresponding local routing table to operate the corresponding switch, and

routing each of the optical signals to the output network element through the network elements in correspondence to the selected route,

wherein the header is composed of a header signal being conveyed by a distinct carrier frequency such that the spectrum of the header signal occupies a frequency band above the data payload,

the step of detecting including the steps of

opto-electrically converting the optical signal to detect header information in the header signal, and

reading the header information to produce a switch control signal to route the incoming optical signal,

the method further comprising, prior to the step of routing, the steps of

optically processing the optical signal to delete the header signal and recover only the data payload, and

inserting a new header signal into the optical signal in place of the deleted header signal.

36. The method as recited in claim 35 wherein the optical header includes a label-switch state for routing the corresponding optical signal through the network elements, and the step of adding an optical header includes the steps of determining and inserting in the optical header an appropriate label-switch state for routing the corresponding optical signal from the input network element to the output network element through the network elements.

37. The method as recited in claim 35 wherein each of the links includes multiple optical wavelengths and wherein the step of optically transmitting includes the step of propagating each of the optical signals over a selected one of the wavelengths composing said one of the corresponding links.

38. The method as recited in claim 37 wherein the step of generating includes the step of electronically replicating each of the related data payloads.

39. The method as recited in claim 38 wherein the step of storing includes the step of storing each electronically replicated one of the related data payloads.

40. The method as recited in claim 35 wherein the step of adding the optical header includes the step of assigning the local route for each of the optical signals through the network based upon a time-dependent assignment algorithm.

41. The method as recited in claim 35 wherein the step of generating includes the steps of grouping a plurality of incoming data payloads to produce the related data payloads and partitioning the related data payloads into disjoint subsets, and the step of storing further includes the step of storing the disjoint subsets.

42. The method as recited in claim 41 wherein each of the links includes multiple optical wavelengths and wherein the step of optically transmitting includes the step of propagating each of the subsets over a selected one of the wavelengths composing said one of the corresponding links.

43. The method as recited in claim 42 wherein the step of optically transmitting over one of the corresponding links includes the step of assigning said selected one of the wavelengths based upon a time-dependent assignment algorithm.

44. The method as recited in claim 43 wherein the time-dependent assignment algorithm is based upon generating secure pseudo-random numbers.