Private network link verification procedure in free space optical communication network

• US 7,924,700 B2
• Filed: 06/01/2006
• Issued: 04/12/2011
• Est. Priority Date: 10/05/2000
• Status: Expired due to Term

• Current Assignee: ThinkLogix, LLC (Ascend Innovation Management, LLC)
• Original Assignee: Kiribati Wireless Ventures LLC (Intellectual Ventures LLC)
• Inventors: Shivnan, Aine
• Primary Examiner(s): NGUYEN, HANH N
• Application Number:
  US11/445,996
• Publication Number:
  US 20060233548A1
• Time in Patent Office: 1,776 Days
• Field of Search: 370/469, 370/244, 370/254, 370/216, 370/218, 370/225, 370/227, 370/228, 370/241, 370/395.2, 370/419, 370/420, 370/410, 709/249, 709/237, 709/239, 709/224, 709/227, 709/228, 709/220, 709/221, 709/222
• US Class Current: 370/216
• CPC Class Codes: H04B 10/1149 Arrangements for indoor wireless networking of information
• CPC Class Codes: H04Q 11/0062 Network aspects
• CPC Class Codes: H04Q 2011/0083 Testing; Monitoring
• CPC Class Codes: H04Q 2011/0086 Network resource allocation, dimensioning or optimisation
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements

Abstract

A system and method for verifying the integrity of a communication link in a wireless optical communication network. The system and method include monitoring the communication link on at least two levels and enabling or disabling signaling over the communication link appropriately depending on events reported through the system.

Claims

1. A method, comprising:

a first network device monitoring a physical level of a communication link between the first network device and a second network device;

the first network device monitoring a second level of the communication link, wherein said monitoring of the second level is usable to detect content errors in data received over the physical level of the communication link; and

the first network device enabling transmission of data over the communication link in response to determining that failures in the physical level of the communication link are below a first threshold and failures in the second level of the communication link are below a second threshold.

2. The method of claim 1,

wherein said monitoring the physical level includes monitoring data received optically;

and

wherein said determining that failures in the second level of the communication link are below the second threshold includes determining that the data received over the physical level of the communication link is received from the second network device.

3. The method of claim 1,

wherein said monitoring the physical level includes monitoring data received via radio frequency;

and

wherein said determining that failures in the second level of the communication link are below the second threshold includes determining that a handshake attempt over said physical level of said communication link is successful.

4. The method of claim 1,

wherein said monitoring the physical level includes monitoring data received via microwave;

and

wherein said determining that failures in the second level of the communication link are below the second threshold includes determining that a handshake attempt over said physical level of said communication link is accomplished within a threshold number of attempts.

5. The method of claim 1, wherein said monitoring the physical level includes monitoring data received via a synchronous optical network.

6. The method of claim 5, wherein said monitoring data received via the synchronous optical network includes detecting changes in a section, line, or path of the synchronous optical network.

7. The method of claim 1, wherein said monitoring the physical level includes monitoring data received via asynchronous transport mode.

8. The method of claim 7, wherein said monitoring the data received via the asynchronous transport mode includes detecting loss-of-cell delineation.

9. The method of claim 1, wherein said monitoring the physical level further includes monitoring a data switch.

10. The method of claim 1, wherein said monitoring the physical level includes monitoring data received via an Ethernet protocol.

11. The method of claim 10, wherein said monitoring the physical level includes monitoring an Internet Protocol stack.

12. The method of claim 10, wherein said monitoring the physical level includes monitoring an Internet protocol-based transport mechanism.

13. The method of claim 12, wherein the Internet protocol-based transport mechanism is TCP/IP.

14. The method of claim 1, wherein said monitoring the physical layer includes monitoring data received via an Internet protocol-based transport mechanism.

15. The method of claim 14, wherein the Internet protocol-based transport mechanism is TCP/IP.

16. The method of claim 1, wherein said monitoring the second level includes monitoring an optical device configured to receive data from a second optical device, and wherein monitoring the optical device includes detecting a data content error by determining the said optical device has received data from a device other than the second optical device.

17. The method of claim 16, wherein the optical device and the second optical device are each optical transceivers.

18. The method of claim 1, wherein said monitoring the second level includes monitoring a first optical device configured to transmit data to a second optical device, and wherein said monitoring the first optical device includes detecting a data content error by determining that the second optical device has received data originally transmitted by the first optical device.

19. The method of claim 1, wherein said determining that failures in the physical level of the communication link are below the first threshold includes determining a number of fluctuations in a status of the physical level.

20. The method of claim 19, wherein said determining that failures in the physical level of the communication link are below the first threshold further includes comparing the determined number of fluctuations to a configurable threshold.

21. The method of claim 1, wherein said determining that failures in the physical level of the communication link are below the first threshold includes determining that a failure detected in the physical level does not exist for longer than a first amount of time.

22. The method of claim 21, wherein determining that failures in the second level of the communication link are below the second threshold includes determining that a failure detected in the second level does not exist for longer than a second amount of time.

23. The method of claim 22, wherein the first amount of time and the second amount of time are different.

24. The method of claim 23, wherein the first amount of time the said second amount of time are configurable.

25. The method of claim 1, wherein determining that failures in the second level of the communication link are below the second threshold includes determining that a failure detected in the second level does not exist for longer than a first amount of time.

26. The method of claim 1, wherein said determining that failures in the physical level of the communication link are below the first threshold includes detecting that a failure in the physical level does not occur more than a first number of times.

27. The method of claim 26, wherein the first number of times is configurable.

28. The method of claim 1, wherein determining that failures in the second level of the communication link are below the second threshold includes detecting that a failure in the second level does not occur more than a first number of times.

29. The method of claim 28, wherein the first number of times is configurable.

30. The method of claim 1, further comprising:

monitoring one or more additional communication links, wherein said monitoring the one or more additional communication links includes monitoring a physical level and a second level of each of said one or more additional communication links, wherein said monitoring of the second level of a given one of said one or more additional communication links is usable to detect content errors in data received over the given link; and

enabling transmission of data over those additional communication links that are determined to have failures in the physical level of the given link below a first additional threshold and failures in the second level of the given link below a second additional threshold.

31. The method of claim 30, wherein the communication link and the one or more additional communication links include two or more optical devices.

32. The method of claim 30, wherein the communication link and the one or more additional communication links include two or more freespace optical devices.

33. The method of claim 30, wherein the communication link and the one or more additional communication links include two or more freespace optical transceivers.

34. The method of claim 1, wherein said monitoring of the physical level includes monitoring a plurality of physical devices.

35. The method of claim 34, wherein the plurality of physical devices includes an optical device.

36. The method of claim 34, wherein the plurality of physical devices includes an optical transceiver.

37. The method of claim 34, wherein the plurality of physical devices includes a freespace optical transceiver.

38. The method of claim 34, further comprising:

detecting a failure by one of the plurality of physical devices; and

determining which of the plurality of physical devices generated the failure.

39. The method of claim 1, wherein said monitoring of the physical level includes monitoring a freespace optical device and a second device configured to operate as a backup to said freespace optical device.

40. The method of claim 39, wherein the second device is a radio frequency device.

41. The method of claim 40, wherein the second device is a microwave device.

42. An apparatus, comprising:

a first interface coupled to a first communication link, the first communication link having a physical level and a second level, wherein the first communication link is between the apparatus and a network device; and

a processor configured to monitor the physical level and the second level of the first communication link between the apparatus and the network device, wherein said monitoring of the second level is usable to detect content errors in data received over said physical level of said first communication link;

wherein the processor is configured to enable transmission of data over the first communication link between the apparatus and the network device based at least in part on determining, using the results of said monitoring the physical level and said second level, that the first communication link is operational by;

detecting that failures in the physical level are below a first threshold; and

detecting that failures in the second level are below a second threshold.

43. The apparatus of claim 42, wherein the processor is configured to enable transmission of data over the first communication link in response to the processor determining that the first communication link is operational.

44. The apparatus of claim 43,

wherein the physical level includes an optical device;

and

wherein the processor detecting that failures in the second level are below the second threshold includes the processor determining that a handshake attempt over the physical level of said communication link is successful.

45. The apparatus of claim 43, wherein the physical level includes an optical transceiver.

46. The apparatus of claim 45, wherein the optical transceiver is a freespace optical transceiver.

47. The apparatus of claim 43, wherein the physical level includes a microwave device.

48. The apparatus of claim 43,

wherein the physical level includes a radio frequency device;

and

wherein the processor detecting that failures in the second level are below the second threshold includes the processor determining that the data received over the physical level of the first communication link is received from the network device.

49. The apparatus of claim 43, wherein the physical level is configured to transmit data according to an Ethernet protocol.

50. The apparatus of claim 43, wherein the physical level is configured to transmit data according to an Internet protocol-based data transport mechanism.

51. The apparatus of claim 43, wherein the processor is configured to detect a content error in data received over the first communication link in response to receiving data from a device other than said network device.

52. The apparatus of claim 43, wherein the processor is configured to detect a content error in data received over the first communication link in response to receiving data originally transmitted by the apparatus.

53. The apparatus of claim 52, wherein the physical level includes an optical transceiver, and wherein the processor is configured to detect a content error in data received over the first communication link in response to the optical transceiver receiving data transmitted by the apparatus.

54. The apparatus of claim 43, wherein the physical level includes a plurality of physical devices.

55. The apparatus of claim 54, wherein the plurality of physical devices includes a first device and a backup device to the first device.

56. The apparatus of claim 55, wherein the first device is an optical device, and wherein the first threshold is configurable.

57. The apparatus of claim 56, wherein the first device is a freespace optical device, and wherein the second threshold is configurable.

58. The apparatus of claim 42, further comprising one or more additional interfaces, each of which is coupled to a respective additional communication link, wherein each additional communication link includes a physical level and a second level, wherein monitoring of the second level of a given additional communication link is usable to detect a content error in data received over the given link.

59. The apparatus of claim 58, wherein the first communication link and the additional communication links respectively include two or more optical communication links.

60. An apparatus, comprising:

an interface to a communication link, wherein the communication link includes a physical level and a second level, wherein the communication link is between the apparatus and network device, wherein monitoring of the second level is usable to detect content errors in data received via said communication link;

a first means for monitoring a status of the physical level of the communication link;

a second means for monitoring a status of the second level of the communication link;

a third means for enabling transmission of data via the communication link in response to determining, based at least in part on the monitoring of the status of the physical level and the monitoring of the status of the second level, that the communication link is operational,

wherein the third means determining that the first communication link is operational includes;

detecting that failures in the physical level are below a first threshold; and

detecting that failures in the second level are below a second threshold.

61. A method for monitoring a status of a communication link, said method comprising:

a first network device monitoring a physical level of the communication link, wherein the communication link is between the first network device and a second network device;

the first network device monitoring a second level of the communication link, wherein said monitoring of the second level is usable to detect content errors of data received over the physical level of the communication link;

the first network device determining whether the communication link is operational, wherein determining that the communication link is operational includes;

detecting that failures in the physical level of the communication link are below a first configurable threshold; and

detecting that failures in the second level of the communication link are below a second configurable threshold, wherein the second configurable threshold and the first configurable threshold are set to different values; and

the first network device disabling transmission of data over the communication link in response to determining that the communication link is not operational.

62. The method of claim 61, wherein the physical level includes an optical device.

63. The method of claim 61,

wherein said monitoring of the second level of the communication link includes monitoring an optical device configured to receive data from a second optical device;

and

wherein detected failures in the second level of the communication link include a determination that the optical device has received data from a device other than the second optical device.

64. The method of claim 61, further comprising setting the first configurable threshold to a received value.

65. The method of claim 64, wherein the received value is a time threshold, and wherein said detecting that the failures in the physical level are below the first configurable threshold includes determining that failures exists over a time period exceeding the time threshold specified by said received value.

66. The method of claim 61, wherein said detecting that failures in the physical level are below the first configurable threshold includes detecting loss-of-cell delineation.

67. A method for monitoring a communication link comprising:

a first network device monitoring a physical level of the communication link, wherein the communication link is between the first network device and a second network device, and wherein said monitoring the physical level is usable to detect data transport errors over the communication link;

the first network device monitoring a second level of the communication link, wherein said monitoring the second level is usable to detect content errors of data received over the physical level of said communication link; and

the first network device enabling transmission of data over said communication link based at least in part on determining that the detected data transport errors are below a first threshold, and that the detected content errors are below a second threshold;

wherein said communication link uses an Internet-protocol data transport mechanism.

68. The method of claim 67, wherein the Internet-protocol data transport mechanism includes TCP/IP, wherein the first threshold is configurable, and wherein the second threshold is configurable and is distinct from the first threshold.

69. A method comprising:

a first network device determining that a physical level of a communication link between the first network device and a second network device has become operational;

in response to said determining that the physical level is operational, the first network device determining that a second level of the communication link between the first network device and the second network device is operational based at least in part on detecting that content errors in data received over the communication link are below a first threshold value;

in response to said determining that the second level is operational, the first network device determining whether said physical level is stable based at least in part on detecting that transport errors over the communication link are below a second threshold value; and

in response to determining that said physical level is stable, the first network device enabling transmission of data over said communication link.