Method and apparatus for analyzing events in a telecommunications system

• US 7,304,958 B2
• Filed: 07/10/2002
• Issued: 12/04/2007
• Est. Priority Date: 12/23/1994
• Status: Expired due to Fees

• Current Assignee: Viavi Solutions, Inc. (Lumentum Holdings Inc.)
• Original Assignee: Acterna LLC (Lumentum Holdings Inc.)
• Inventors: Hartmann, Paul R., Tyburski, Edward S., Nelson, Derek J.
• Primary Examiner(s): Phunkulh; Bob A.
• Application Number:
  US10/194,520
• Publication Number:
  US 20030043753A1
• Time in Patent Office: 1,973 Days
• Field of Search: None
• US Class Current: 370/249
• CPC Class Codes: H04J 3/14 Monitoring arrangements for SDH/SONET rings H04J3/085
• CPC Class Codes: H04M 3/10 Providing fault- or trouble-signals
• CPC Class Codes: H04M 3/244 for multiplex systems
• CPC Class Codes: H04M 3/303 and using PCM multiplexers, e.g. pair gain systems
• CPC Class Codes: H04Q 2213/1316 Service observation, testing
• CPC Class Codes: H04Q 2213/13162 Fault indication and localisation
• CPC Class Codes: H04Q 2213/1332 Logic circuits
• CPC Class Codes: H04Q 2213/13322 Integrated circuits
• CPC Class Codes: H04Q 2213/13349 Network management
• CPC Class Codes: H04Q 2213/1336 Synchronisation

Abstract

A method and apparatus for automated sectionalization of a DS1/DS3 data path based upon information received at a single location along the path. A test and monitor device is located at a point of demarcation between an LEC and an IEC. A Remote Module is located at a point of demarcation between the LEC and CPE. The test and monitor device is fully ANSI compatible. The information that is received is processed in a three step process in order to generate a “Sectionalizer Report”. In preparing the Sectionalizer Report, the information output from a filter is used to determine where particular Events originated.

Claims

1. A system for determining the status of a telecommunications circuit, including:

(a) a monitoring device located at a network interface between the telecommunications circuit and a customer installation, generating data derived from the content of signals received by the monitoring device from the circuit and transmitting the generated data; and

(b) a sectionalizer device, coupled by the circuit to the monitoring device, receiving said generated data from the monitoring device, detecting when an Event has occurred, and determining, based upon the generated data, in which portion of the circuit from among multiple circuit portions the Event originated;

wherein signals transmitted over the circuit include both a payload and overhead, and the signals received by the sectionalizer device from the monitoring device indicate both inability to detect a payload and degradation of the signal due to errors in either the payload or the overhead.

2. The system of claim 1, wherein the sectionalizer determines in which of the following portions of the circuit the Event has originated:

a portion of the data path which lies between the customer installation and the monitoring device;

a portion of the data path which lies between the monitoring device and the sectionalizer device;

a portion of the data path which lies between the sectionalizer device and the monitoring device; and

a portion of the data path which lies between the monitoring device and the customer installation.

3. The system of claim 1, wherein the sectionalizer is further for communicating to an Operations System whenever an Event is initially detected or ceases to occur.

4. The system of claim 1, wherein data transmitted by the monitoring device is sent in an overhead channel of the circuit.

5. The system of claim 1, wherein the sectionalizer device includes a filter for time correlating Events detected and reported by more than one device.

6. The system of claim 5, wherein the filter delays the processing of the data received by the sectionalizer device for a predetermined amount of time, the delay beginning at the time a new event is reported.

7. The system of claim 6, wherein Events detected by either the monitoring device or the sectionalizer device are assigned an event level, and the filter delays are terminated if the received data includes an event level which is greater than a subsequently received event level.

8. A system for dividing a data path into a plurality of legs and determining in which of the plurality of legs an Event has originated, including:

(a) a monitoring device capable of monitoring signals on the data path to detect either one or more Events or a signal indicative of an occurrence of one or more Events, the placement of the monitoring device defining a first end of a first, second, third and fourth leg, the second end of the first and second leg being defined by a terminating device; and

(b) sectionalizer device coupled to the monitoring device over the third and fourth leg of the data path adapted to receive signals from the monitoring device indicating in which leg one of the Events originated based upon the received signals, the placement of the sectionalizer device defining the second end of the third and fourth leg;

wherein signals transmitted over the circuit include both a payload and overhead, and the signals received by the sectionalizer device from the monitoring device indicate both inability to detect a payload and degradation of the signal due to errors in either the payload or the overhead.

9. The system of claim 8, wherein the monitoring device transmits a variant of a conventional alarm indication signal in response to detection of conditions which would lead to transmission of an alarm indication signal if detected by the monitoring device on the signal from the data path.

10. The system of claim 9, wherein the sectionalizer determines that one of the Events originated in the first leg if the signal received from the monitoring device comprises the variant of the conventional alarm indication signal.

11. The system of claim 9, wherein the sectionalizer determines that one of the Events originated in the second leg if the signal received from the monitoring device comprises the variant of the conventional remote alarm indication signal.

12. The system of claim 9, wherein the sectionalizer determines that one of the Events originated in the third leg if the signal received from the monitoring device comprises an alarm indication signal which is not a variant of a conventional alarm indication signal.

13. The system of claim 9, wherein the sectionalizer determines that an event originated in the second leg if the signal received from the monitoring device comprises a remote alarm indication signal which is not a variant of a conventional alarm indication signal.

14. A system for generating information regarding the origin of Events in a data path and determining the origin of the Events based upon the generated information, including:

(a) at least one monitoring device capable of monitoring signals on the data path to detect either the Events or a signal indicative of an occurrence of one of the Events; and

(b) a sectionalizer device coupled to the at least one monitoring device for receiving data indicating which of the at least one monitoring devices has detected either one of the Events or a signal indicative of an occurrence of one of the Events, and for determining the data path origin of the Event based upon the received signals;

wherein the Events include detection of;

a loss of signal;

alarm condition;

out of frame condition;

cyclic redundancy check errors;

framesynchronizationbit errors;

presence of an alarm indication signal;

presence of a remote alarm indication;

line code violation;

controlled slip; and

excess zeros;

wherein the monitoring device transmits a variant of a conventional alarm indication signal in response to detection of conditions which would otherwise lead to transmission of an alarm indication signal from the customer installation; and

wherein the variant of the alarm indication signal is a pattern of unframed ones in which a portion of the pattern has been modified to include a predetermined number of zeros.

15. The system of claim 14, wherein at least one of the at least one monitoring devices is located at a network interface.

16. The system of claim 15, wherein the monitoring device alters performance report messages in response to detection of one of the Events on the signal received by the monitoring device from the customer installation.

17. The system of claim 15, wherein the monitoring device alters performance report messages in response to detection of one of the Events on the signal received by the monitoring device from the network.

18. The system of claim 15, wherein the sectionalizer device is located within equipment under the control of the local exchange carrier.

19. The system of claim 18, wherein the sectionalizer device includes a communication device for communicating the location of the origin of the Event to a user without disrupting traffic on the data path.

20. The system of claim 18, wherein the communication device is a display device which is capable of displaying the location of the origin of the Event to a user.

21. The system of claim 19, wherein the communication device is coupled to an operations system for reporting to the operations system the location of the origin of the Event.

22. The system of claim 14, wherein the predetermined number of zeros is not great enough to prevent the variant from being included within the definition of a conventional alarm indication signal.

23. A system for generating information regarding the origin of Events in a data path and determining the origin of the Events based upon the generated information, including:

(a) at least one monitoring device capable of monitoring signals on the data path to detect either the Events or a signal indicative of an occurrence of one of the Events; and

(b) a sectionalizer device coupled to the at least one monitoring device for receiving data indicating which of the at least one monitoring devices has detected either one of the Events or a signal indicative of an occurrence of one of the Events, and for determining the data path origin of the Event based upon the received signals; and

a test and monitoring device disposed within a local exchange carrier, wherein the sectionalizer device is disposed within the test and monitoring device;

wherein the test and monitoring device is adapted to transfer signals received from a first of the at least one monitoring device to a second of the at least one remote monitoring device, monitor signals received from the first remote monitoring device, transfer signals received from the second remote monitoring device to the first remote monitoring device, and monitor the signals received from the second remote monitoring device.

24. The system of claim 23, wherein the test and monitoring device is an Integrated Transport Access Unit.

25. The system of claim 23, wherein the first monitoring device transmits a variant of a conventional alarm indication signal in response to detection of conditions which would lead to transmission of an alarm indication signal have been detected on the signal from the customer installation.

26. The system of claim 25, wherein the variant of the alarm indication signal is a pattern of unframed ones in which a portion of the pattern has been modified to include a predetermined number of zeros.

27. The system of claim 26, wherein the predetermined number of zeros is not great enough to prevent the variant from being included within the definition of a conventional alarm indication signal.

28. The system of claim 25, wherein the sectionalizer device determines that one of the Events originated within the local exchange carrier upon detection by the test and monitoring device that the first monitoring device has transmitted a variant of a conventional alarm indication signal.

29. A sectionalizer within a system for determining the status of a telecommunications circuit, having a monitoring device located between the telecommunications circuit and a customer installation for generating data derived from the content of signals received by the monitoring device over the circuit and transmitting the generated data, the sectionalizer including:

(a) receiving means for receiving the generated data from the monitoring device;

(b) detecting means, coupled to the receiving means for detecting that one or more Events have occurred; and

(c) determining means, coupled to the detecting means and the receiving means, for determining, based upon the received data and in response to detection of one of the Events by the detecting means, in which portion of the circuit from among multiple circuit portions the Event originated;

wherein signals transmitted over the circuit include both a payload and overhead, and the signals received by the sectionalizer device from the monitoring device indicate both inability to detect a payload and degradation of the signal due to errors in either the payload or the overhead.

30. The sectionalizer of claim 29, wherein the means for determining in which portion of the circuit the Event originated determines in which of the following portions of the circuit the Event has originated:

(a) a portion of the data path which lies between customer premises equipment and the monitoring device;

(b) a portion of the data path which lies between the monitoring device and the sectionalizer device;

(c) a portion of the data path which lies between the sectionalizer device and the monitoring device; and

(d) a portion of the data path which lies between the monitoring device and the customer premises equipment.

31. The sectionalizer of claim 29, wherein the sectionalizer further includes means for communicating to an Operations System whenever one of the Events is initially detected or ceases to occur.

32. The sectionalizer of claim 29, wherein data transmitted by the monitoring device is sent in an overhead channel of the circuit.

33. The sectionalizer of claim 29, further including a filter that time correlates detected Events.

34. The sectionalizer of claim 33, wherein the filter delays the processing of the data received by the sectionalizer device for a predetermined amount of time, the delay beginning at the time a new event is reported.

35. The sectionalizer of claim 34, wherein the Events detected by either the monitoring device or the sectionalizer are assigned an event level, and the filter delays are terminated if the received data includes an event level which is greater than a subsequently received event level.

36. A sectionalizer within a system for generating information regarding the origin of one or more Events in a data path and determining the origin of the respective Event based upon the generated information, having at least a first and second remote monitoring device each capable of monitoring signals on the data path to detect either the Event or a signal indicative of an occurrence of the Event, the sectionalizer including:

(a) a sectionalizer device adapted to be coupled to the at least one monitoring device, and including;

(1) a receiver which receives signals indicating which of the first and second remote monitoring devices has detected either the Event or a signal indicative of an occurrence of the Event; and

(2) a processing device for determining the origin of the Event based upon the received signals;

further including a test and monitoring device disposed within a local exchange carrier, wherein the sectionalizer device is disposed within the test and monitoring device;

wherein the test and monitoring device transfers signals received from the first remote monitoring device to the second remote monitoring device, monitoring signals received from the first remote monitoring device, transferring signals received from the second remote monitoring device to the first remote monitoring device, and monitoring the signals received from the second remote monitoring device.

37. The sectionalizer of claim 36, wherein the first monitoring device transmits a variant of a conventional alarm indication signal in response to detection of conditions which would lead to transmission of an alarm indication signal if detected by the monitoring device on the signal from the customer installation.

38. The sectionalizer of claim 37, wherein the variant of the alarm indication signal is a pattern of unframed ones in which a portion of the pattern has been modified to include a predetermined number of zeros.

39. The sectionalizer of claim 38, wherein the predetermined number of zeros is not great enough to prevent the variant from being included within the definition of a conventional alarm indication signal.

40. The sectionalizer of claim 37, wherein the sectionalizer determines that the Event originated within the local exchange carrier upon detection by the test and monitoring device that the first monitoring device has transmitted a variant of a conventional alarm indication signal.