Method and apparatus for determining the origin of a remote alarm indication signal

• US 5,790,531 A
• Filed: 09/30/1996
• Issued: 08/04/1998
• Est. Priority Date: 12/23/1994
• Status: Expired due to Term

• Current Assignee: Viavi Solutions, Inc. (Lumentum Holdings Inc.)
• Original Assignee: Applied Digital Access, Inc. (Lumentum Holdings Inc.)
• Inventors: Wright, Maynard A., Hartmann, Paul R., Ellebracht, Edward T., Pope, Kevin T., Hecker, Ramone A.
• Primary Examiner(s): Chin, Wellington
• Assistant Examiner(s): VU, HUY DUY
• Application Number:
  US08/723,097
• Time in Patent Office: 673 Days
• Field of Search: 370/241, 370/242, 370/243, 370/244, 370/245, 370/246, 370/247, 370/248, 370/249, 370/250, 370/251, 370/252, 370/359, 370/360, 370/384, 370/420, 370/463, 370/527, 370/528, 370/529, 379/1, 379/2, 379/3, 379/4, 379/5, 379/6, 379/9, 379/10, 379/27, 379/28, 379/29, 379/33, 379/37, 379/47, 379/188, 379/199, 379/399, 340/825.06, 340/825.16, 340/825.17, 340/825.36, 340/825.37, 340/825.49
• US Class Current: 370/242
• 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. A Remote Alarm Indication-Customer Installation signal is generated to enhance the ability to sectionalize the data path.

Claims

1. A method for determining whether an alarm originated within customer premises equipment or network equipment within a telecommunication system, including the steps of:

(a) receiving at a network interface a first signal from a network;

(b) determining whether the first signal is in an alarm state;

(c) receiving at the network interface a second signal from a customer premises equipment;

(d) determining whether the second signal includes an indication that the signal received by the customer premises equipment from the network interface unit is in an alarm state; and

(e) if the first signal is not in an alarm state and the second signal indicates that the signal received from the network interface unit is in an alarm state, then sending from the network interface unit a third signal to the network, the third signal being an extended superframe format signal in which for a period of 90 milliseconds every 1.08 seconds, an unscheduled message "0000 0000 1111 1111" in the data link, which is transmitted with the right most bit being transmitted first, is replaced with a message "0011 1110 1111 1111" to indicate that the alarm indicated by the alarm state originated within the customer premises equipment.

2. A network interface unit for determining whether an alarm originated within customer premises equipment or network equipment within a telecommunication system, including:

(a) first receiver for receiving a first signal from a network;

(b) first means, coupled to the first receiver, for determining whether the first signal is in an alarm state;

(c) second receiver for receiving a second signal from a customer premises equipment;

(d) second means, coupled to the second receiver, for determining whether the second signal is an indication that the signal received by the customer premises equipment from the network interface unit is in an alarm state;

(e) third means, coupled to the second means, for generating a third signal, the third signal being an extended superframe format signal in which for a period of 90 milliseconds every 1.08 seconds an unscheduled message "0000 0000 1111 1111" in a data link, in which the right most bit is transmitted first, is replaced with a message "0011 1110 1111 1111";

(f) transmitter for sending from the network interface unit a third signal to the network, the third signal being an extended superframe format signal in which for a period of 90 milliseconds every 1.08 seconds, the unscheduled message "0000 0000 1111 1111" in the data link, which is transmitted from with the right most bit being transmitted first, is replaced with a message "0011 1110 1111 1111" to indicate that the alarm indicated by the alarm state originated within the customer premises equipment, if the first signal is not in an alarm state and the second signal indicates that the signal received from the network interface unit is in an alarm state.

3. A method for determining the origin of an alarm within a telecommunication system, including the steps of:

(a) receiving at a network interface unit a first signal from a network;

(b) determining whether the first signal is in an alarm state;

(c) transmitting from the network interface unit a second signal to customer premises equipment;

(d) receiving a third signal at the network interface unit from customer premises equipment;

(e) determining whether the third signal is an indication that the second signal received by the customer premises equipment from the network interface unit is in an alarm state;

(f) if the first signal is in an alarm state, then transmitting from the network interface unit to the network a fourth signal which indicates that the signal received by the customer premises equipment is in an alarm state; and

(g) if the first signal is not in an alarm state and the third signal indicates that the second signal is in an alarm state, then sending from the network interface unit a fifth signal to the network;

wherein the fifth signal is composed such that equipment specifically designed to detect the fifth signal as distinct from the fourth signal, so detects the fifth signal, and equipment not specifically designed to detect the fifth signal as distinct from the fourth signal detects the fifth signal as being the same as the fourth signal, such that specially designed equipment can distinguish between an alarm state that originates at the network and at the customer premises without disrupting the ability of equipment not specifically designed to detect the fifth signal from determining that an alarm state exists on one of the legs of the telecommunication system upstream of the customer premises equipment in response to receipt of the fifth signal.

4. The method of claim 3, wherein the fourth signal is a remote alarm indication signal.

5. The method of claim 3, wherein the fourth signal is an extended superframe format signal having unscheduled messages transmitted on the data link.

6. The method of claim 5, wherein the fifth signal is an extended superframe format signal in which at least one of the unscheduled messages that would have been transmitted if the first signal were in an alarm state is replaced with an unscheduled message after a time period which is sufficiently long to ensure that equipment not specifically designed to detect the fifth signal would detect the fourth signal prior to replacement with the unscheduled message of the fifth signal.

7. The method of claim 6, wherein the unscheduled message of the fifth signal that replaces the unscheduled message that would have been transmitted is sufficiently short not to disrupt the detection of the fifth signal as an indication of an alarm state by equipment not specifically designed to detect the fifth signal.