Abstract: Described herein is a method for processing an invalidation of a downlink data tunnel between networks. The method includes the following steps: (1) a core network user plane anchor receives an error indication of data tunnel sent from an access network device, (2) after deciding that the user plane corresponding to the error indication uses a One Tunnel technology, the core network user plane anchor notifies a relevant core network control plane to request recovering the downlink data tunnel, (3) the core network control plane recovers the downlink data tunnel and notifies the core network user plane anchor to update information of the user plane. In addition, a communication system and a communication device are also provided. The method, system, and device can improve the speed of recovering data transmission after the downlink data tunnel becomes invalid.

Abstract: A system and method automatically learns mailbox configuration conventions. The validator module determines a valid set of configuration parameters used for accessing an electronic mailbox of a user within a mail domain after receiving configuration information from the user that is limited in the configuration parameters required for accessing the electronic mailbox. A learner module accepts from the validator module a set of configuration parameters determined to be valid and generates configuration conventions for a mail domain. A database store is the generated configuration conventions. The validator and learner modules can be operative as part of a web server.

Abstract: A redundancy control method is disclosed that controls a first redundancy function that switches between a working line and a protection line in response to a detection of a line error and a second redundancy function that performs a path switching in response to a detection of a path error in a ring network operating at a path rate lower than a line rate thereof. The method comprises a step of masking the path error detection within a period from a time of the detection of the line error to an expected time of the detection of the path error.

Abstract: A system and method automatically learns mailbox configuration conventions. The validator module determines a valid set of configuration parameters used for accessing an electronic mailbox of a user within a mail domain after receiving configuration information from the user that is limited in the configuration parameters required for accessing the electronic mailbox. A learner module accepts from the validator module a set of configuration parameters determined to be valid and generates configuration conventions for a mail domain. A database store is the generated configuration conventions. The validator and learner modules can be operative as part of a web server.

Abstract: An apparatus is provided for testing a communications line. The apparatus comprises a spool having at least eight terminals, and a length of wire wound on the spool. The wire has at least four subpairs of wires, each of which has opposite ends. A first end of each of the subpairs of wires is electrically connectable to the communications line, and a second end of each of the subpairs of wires is electrically connected to a corresponding terminal on the spool.

Abstract: A method and system is disclosed for testing an IDSL communications line. Transmission elements are queried sequentially within an IDSL communications line. A predetermined period of time is waited after querying a transmission element for a correct response. If a correct response is received, the next transmission element is queried for its existence. Configuration of the IDSL communications line is identified based on the received responses.

Abstract: A method is provided for communicating on an equipment network. According to the method, a message is sent from a sending equipment unit to a receiving equipment unit as a signal having a nominal power. Whenever the signal is amplified by an intermediate equipment unit through which the signal passes, the message is modified to indicate that the signal has been amplified by the intermediate equipment unit. Also provided is a first equipment unit for connection to an equipment network.

Abstract: An internetwork that is especially designed to seamlessly compensate for a failure in the system, and to allow the testing of modifications to the system, without interrupting the normal systems operations. The internetwork is especially useful for financial services and related transaction data where the users of that data and/or services are located in multiple branch offices physically separated from each other and from the data and/or services desired. The internetwork includes a modularized communications system, wherein users are connected to specific modules, and each of the modules operates preferably at less than 50% capacity. In more preferred embodiments, each module includes dual (b)routers for connecting to a core tier and separate dual (b)routers for connecting to the users.

Abstract: An apparatus and method for testing a telecommunication system, which runs telephony applications such as voice-mail, telephone banking systems, automated directory assistance, and multi-branched telephone customer service systems. The apparatus includes a test computer for scheduling and controlling the execution of test scripts, which include commands for generating network signaling, voice data, and digital data used to simulate transactions that typically take place on the telecommunication system; a database for storing the test scripts, test script input data, and test results; channels for running multiple test scripts in parallel; and, serial and voice ports for transmitting and receiving voice data and digital data to and from the telecommunication system.

Abstract: A repeater apparatus includes a first trunk circuit for receiving and sending data input from and to a first section of the communication link and a second trunk circuit for receiving and sending data input from and to a second section of the communication link. An Isolating circuit is connected to the first trunk circuit for electrically isolating the first section from the second section. For protecting against an overvoltage condition from the communication network, a protection circuit is operatively connected to the first and second trunk circuits. A controller has a first receiver/transmitter circuit for transmitting data from the first trunk circuit to the second trunk circuit, and a second receiver/transmitter circuit for transmitting data from the second trunk circuit to the first trunk circuit. The controller also produces a signal for indicating the completion of data transmission by the first and second receiver/transmitter.

Abstract: A ground fault detector for TI span equipment for transmitting signals from a central office to a network interface unit and receiving signals at the central office from the network interface unit. The TI span equipment includes a first pair of cables for transmitting data payload from the central office to the network interface unit and a second pair of cables for receiving data payload at the central office from the network interface unit. A line repeater is located along the TI span equipment between the central office and the network interface unit. The line repeater includes a transformer with core and a first, second, third and fourth coil. The coils are coupled to the transmit and receive span, and the transformer core saturates when the current differential between the coils exceeds a predetermined level. When the core is saturated, signals present on the first coil are not imposed on the second coil.

Abstract: A feed imbalance detector in a repeated line for detecting a feed imbalance in a PCM repeated line and for displaying an alarm includes: a constant current feeder for transmitting an operating voltage to the repeated line; a virtual ground unit for detecting the voltage difference between a plus output port and a minus output port of the constant current feeder; a comparator for comparing the voltage difference with a ground voltage, a detector for determining feed imbalance based on the output level value of the comparator after a predetermined detection time and for outputting a driving signal if feed imbalance is detected, and a display for displaying an alarm upon receiving the driving signal.

Abstract: A computer system employs a repeater unit which repowers a serial channel link. The repeater unit also monitors and records non-idle usage and errors for both directions of the repeated serial link. Non-idle usage of the serial link is recorded as a number of seconds that non-idle traffic flowed in the link over a given period of time. Link serial code violations and loss-of-light transitions are also counted. Link code violations are counted with an accuracy that permits targeted serial link bit-error rates, of no more than one bit error in approximately two months, to be accurately verified for the first time in a normal customer environment. The repeater unit permits an attached monitoring computer to read and reset all its usage and error counters as often as required by the customer, and without losing any counts of any counted event.

Abstract: A system is provided on an Integrated Multiport Repeater (IMR) to monitor the activity of the IMR when the repeater is in minimum mode. Through this system the serial output pin outputs status based upon inputs at two input pin the signal in and the clock signal. In a preferred embodiment there are four different status outputs, partition, loopback/link, Bitrate and SQE/Polarity. This system finds use in low end applications where complex control circuitry is not desired.

Abstract: A telephone line repeater (28) includes a pattern decoder/recognizer (100) which recognizes, inter alia, an input interrogating signal transmitted on a telephone network (20). The interrogating signal includes an address field (302) having at least one subfield (304) therein. The pattern decoder (100) determines that its repeater (28) is to be tested, if a predetermined subfield (304) of the interrogating signal is configured according to a predetermined select convention. When the repeater (28) recognizes that it is being addressed, a controller (110) causes the addressed repeater to "loop back", returning, in alternating sequence, test-indicative no-operation signals and diagnostic information ("DSM") signals generated by the repeater. Methods for testing a repeater and methods for testing telephone networks are also disclosed.

Abstract: A transmission line switching system for switching a transmission line in operation to another transmission line when a fault occurs in the transmission line during operation comprising: a transmission line in operation constituted by a plurality of terminal repeaters, a plurality of circuit switching apparatuses, and a plurality of transmission cables, all connected in series; and another transmission line provided between a head terminal repeater and an end terminal repeater; wherein when a transmission cable is completely disconnected, information input from the head terminal repeater is returned from a terminal repeater located just before a disconnection in the transmission cable to the head terminal repeater, transferred from the head terminal repeater to the end terminal repeater through the another transmission line, returned from the end terminal repeater to a terminal repeater located just after the disconnection in the transmission cable, and returned to the end terminal repeater.

Abstract: A T1 digital carrier system having a transmitter, receiver and a plurality of intermediate repeater stages. Each remote repeater has a select switch for automatically selecting that the remote repeater be placed in loop-back mode should a combination of framing bits occur in the serial bit stream that matches that said remote repeaters address therein, thereby allowing remote testing of the communications link and repeaters. In addition, no additional test lines are required to verify a T1 communications link.

Abstract: A step-by-step locating system for a digital bidirectional transmission link includes repeater pairs between a monitoring end equipment and a remote monitored end equipment. When a repeater pair is connected via a loop-back path to the monitoring end equipment thereby testing the repeater pair, the next repeaters are also connected to the monitoring equipment by closure of associated switches. Such a condition avoids the need for matching with maximum amplification gain in equalizers of the next repeaters, which could cause a fault in the regeneration of remote locate sequences or untimely looping in the next pairs after testing of the looped repeater pair. In practice, any interruption of the digital signal in remote locate sequences transmitted by the monitoring equipment does not exceed a width such that no matching with maximum gain is generated.

Abstract: A method of transmitting signalling along a bidirectional digital transmission link consists in transmitting from an intermediate equipment of the link a signalling message in two parts. One is a characterizing part the form of which depends on the signalling type and which is substituted for data of one of the digital bit streams carried by the link in the direction from one of the terminals referred to as the processing terminal. The other is a localizing part whose form is independent of the signalling type and which is substituted for data of the digital bit stream carried by the link in the direction towards the other, so-called relay terminal. The relay terminal responds by sending an acknowledgement message to the processing terminal, the time-delay of this relative to the characterizing part being used to identify the sending equipment. A signalling message transmission circuit controls switching circuits inserted into the paths of the digital bit streams carried by the link.

Abstract: A digital transmission line fault location signal generator includes a maximal length linear feedback shift register having m stages for generating a first pseudorandom sequence of binary signals with a period 2.sup.m -1. The first pseudorandom sequence of binary signals is delayed by n time slots into a second pseudorandom sequence of binary signals. A circuit merges the first and second pseudorandom sequences of binary signals into a combined sequence of signals on the digital transmission line.

Abstract: A fault location system includes a test code generator located at an end terminal for transmitting a test code sequence of signals onto a digital transmission line. A line regenerator located along the transmission line detects the test code sequence of signals. Other circuitry interconnected with the line regenerator determines and stores a number count indicating how many errors are detected in the test code sequence. In response to a polling request from a fault location circuit in the end terminal, the other circuitry storing the count indicating errors transmits that count to a fault location circuit which calculates an error rate therefrom.

Abstract: An in-service line monitoring technique to detect and isolate marginal and failed digital transmission equipment within a digital telecommunication system having at least two end terminals. At selected terminal and repeater locations, a digital error detector monitors the bit error rate for each location. The detected BER is truncated to include at least the most significant digit and the exponent of the BER. The truncated BER is stored and then encoded for transmission back to the command center usually located at an end terminal. At the one end terminal the encoded BER is stored and displayed upon request. By being able to monitor the truncated BER at any location or direction, maintenance personnel are able to determine when a link in the system is beginning to deteriorate well before a complete path failure occurs.

Abstract: In-service line monitoring apparatus to detect and isolate marginal and failed digital transmission equipment within a digital telecommunication system having at least two end terminals. At selected terminal and repeater locations, a digital error detector monitors the bit error rate for each location. The detected BER is truncated to include at least the most significant digit and the exponent of the BER. The truncated BER is stored and then encoded for transmission back to the command center usually located at an end terminal. At the one end terminal the encoded BER is stored and displayed upon request. By being able to monitor the truncated BER at any location or direction, maintenance personnel are able to determine when a link in the system begins to deteriorate well before a complete path failure occurs.

Abstract: An optical repeater for an optical digital transmission line has a pair of in-service monitoring circuits (55, 55') each of which includes a flip-flop (57) for dividing frequency of transmission data to derive commands and burst carrier in the first line (54). A counting means (59, 61) is provided for detecting parity errors and counting the errors in an opposite second line (65). A timing generation means (62) is provided for reading out the counting means (61) upon receipt of the burst carrier. A phase modulator (64) provides phase modulation to a clock pulse in an opposite second line (65) according to the output of the timing generation means (62). The number of errors in the second line (65) is stored in the counting means (61) according to commands in a first line (54) from a terminal transmitter (52). The content of the counting means (61) is forwarded to a terminal receiver (66) through phase modulation of clock pulses in a second line (65) upon receipt of the burst carrier.

Abstract: Method and apparatus is disclosed for identifying faults in a subscriber carrier telephone system utilizing out-of-band pilot signals and comprising pluralities of cables and repeaters that are alternately connected in series between carrier equipment at a central office location and a subscriber station. Equipment at the office location transmits selected numbers of test pulses, having a test frequency that is between the transmitted and received channel and pilot frequencies, to the first cable. The pulses are detected at the first repeater and counted. A microprocessor is responsive to the test pulse count in the repeater for initiating associated tests on the cable and/or repeater, or for retransmitting test pulses on the next cable to the next repeater for causing it it perform designated tests. The results of the tests are sent to the office equipment in the form of reply pulses having a frequency that is below the lowest channel frequency.

Abstract: Method and apparatus is disclosed for identifying faults in a subscriber carrier telephone system utilizing out-of-band pilot signals and comprising pluralities of cables and repeaters that are alternately connected in series between carrier equipment at a central office location and a subscriber station. Equipment at the office location transmits selected numbers of test pulses, having a test frequency that is between the transmitted and received channel and pilot frequencies, to the first cable. The pulses are detected at the first repeater and counted. A microprocessor is responsive to the test pulse count in the repeater for initiating associated tests on the cable and/or repeater, or for retransmitting test pulses onto the next cable to the next repeater for causing it to perform designated tests. The results of the tests are sent to the office equipment in the form of reply pulses having a frequency that is below the lowest channel frequency.

Abstract: Method and apparatus is disclosed for identifying faults in a subscriber carrier telephone system utilizing out-of-band pilot signals and comprising pluralities of cables and repeaters that are alternately connected in series between carrier equipment at a central office location and a subscriber station. Equipment at the office location transmits selected numbers of test pulses, having a test frequency that is between the transmitted and received channel and pilot frequencies, to the first cable. The pulses are detected at the first repeater and counted. A microprocessor is responsive to the test pulse count in the repeater for initiating associated tests on the cable and/or the repeater, or for retransmitting test pulses on the next cable to the next repeater for causing it it perform designated tests. The results of the tests are sent to the office equipment in the form of reply pulses having a frequency that is below the lowest channel frequency.

Abstract: To perform a loopback condition for testing purposes, the present apparatus supplies a null signal from an end terminal on a communication link through a set of repeater stations to reinitialize the repeater stations. It then sends N+1 pulses of a frequency different than the data frequency through the repeater stations with each repeater station that receives more than two pulses disgarding one pulse and forwarding the rest. The repeater station or remote end terminal that receives only two pulses reconfigures itself to a loopback condition, returns a null signal back to the end terminal originally transmitting the N+1 pulses and then sends an acknowledgement pulse. Data signal testing can then be performed until a further null condition is sent thereby reinitializing the repeater stations to the data transmission configuration.