Abstract: An arrangement analyzes a plurality of call detail records and determines that a particular call processing code has occurred a predetermined number of times during a previously defined time interval. The fact of these multiple occurrences of these processing codes is determined to be an indication of a trunk failure. A maintenance request is issued to address the detected failure.

Abstract: A threshold-based call control facility is provided for use in a telecommunications network switch to control the processing of calls associated with so-called high capacity (HICAP) telecommunications services. In addition, a feature is provided for dynamically changing a respective threshold value at each network switch until the number of such calls reaching a respective destination switch, and hence an associated trunk group, reaches an optimum level, in which each such change in the value of the threshold is determined as a function of traffic data accumulated by the destination switch for the associated trunk group.

Abstract: "Transhybrid" loss is maximized in a transmission network of the active canceler type employed to couple receive and transmit unidirectional transmission paths to a bidirectional transmission path including 2-wire loaded type cable by controllably adjusting impedance elements of the canceler circuit in a prescribed sequence including adjustment of a network build out capacitor to obtain amplitude nulls of signals detected on the transmit path while supplying individual ones of a plurality of test signals to the receive path. The test signals include first and second signals having a plurality of equally spaced frequency components in first and second frequency bands, respectively, and a third signal having a predetermined single frequency.

Abstract: A bidirectional transmission path is typically coupled to unidirectional receive and transmit paths to effect amplification in repeaters or the like. A determination of whether the bidirectional path includes either loaded or nonloaded type 2-wire cable is made by inserting a test signal having a predetermined frequency and a predetermined amplitude into the receive path and measuring the peak amplitude of a transmit signal developed on the transmit path. If the transmit signal peak amplitude is greater than a predetermined threshold value, the 2-wire cable is considered loaded type, and if the transmit signal peak amplitude is less than the threshold value, the 2-wire cable is considered nonloaded type.

Abstract: "Transhybrid" loss is maximized in a transmission network of the active canceler type employed to couple receive and transmit unidirectional transmission paths to a bidirectional transmission path including 2-wire nonloaded type cable by controllably adjusting impedance elements of the canceler circuit in a prescribed sequence to obtain amplitude nulls of signals detected on the transmit path while supplying individual ones of a plurality of single frequency test signals to the receive path. The adjustment sequence comprises a first procedure including a plurality of iterative adjustments of predetermined impedance elements in predetermined groups until no changes in the impedance settings occur and multiple iterative adjustment of predetermined groups until no changes in the impedance settings occur.