Abstract: A method and apparatus for reducing the vulnerability of the telecommunications system to unauthorized use that is easy to implement and that can reduce the instances of unauthorized access even during periods when telecommunications personnel are not able to give attention to the traffic on the system. The telecommunications system collects statistics of each user's pattern of telecommunications usage. Typically, these statistics will be in the form of, say, the average number of calls per day or the average number of calls per day on given days of the week. It may also include the mean busy hour for the given days of the week. Moreover, daily averages may be taken not only for all calls but also for all calls of a particular type, e.g., of all international calls. These statistics are taken for a reference period, such as the preceding thirty days, and the corresponding quantity for the current day is also computed.

Abstract: A method and apparatus for reducing the vulnerability of the telecommunications system to unauthorized use that is easy to implement and that can reduce the instances of unauthorized access even during periods when telecommunications personnel are not able to give attention to the traffic on the system. The telecommunications system collects statistics of each user's pattern of telecommunications usage. Typically, these statistics will be in the form of, say, the average number of calls per day or the average number of calls per day on given days of the week. It may also include the mean busy hour for the given days of the week. Moreover, daily averages may be taken not only for all calls but also for all calls of a particular type, e.g., of all international calls. These statistics are taken for a reference period, such as the preceding thirty days, and the corresponding quantity for the current day is also computed.

Abstract: A method and apparatus for reducing the vulnerability of the telecommunications system to unauthorized use that is easy to implement and that can reduce the instances of unauthorized access even during periods when telecommunications personnel are not able to give attention to the traffic on the system. The telecommunications system collects statistics of each user's pattern of telecommunications usage. Typically, these statistics will be in the form of, say, the average number of calls per day or the average number of calls per day on given days of the week. It may also include the mean busy hour for the given days of the week. Moreover, daily averages may be taken not only for all calls but also for all calls of a particular type, e.g., of all international calls. These statistics are taken for a reference period, such as the preceding thirty days, and the corresponding quantity for the current day is also computed.

Abstract: A method and apparatus for reducing the vulnerability of the telecommunications system to unauthorized use that can reduce the instances of unauthorized access. The telecommunications system collects statistics of each user's pattern of telecommunications usage. Typically, these statistics will be in the form of, say, the average number of calls per day or the average number of calls per day on given days of the week. These statistics are taken for a reference period, such as the preceding thirty days, and the corresponding quantity for the current day is also computed. If the current statistics are not excessive as compared with the reference statistics, then access to a communications resource is granted. But if a predetermined deviation is found then a supplemental restriction is placed upon the call.

Abstract: A method and apparatus for reducing the vulnerability of the telecommunications system to unauthorized use that is easy to implement and that can reduce the instances of unauthorized access even during periods when telecommunications personnel are not able to give attention to the traffic on the system. The telecommunications system collects statistics of each user's pattern of telecommunications usage. Typically, these statistics will be in the form of, say, the average number of calls per day or the average number of calls per day on given days of the week. It may also include the mean busy hour for the given days of the week. Moreover, daily averages may be taken not only for all calls but also for all calls of a particular type, e.g., of all international calls. These statistics are taken for a reference period, such as the preceding thirty days, and the corresponding quantity for the current day is also computed.

Abstract: A method and apparatus for reducing the vulnerability of the telecommunications system to unauthorized use that is easy to implement and that can reduce the instances of unauthorized access even during periods when telecommunications personnel are not able to give attention to the traffic on the system. The telecommunications system collects statistics of each user's pattern of telecommunications usage. Typically, these statistics will be in the form of, say, the average number of calls per day or the average number of calls per day on given days of the week. It may also include the mean busy hour for the given days of the week. Moreover, daily averages may be taken not only for all calls but also for all calls of a particular type, e.g., of all international calls. These statistics are taken for a reference period, such as the preceding thirty days, and the corresponding quantity for the current day is also computed.

Abstract: An access-control module (22) is used in connection with a conventional private branch exchange (12) to control direct inward service access (DISA), by which callers calling in on one trunk are afforded access to an outgoing trunk or other destination within the PBX environment. The access-control module (22) is simply plugged into an existing extension, and the PBX (12) initially directs to that extension all calls from the incoming trunk. The access-control module (22) receives the users' authorization code and desired destination and then signals the PBX in the normal manner to transfer the call to an outgoing trunk or other destination within the PBX environment if the incoming call meets certain criteria imposed by the access-control module (22).

Abstract: A call-disposition analyzer (10) for determining whether calls placed by way of a private branch exchange (PBX) (12) have been completed employs current sensors (22) to monitor the trunk lines (16) that the PBX (12) uses. It thereby records the telephone numbers dialed over the trunk lines (16). It also detects supervisory and voice signals on the trunk lines (12) so as to determine of the call's disposition--i.e., typically, so as to determine whether the call went through successfully. It stores in a memory (60) the call-disposition estimate and tags it with the telephone number that was dialed to make the call.

Abstract: A special services add-on specifically adapted for use in a dial pulse activated telephone switching office such as a step-by-step office to enable the addition of various modern features thereto, thereby extending the economic life of the office. The add-on is a stored program, processor based system that can be put into service on a line-by-line basis independent of subscriber line assignments. Among the special services provided by the add-on are incoming call alert, call conferencing, call forwarding, tone dialing, abbreviated dialing, instant recall, restricted calling, ringback, delayed ringback and ring disable. Various of the services are remotely controllable by the subscriber by dialing programming instructions to the add-on either from his own or another telephone subset.