Abstract: A communication device includes a time switch array unit which performs a switching of transmission lines. A switch unit performs a switching connection from a protection channel line among the transmission lines to a working channel line, for each channel formed in the transmission lines. A bridge unit performs a switching connection from a working channel line among the transmission lines to a protection channel line, for each channel formed in the transmission lines. A control unit performs a recovery of a signal transmission on the working channel lines by controlling the switching connections of the switch unit and the bridge unit.

Abstract: Disclosed is an ATM exchange for granting permission to a camp-on request in a short time.A temporarily saved band value management table for managing temporarily saved band value is provided, as is a band management table for managing empty band value in the storage device of an ATM exchange comprising a storage device, a control device, and the like. The control device selects a corresponding empty band value for a temporarily saved band value when a first camp-on request is received from a terminal, and sets the empty band value to "0." In addition, the control device adds to the temporarily saved band value a band value released by a break in communication when a camp-on request is registered, and grants permission for communication to the terminal that has issued this camp-on request when the temporarily saved band value is higher than the band value required by a registered camp-on request.

Abstract: A method for communicating packetized data over a communications link having a predetermined format including a framing using a channel bank having a time division multiplexing addressing scheme is disclosed in which a plurality of channel units may generate packetized data and the communications link may be allocated to a channel unit that is currently sending data over the communications link. The next sender of packetized data over the communications link may be determined by a system distributed over the plurality of channel units so that each channel unit independently determines whether it is the next sender. The communications link may be allocated to the channel unit that is the next sender of packetized data after the current sender of packetized data so that the time division multiplexing addressing scheme of the channel bank is ignored and the channel bank communicates packetized data. An apparatus for communicating packetized data over a channel bank is also disclosed.

Abstract: A system consisting of a repeater management function and media access control into a single device. The repeater management functions and the media access control may also be combined with bridging support functions. The repeater management function uses a repeater management interface to control information transferred to an access port and to control repeater functions under direction of access port and monitor repeater function and provide status via access port and to control the bridge support function. The bridge function controls information transferred through a bridge port. The MAC function transfers information between the repeater data port and the MAC port (transmit/receive). The integration of the media access controller and repeater management into a single device is independent of the implementation of any of the ports.

Abstract: An ATM switch system having a traffic control function to reduce cell loss probability and delay of cells communicated through a network to be equal to or less than acceptable values, respectively. To achieve traffic control function, the invention provides a circuit to observe the queue of cells in the buffer, and an overflow testing circuit for obtaining a distribution of the queue size according to observed values of the queue and testing to decide, according to the distribution, whether an event has occurred that the cell loss probability is shifted due to the input cells to a distribution related to a cell loss probability exceeding an upper-limit value of acceptable cell loss probability.

Abstract: The object of the invention is to provide a method and a circuit for a crosspoint buffer-type self-routing switch circuit in an ATM switch that allows a switch of higher speed and greater efficiency with a more compact hardware construction and without complicated circuit configuration or operation.

Abstract: A line protection switching system of a duplexed fiber interface shelf makes easily to reconcile conditions of duplexed fiber interface shelves, which perform line switching by employing APS bytes on an ISDN network. The line protection switching system has a pair of duplexed line switching controllers that send a line switching control signal to switch the transmission lines and a pair of duplexed line interface devices operatively connected to the pair of duplexed line switching controllers. An active interface device of the duplexed interface devices receives the line switching control signal only from an active line switching controller of the duplexed line switching controllers and echoes the received control signal back to the duplexed line switching controllers.