摘要:
When broadcast is executed in an ATM mode, a subscriber is assigned a path and a channel as information by a central controller of a switching unit, and the information is added to a cell to be transmitted to the switching unit through a subscriber line. The switching unit comprises the central controller, a tag information adder, and a self-routing switch. The self-routing switch comprises a plurality of input lines and output lines, and unit switches provided for each input line corresponding to each of the output lines. The tag information adder adds routing information for the self-routing switch to a cell to be transmitted to the self-routing switching. The routing information comprises a set of bits corresponding to each output line, and the tag information adder adds to the cell the routing information in which a bit corresponding to an output line for transmitting the cell is set to a predetermined logical value. In executing the broadcast, a plurality of bits corresponding to a plurality of output lines are set to a predetermined logical value. The self-routing switch analyzes the routing information of the cell received by each unit switch, and outputs the cell to the outpost line if the bit corresponding to a unit switch is set to a predetermined logical value. If a plurality of bits of routing information are set to a predetermined value, the cell is outputted from a plurality of output lines, thus enabling the broadcast.
摘要:
A switch interface unit, a monitor unit, and a control system interface unit are connected as external units to a highway to which a subscriber information processing unit is also connected so that a monitoring process, that is, a special study process, can be simplified and a cost charged for the subscriber information processing unit can be prevented from increasing greatly. Furthermore, in an accounting process, accounting parameters are accumulated in an accounting information accumulating unit for variations on compressed source addresses, not on source addresses. As a result, the accounting information accumulating unit, etc. can be realized with normal circuit elements only.
摘要:
A first terminal unit is connected to a line switch via a set of data lines. A second terminal unit is connected to the first terminal unit via a set of data lines. A third terminal unit is connected to the second terminal unit via a set of data lines. Therefore, the terminals are sequentially connected in series. Cells transmitted to the terminals are multiplexed by each terminal and sequentially transmitted upstream, to the third terminal unit, the second terminal unit, and the first terminal unit together with a token. Since the first terminal unit receives a first identification signal from a switch and a second identification signal from downstream, the first terminal unit recognizes that it is the highest order terminal unit, and sends a cell to the switch after separating the cell from a token which is to be returned downstream. Since the second terminal unit does not receive the first identification signal and receives only the second identification signal, it recognizes that it is an intermediate terminal unit, and sends back downstream a token returned from upstream. Since the third terminal unit does not receive the identification signals, it recognizes that it is the lowest order terminal unit, and sends upstream a cell transmitted via a low data rate line according to a token returned from upstream.
摘要:
A cell having an attribute of a point-to-multipoint connection is distributed to each of a number of subscribers using a point-to-multipoint connection distributing switch to be provided in parallel with a point-to-point connection, concentrating and distributing switch. Therefore, a hardware configuration can be simply established. Besides, both a point-to-point connection, and a point-to-multipoint connection can be made only by switching a cell to each switching unit, and a software configuration can thus be simplified.
摘要:
A broadband ISDN remote multiplexer, which is constructed by separating a subscriber line interfacing section from an ATM exchange and installing the same at a remote location connected via a high-speed transmission line, comprises: a first interface unit for carrying out conversion between a transmitted signal of UNI format, carrying a destination number in its GFC field and transmitted over a transmission medium interconnecting the ATM exchange and the broadband ISDN remote multiplexer, and a first path-control signal that directs a connection within the remote multiplexer in accordance with the destination number; a plurality of subscriber line interface units for terminating respectively the plurality of broadband ISDN subscriber lines; and a multiplexing/demultiplexing unit for making a connection between the first interface unit and each of the subscriber line interface units in accordance with the first path-control signal.
摘要:
In a data access device for writing into or read from a data conversion table on the basis of a clock signal extracted from a cell being transferred over a line, a clock signal generator of the invention generates a second clock signal which differs from the first clock signal extracted from an incoming cell. A write/read control unit writes data into or reads data for maintenance from the data conversion table on the basis of either the first clock signal or the second clock signal when the line is normal. In the event of the occurrence of a failure in the line, on the other hand, the write/read control circuit permits the data conversion table to be written into or read from for maintenance on the basis of the second clock signal.
摘要:
A test system exactly checks the integrity of data in an ATM system, and generates a test cell of a desired band. In the first aspect of the system in which data stored in an ATM cell are transmitted in an 8-bit parallel format in the ATM system, a test cell generating device connected to an input line outputs a test cell having 1 in all of the eight bits or having zero in all of the eight bits, and the test cell confirming device connected to an output line of the ATM switch detects the above described data. In the second aspect, the test cell generating device provided in an input trunk outputs a test cell of a desired band based on a ratio between two optional integers N and n (N.gtoreq.n), the state of a buffer of the ATM switch is monitored, and a load test is conducted to determine whether or not any cell has been destroyed.
摘要:
An ATM transmission system transmits cell-formatted data in an asynchronous transfer mode, and aims at conducting an online path route test in the system. If one path route only is established in the system, then one or more valid cell detecting units for detecting, upon receipt of a cell enable signal indicating that a valid cell to pass through the path route has been sent, the arrival of a valid cell are provided at an optional point including an ATM switch in the path route so that the path route can be partially or entirely validity-checked. If plurality of valid path routes are established, the system provides, in addition to the valid cell detecting units, a virtual path identifier and virtual channel identifier comparing unit for comparing values of the VPI and VCI stored therein with values of a VPI and a VCI added to an arriving cell, and a path route validity check unit for partially or entirely validity-checking a path route in the ATM transmission system.
摘要:
An in-service activator for a broadband exchanger has a dual system structure, in which a first system and a second system form a dual pair. The first system and the second system in the dual pair each has at least one [1] channel converter and a switcher. A channel converter stores channel setting information for use in routing a cell inputted from a line, and outputs the cell inputted from the line by attaching the channel setting information to the cell. The switcher switches a cell outputted from a channel converter. The interfacer stores, in a channel converter of a to-be-activated standby system in the dual pair, the channel setting information read from the corresponding channel converter of an act system in the duplex pair.
摘要:
A sending trunk on the input side of an ATM switch is equipped with a test cell generating section, and a receiving trunk on the output side of the ATM switch is equipped with a test cell detecting section. The test cell generating section includes a unit for setting a test cell identifier in the header of a test cell and a unit for generating pieces of data with regularity in the information field of the test cell. The test cell detecting section includes a unit for detecting the test cell identifier from the header of a cell received and a unit for detecting regularity from data in the information field of the cell received. When a test cell is transmitted, the test cell detecting section evaluates the result of a test on the basis of the result of detection of the test cell identifier from the header of the test cell and the result of detection of the regularity from data in the information field of the test cell.