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:
The quality and performance of the connectionless communications system are improved. When a BOM is received, the destination address DA of the L3-PDU stored in the payload of the BOM is retrieved, and the tag information is obtained from the DA (S11). The output message identifier MID is reserved (S12), and the tag information and output MID are assigned to the BOM (S13). Then, the tag information and output MID are written to the table. When a COM is received, the tag information and output MID are retrieved using the MID of the COM as a key, and the information is provided for the COM (S31 and S32). When an EOM is received, the tag information and output MID are retrieved using the MID of the EOM as a key, and the information is provided for the EOM (S41 and S42). Then, the output MID is released (S43).
摘要:
A switch station including an ATM switch; a memory storing control data for operations of the switch station; an intra-station device, accommodating a subscriber line, performing communication operation on subscriber ATM cell; a control processor generating control information in link access protocol (LAP) format; and an interface unit converting LAP control information into ATM cell to the intra-station device through the ATM switch, wherein the control information is communicated according to LAP, the intra-station device receives the control information and transmits a direct memory access request to obtain control data stored in the memory, the interface unit obtains and converts the data format of the control data into ATM cell to transmit to the intra-station device through the switch, and the intra-station device performs the communication operation on the subscriber ATM cell based on the control data received through the switch.
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 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 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 self-routing exchange which includes switch modules connected in multiple stages. A synchronous transfer mode (STM) circuit switch module, which is capable of changing over a connection relationship between incoming highways and outgoing highways, is provided between the multistage-connected switch modules and self-routing switch modules. Asynchronous transfer mode (ATM) switch modules are provided as switch modules in preceding and succeeding stages of the circuit switching module. In dependence upon the number m of self-routing switch modules, a controller sets, by means of software, the connection relationship between the incoming and outgoing highways in each of space switches incorporated within the circuit switching module. As a result, the total mn-number of incoming highways from the self-routing switch modules are connected to respective ones of mn-number of outgoing highways set by the controller. In a case where self-routing switch modules are added on later to expand the system, the controller changes the connection relationship between the incoming and outgoing highways in each space switch within the circuit switching module, using software.
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.