JPH09181736A - Method for dealing with generation of trouble at fixed length cell exchange, interface device added to fixed length cell exchange, line concentrating device added to fixed length cell exchange, and fixed cell exchange - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable exact charging at all times by stopping charging concerning relevant connection until an alarm cell is stopped concerning an interface part receiving the alarm cell of cell multiplex/exchange layer. SOLUTION: When an interface part 3 receives the alarm cell outputted at the time of fault at the cell multiplex/exchange layer, at a fixed length cell exchange 1, that interface part 3 detects this alarm cell while using an alarm cell detection part 32 and stops the count of charging counter 31 concerning the relevant connection while using a charging counter control part 33. When the transmission stop of alarm cell is detected by the interface part 3, at the interface part 3, the count of charging counter 31 concerning the relevant connection is restarted by the control part 33. Thus, even when the fault of line layer or cell multiplex/exchange layer is generated, that fault is surely reported to the following-order station such as the other interface device, the count of charging counter is stopped and normal charging is enabled.

Description

Detailed Description of the Invention

[Technical Field of the Invention] [0001] Conventional technology (Fig. 23) Problem to be solved by the invention (Fig. 23) Means for solving the problem (Figs. 1 to 10) Embodiment of the invention (a ) Description of the first embodiment (FIGS. 11 to 16) (b) Description of the second embodiment (FIG. 17) (c) Description of the third embodiment (FIGS. 18 to 21) (d) Fourth embodiment Explanation (Fig. 22) Effect of the invention

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for coping with a failure in a fixed-length cell switch, an interface device equipped with the fixed-length cell switch, a line concentrator equipped with the fixed-length cell switch, and a fixed-length cell switch. As is well known in recent years, ATM (Asynchronous
Transfer Mode) Exchange technology was agreed by ITU-T, and B-
ISDN (Broadband aspects of Integrated Services
Research has been actively conducted in each institution as a technology for realizing the Digital Network).

[0003]

2. Description of the Related Art FIG. 23 is a block diagram showing a schematic structure of a general ATM switching network. As shown in FIG. 23, an ATM switching network is usually an ATM switching system 100 and a UNI (U
ser Network Interface) and NNI (Network Node Interf)
ACE) and other interface devices 201 to 203, and line concentrators (distribution) devices 301 to 303 for concentrating (or distributing) the input and output of each interface device 201 to 203. ATM switch 1 through the concentrators 301 to 303
It is designed to be connected to 00.

Here, the ATM exchange 100 is an AT which is transmitted and received through each of the interface devices 201 to 203.
Fixed-length data called M cells (usually 53-byte data consisting of a 5-byte header (control information section storing data transfer destination) and a 48-byte data section)
In the exchange that handles (1), each ATM cell can be asynchronously delivered (exchanged) to the transfer destination according to the header added to each ATM cell.

Therefore, in general, the ATM exchange 100 is
As shown in FIG. 23, an ATM switch (switching switch) 101 which automatically determines a transfer path of an ATM cell called a so-called self-routing switch according to its header, and an ATM switch 100 including this ATM switch 101. Main control unit (C
C) 102 and a main memory (MM) 103 that holds software for the main controller 102 and the like.

As a result, in the above-mentioned ATM switching network, for example, ATM cells transmitted from a terminal or the like accommodated in the interface device 201 are input to the ATM switching device 100 through the interface device 201 and the concentrator 301, and the ATM switching device At 100, an ATM switch 101 is provided according to the header added to this ATM cell.
Automatically selects the cell transfer path, and the concentrator 3
02, the interface device 202 (or the concentrator 30)
3, the ATM cell is sent to the transfer destination terminal or the like through the interface device 203).

In the above-mentioned ATM switching network, for example, when a failure occurs in the ATM layer (cell multiplexing / switching layer) up to the interface device 201, the fact is detected by the interface device 201, and FIG.
As indicated by the dotted line therein, this interface device 201
From each interface device 202, by transmitting an AIS (Alarm Indication Signal) cell of VP (Virtual Path) / VC (Virtual Channel) from the ATM to the downstream direction of the ATM cell (direction of the ATM switch 101).
The rear station on the 203 side is notified that a failure has occurred.

When the failure is recovered, the transmission of the AIS cell from the corresponding interface device 201 is stopped, and the failure recovery is similarly notified to the succeeding station.

[0009]

However, in the above-mentioned ATM switching network, when a failure occurs in the ATM layer (cell multiplexing / switching layer), the fact can be notified to the succeeding station. When a failure occurs in the line layer or the switching switch unit (ATM switch 101), the failure notification method to the succeeding station as described above is not established at this time, so that the failure is detected in the succeeding station. There is a problem that you cannot do it.

Further, even when the failure of the ATM layer is notified to the succeeding station, the apparatus which detects the failure of the ATM layer and sends out the AIS cell (for example, the interface device 20).
When some abnormality such as a device failure occurs in 1), it becomes impossible to send an AIS cell, and it becomes impossible to normally notify the subsequent station of failure occurrence and failure recovery. There is also.

Further, normally, in the ATM switching network, a charging counter (cell counter) for charging is provided on each of the interface devices 201 to 203, but the line layer, the ATM layer, and the interface devices 201 to 20 are provided.
3. When a failure occurs in the ATM switch 101 or the like, the number of input / output cells for the billing counter on each of the interface devices 201 to 203 is different, which makes it impossible to perform accurate cell billing. There is also.

The present invention was devised in view of the above problems, and even if a failure occurs in any of the line layer, the cell multiplexing / switching layer, the interface device, and the switching switch unit, other interface devices, etc. A method for coping with a failure in a fixed-length cell switch and an interface equipped with a fixed-length cell switch, which not only notifies the succeeding station of the failure but also stops the charging counter to enable normal charging. An object of the present invention is to provide a device, a line concentrator equipped with a fixed length cell switch, and a fixed length cell switch.

[0013]

FIG. 1 is a block diagram of the principle of the present invention. In FIG. 1, reference numeral 1 is a fixed-length cell switch for handling fixed-length cells, which is an exchange switch unit 2 and an exchange switch unit 2. It is configured to include an interface unit (interface device) 3 attached to an input / output unit, and the interface unit 3 further includes a billing counter 3
1, an alarm cell detection unit 32 and a billing counter control unit 33. Reference numeral 4 is a main control unit for the exchange switch unit 2.

Here, the alarm cell detection unit 32 detects an alarm cell issued when a failure occurs in the cell multiplexing / switching layer that handles cell multiplexing and switching, and the charging counter control unit 33 detects this alarm cell. When the alarm cell is detected by the unit 32, the counting of the billing counter 31 for the corresponding connection is stopped (claim 3).

The charging counter control unit 33 described above is
When the alarm cell detection unit 32 detects that the alarm cell transmission is stopped, the charging counter 31 for the corresponding connection is detected.
Is restarted (claim 4). With such a configuration, in the fixed-length cell switch 1 described above, when the interface unit 3 receives an alarm cell issued when a failure occurs in the cell multiplexing / switching layer, the interface unit 3 causes the alarm cell detection unit 32 to detect the alarm cell. When the alarm cell is detected, the billing counter control unit 33 stops the counting of the billing counter 31 for the corresponding connection (claim 1).

Then, when the interface unit 3 detects that the alarm cell transmission is stopped, the interface unit 3 causes the accounting counter control unit 33 to restart the counting of the accounting counter 31 for the corresponding connection (claim 2). Next, FIG. 2 is also a block diagram of the principle of the present invention. In FIG. 2 as well, 1 is a fixed-length cell switch that handles fixed-length cells, and is an exchange switch unit 2 and this exchange switch unit 2.
The interface unit 3 is equipped with an interface unit (interface device) 3 attached to the input / output unit of the device. In this case, the interface unit 3 includes a charging counter 31, a far-end reception failure cell detection unit 34, and a charging counter control unit 35. Is configured. In this case also, 4 is a main control unit for the exchange switch unit 2.

Here, the far-end reception failure cell detection unit 34 is
When a failure occurs in the cell multiplexing / switching layer that handles cell multiplexing and switching, the far-end reception failure cell emitted from the terminating device (such as a subscriber terminal) in the cell multiplexing / switching layer is detected. When the far-end reception faulty cell detection unit 34 detects a far-end reception faulty cell, the billing counter 31 stops counting the corresponding connection (claim 7).

The charging counter control unit 35 described above is
When the far-end reception defective cell detection unit 34 detects that the transmission of the far-end reception defective cell is stopped, the accounting counter 31 for the corresponding connection is restarted (claim 8). With such a configuration, in the fixed-length cell switch 1 described above, when the cell multiplexing / switching layer fails, the far-end reception failure cell issued from the terminating device (such as a subscriber terminal) of the cell multiplexing / switching layer is the interface unit 3 When this is received, the far-end reception failure cell is detected by the far-end reception failure cell detection unit 34, and the charging counter control unit 35
By this, the counting of the billing counter 31 for the corresponding connection is stopped (claim 5).

When the far-end reception failure cell detection unit 34 detects that the far-end reception failure cell transmission is stopped, the interface unit 3 causes the charge counter control unit 35 to count the charge counter 31 for the corresponding connection. It is restarted (claim 8). Next, FIG. 3 is also a block diagram of the principle of the present invention. In FIG. 3 as well, 1 is a fixed-length cell switch that handles fixed-length cells. In this case, the exchange switch unit 2 and the exchange switch unit 2 are used. Main control unit 4 of
The exchange switch unit 2 is configured to include a plurality of interface units (interface devices) 3 attached to the input / output units, and the interface unit 3 further includes a billing counter 31, an identification information storage unit 36, an identification information receiving unit 37, It comprises a path detector 38, an alarm cell transmitter 39, and a charge counter controller 40.

Here, the identification information storage section 36 stores unique identification information about the opposite device, and the identification information receiving section 37 is provided from the main control section 4 for the exchange switch section 2 to the failure interface section. 3 is received, and the path detection unit 38 receives the notification of the unique identification information about the failure interface unit 3 from the identification information receiving unit 37, the identification information storage unit. 36 to detect a path that matches the notified unique identification information.

The alarm cell sending unit 39 sends an alarm cell to the path detected by the path detecting unit 38, and the billing counter control unit 40 is detected by the path detecting unit 38. The counting of the billing counter 31 is stopped for the pass (claim 13). In addition,
At this time, when the alarm cell sending unit 39 receives a notification from the main control unit 4 that the failure in the failure interface unit 3 has been recovered, it stops sending the alarm cell.
The billing counter control unit 40 restarts the counting of the billing counter 31 when the alarm cell sending unit 39 stops sending the alarm cell (claim 14).

With such a configuration, in the fixed-length cell switch 1 described above, when a path is connected to each interface unit 3, unique identification information about the opposite device is added to the path information, and the identification information is added. The path is set in advance by storing it in the storage unit 36, and each interface unit 3
If a failure occurs in a certain interface unit 3 of the
The main control unit 4 notifies the interface units 3 other than the fault interface unit 3 of unique identification information about the fault interface unit 3.

Then, in the interface section 3 which has received the notification of the unique identification information of the fault interface section 3 at the identification information receiving section 37, the path detecting section 38 searches the identification information storing section 36 to notify it. A path that matches the generated unique identification information is detected, and the alarm cell transmission unit 3
An alarm cell is sent from 9 to the path detected by the path detection unit 38 (claim 9).

Further, when the failure in the failed interface section 3 is recovered, the main control section 4 notifies the interface sections 3 other than the failed interface section 3 to that effect, and the interface section 3 that has received this notification. The transmission of the alarm cell from the alarm cell transmitter 39 is stopped (claim 10). In the interface unit 3 which has received the notification of the unique identification information about the fault interface unit 3 at the identification information receiving unit 37, as described above, for the path that matches the notified unique identification information, , The alarm cell is transmitted, and the charging counter control unit 40 stops the counting of the charging counter 31 (claim 11).

When the fault in the fault interface unit 3 is recovered, the main control unit 4 notifies the interface units 3 other than the fault interface unit 3 to that effect, and the interface unit 3 receiving this notice The transmission of the alarm cell is stopped and the counting of the charging counter 31 is restarted by the charging counter control unit 40.
2).

Next, FIG. 4 is a block diagram of the principle of the present invention.
Also in FIG. 4, reference numeral 1 denotes a fixed-length cell switch that handles fixed-length cells, and in this case as well, an exchange switch unit 2, a main control unit 4 for this exchange switch unit 2, and input / output of the exchange switch unit 2. The interface device 3 is provided with a plurality of interface parts (interface devices) 3 attached to the parts. As shown in FIG.
The charging counter 31, the routing information storage unit 41, the routing information receiving unit 42, the path detecting unit 43, the alarm cell transmitting unit 44, and the charging counter control unit 45 are provided.

Here, the routing information storage unit 41 stores the routing information, and the routing information receiving unit 42 receives the routing information about the fault interface unit 3 from the main control unit 4 for the exchange switch unit 2. When the routing information receiving unit 42 receives the notification of the routing information about the failure interface unit 3, the path detecting unit 43 searches the routing information storage unit 41 and notifies the routing information. The path that matches the information is detected.

The alarm cell sending unit 44 sends an alarm cell to the path detected by the path detecting unit 43, and the billing counter control unit 45 detects the path detecting unit 43. The counting of the billing counter 31 is stopped for the pass (claim 19). In addition,
Also in this case, when the alarm cell sending unit 44 receives a notification from the main control unit 4 that the failure in the failure interface unit 3 has been recovered, the alarm cell sending unit 44 stops sending the alarm cell, and the charging counter control is performed. The unit 45 restarts the counting of the billing counter 31 when the sending of the alarm cell by the alarm cell sending unit 44 is stopped (claim 2).
0).

With such a configuration, in the fixed-length cell switch 1 described above, when a failure occurs in a certain interface section 3 of the plurality of interface sections 3, the main control section 4 causes the interfaces other than the failed interface section 3 to operate. Part 3
Is notified of the routing information about the fault interface unit 3. Then, this failure interface unit 3
In the interface unit 3 that has received the notification of the routing information regarding the above, the path detection unit 43 detects a path that matches the notified routing information, and the alarm cell transmission unit 44
From this, an alarm cell is sent to the path detected by the path detection unit 43 (claim 15).

Further, when the failure in the failed interface section 3 is recovered, the main control section 4 notifies the interface sections 3 other than the failed interface section 3 to that effect, and the interface section 3 receiving this notification The output of the alarm cell from the alarm cell transmitter 44 is stopped (claim 1
6). In this case as well, in the interface unit 3 that has received the notification of the routing information about the fault interface unit 3 at the routing information receiving unit 42, as described above, for the path that matches the notified routing information. , The alarm cell is transmitted, and the charging counter control unit 45 stops the counting of the charging counter 31 (claim 17).

When the fault in the fault interface unit 3 is recovered, the main control unit 4 notifies the interface units 3 other than the fault interface unit 3 to that effect, and the interface unit 3 receiving this notice The transmission of the alarm cell from the alarm cell transmission unit 44 is stopped and the charging counter control unit 45 restarts the counting of the charging counter 31 (claim 18).

Next, FIG. 5 is a block diagram of the principle of the present invention.
In FIG. 5, reference numeral 1 is a fixed-length cell switch that handles fixed-length cells, and is attached to an exchange switch unit 2, a main control unit 4 for this exchange switch unit 2, and an input / output unit of the exchange switch unit 2. The interface unit (interface device) 3 and a concentrator (concentrator) 5 for concentrating the input / output information of each interface unit 3 are provided, and the concentrator 5 includes a failure detection unit 51, It comprises a connection information storage unit 52, a connection information extraction unit 53, and an alarm cell transmission unit 54.

Here, the failure detection unit 51 is for detecting the occurrence of a failure in the interface unit 3, and the connection information storage unit 52 is for storing the connection information connected to the interface unit 3. is there.
Further, the connection information extraction unit 53 is provided with the failure detection unit 51.
When it is detected that a failure has occurred in the interface section 3, the connection information stored in the connection information storage section 52 is searched to find the failure interface section 3
All the connection information connected to the alarm cell are extracted, and the alarm cell transmission unit 54 transmits the alarm cells to all the connections extracted by the connection information extraction unit 53 (claim 25). .

When the alarm cell transmission unit 54 receives the notification that the failure of the interface unit 3 has been recovered,
The transmission of the alarm cell is stopped (claim 2).
6). With such a configuration, in the fixed length cell switch 1 described above, when the failure detecting section 51 detects that a failure has occurred in the interface section 3 in the concentrating section 5, the connection information extracting section 53 causes the connection information storage section to store the connection information. The connection information stored in the section 52 is searched to extract all the connection information connected to the failure interface section 3, and the alarm cell transmission section 54 extracts all the connections extracted by the connection information extraction section 53. An alarm cell is sent to
1).

When the fault in the fault interface unit 3 is recovered, the main control unit 4 notifies the interface units 3 other than the fault interface unit 3 to that effect, and the line concentrating unit 5 that has received this notice The output of the alarm cell from the alarm cell transmitter 54 is stopped (claim 22). Further, when it is detected in the concentrator 5 that a failure has occurred in the interface unit 3, as described above, the concentrator 5 (alarm cell transmitter 54) transmits an alarm cell to all connections. However, at this time, the failure interface unit 3
At, the billing counter stops counting (claim 23).

When the fault in the fault interface unit 3 is recovered, the main control unit 4 notifies the interface units 3 other than the fault interface unit 3 to that effect, and the line concentrating unit 5 that has received this notice The transmission of the alarm cell from the alarm cell transmission unit 54 is stopped, and the counting of the charging counter is restarted in the interface unit 3 where the failure is recovered (claim 24).

Next, FIG. 6 is a block diagram of the principle of the present invention.
Also in FIG. 6, reference numeral 1 denotes a fixed-length cell switch that handles fixed-length cells, and is attached to the exchange switch unit 2, the main control unit 4 for the exchange switch unit 2, and the input / output unit of the exchange switch unit 2. The interface unit 3 includes a plurality of interface units (interface devices) 3, and the interface unit 3 controls the charging counter 31, the activated cell transmission unit 46, the activated cell monitoring unit 47, the alarm cell transmission unit 48, and the charging counter control. It is provided with a section 49. Reference numeral 4 is a main control unit for the exchange switch unit 2.

Here, the activated cell sending section 46 sends the activated cell to the other interface section 3 at a predetermined cycle through a dedicated permanent connection section provided between the other interface sections 3. The activation cell monitoring unit 4
Reference numeral 7 monitors the activated cells from the interface units 3 other than itself, and the alarm cell transmission unit 48 causes the activated cell monitoring unit 47 not to reach the activated cells at a predetermined interval. Is detected, an alarm cell is sent to all the connected paths, and the charging counter controller 49 causes the activated cell monitor 47 to reach the activated cell at a predetermined interval. When it is detected that it is not, the counting of the billing counter 31 is stopped (claim 31).

The alarm cell sending unit 48 sends an alarm when the activated cell monitoring unit 47 detects that the activated cells arrive again at a predetermined interval after sending the alarm cell. The transmission of cells is stopped, and the charging counter control unit 49 thus makes the alarm cell transmission unit 48
When the transmission of the alarm cell in the is stopped, the charging counter 31
Counting is restarted (claim 3
2).

With such a configuration, in the fixed length cell switch 1 described above, in the interface section 3, the activated cell is sent from the activated cell sending section 46 to the other interface section 3 at a predetermined cycle. The activated cell monitoring unit 47 monitors activated cells from the interface units 3 other than itself. When the activated cell monitoring unit 47 detects that the activated cells do not arrive at a predetermined interval, the alarm cell transmission unit 48 transmits the alarm cells to all the connected paths. At the same time, the charge counter controller 49 controls the charge counter 3
The count of 1 is stopped.

That is, in the fixed length cell exchange 1 shown in FIG. 6, each interface section 3 activates cells at a predetermined cycle through a dedicated permanent connection section provided between the interface sections 3. In addition to notifying the other interface units 3, in each interface unit 3, the activated cells from the interface units 3 other than itself are monitored by the activated cell monitoring unit 47, and the activated cells arrive at a predetermined interval. If not, the alarm cell is transmitted from the alarm cell transmitter 46 to all the connected paths (claim 27).

When it is detected that the activated cells have arrived at a predetermined interval after the alarm cell is transmitted, the activated cell transmitter 46 stops transmitting the alarm cell (claim). 28). Also, the interface unit 3 other than yourself
If the activated cells from the cell do not arrive at a predetermined interval, the alarm cells are sent to all the connected paths as described above, but at this time, the billing counter control unit 4 simultaneously.
The billing counter 31 stops counting by 9 (claim 29).

After the alarm cells are transmitted as described above, if it is detected that the activated cells have arrived at a predetermined interval, the activation cell transmitter 46 stops transmitting the alarm cells. At the same time, the billing counter control section 49 restarts the counting of the billing counter 31 (claim 30). Next, FIG. 7 is also a block diagram of the principle of the present invention. In FIG. 7 as well, 1 is a fixed-length cell switch for handling fixed-length cells.
Main control unit 4 for communication, a plurality of interface units (interface devices) 3 attached to the input / output units of the exchange switch unit 2, and a concentrator unit (concentrator device) 5 for concentrating the input / output information of each interface unit 3. In addition, the line concentrating unit 5 is configured to include a dedicated cell supplementing unit 55 and a cell conversion copying unit 56.

Here, the dedicated cell capturing unit 55 captures the own-station dedicated cell having the identification information or the routing information unique to the interface unit from the interface unit 3, and the cell conversion copying unit 56 uses this dedicated cell. Cell capturing unit 55
When the own-station-dedicated cell is captured, all routing information is added to the own-station-dedicated cell, and a plurality of own-station-dedicated cells having the same contents are copied.

As a result, in the fixed length cell switch 1 described above, in the concentrator 5, the own cell dedicated cell having the identification information unique to the interface section or the routing information from the interface section 3 is captured by the dedicated cell capturing section 55. Then, the cell converting / copying unit 56 adds all the routing information to the own-station-dedicated cell, and further copies a plurality of own-station-dedicated cells having the same contents. Then, it is possible to automatically identify and specify the interface unit 3 which has transmitted the own-station dedicated cell (claim 33).

Next, FIG. 8 is a block diagram of the principle of the present invention.
In FIG. 8 as well, 1 is a fixed-length cell switch that handles fixed-length cells. In this case, three or more switch stages 21 are provided.
The replacement switch unit 2 having -1 to 21-N (where N is a natural number of 3 or more), the main control unit 4 for the replacement switch unit 2, and the input / output unit of the replacement switch unit 2 are attached. It is configured to include a plurality of interface units 3.

In the fixed length cell exchange 1 of the present invention applied to the fixed length cell exchange 1 as shown in FIG. 8, the intermediate switch stage 21-2 in the exchange switch section 2 is used in the method of coping with a failure. 21- (N-1), a failure occurs in any of the intermediate switch stages 21-2 to 21- (N) for all the interface units 3 accommodated in the main control unit 4. -1) is notified of the routing information, and the interface unit 3 that has received the notification of the routing information sends an alarm cell to a path that matches the notified routing information (claim 34).

When the failure of the intermediate switch stages 21-2 to 21- (N-1) in the exchange switch section 2 is recovered, the fact is notified to all the interface sections 3 accommodated in the main control section 4. Is notified, and the interface unit 3 that has received this notification stops sending the alarm cell (claim 35). In the interface unit 3 that has received the notification of the routing information about the intermediate switch stages 21-2 to 21- (N-1) in the exchange switch unit 2, as described above, the path that matches the notified routing information. A warning cell is sent to the client, but at this time, the counting of the charging counter is stopped at the same time (claim 36).

When the failure of the intermediate switch stages 21-2 to 21- (N-1) in the exchange switch unit 2 is recovered, the fact is notified to all the interface units 3 accommodated in the main control unit 4. Is notified, and the interface unit 3 that has received this notification stops the transmission of the alarm cell, but at the same time, the counting of the charging counter is restarted (claim 37).

Next, FIG. 9 is a block diagram of the principle of the present invention.
In FIG. 9 as well, reference numeral 1 denotes a fixed-length cell switch that handles fixed-length cells, and is attached to the exchange switch unit 2, the main control unit 4 for the exchange switch unit 2, and the input / output unit of the exchange switch unit 2. A plurality of interface units (interface devices) 3 and a concentrator (concentrator) 5 for concentrating the input / output information of each interface unit 3. Further, the concentrator 5 includes interface failure detectors 57. The interface unit 3 includes an alarm cell information receiving unit 59 and a pseudo alarm cell creating unit 60.

Here, in the concentrator 5, the interface fault detector 57 detects that a fault has occurred in the interface 3, and the alarm cell information transmitter 58 has the interface fault detector 57. When a failure of the interface unit 3 is detected by, the cell to which the information indicating the alarm cell is added is sent to the exchange switch unit 2.

On the other hand, in the interface section 3, the alarm cell information receiving section 59 receives a cell provided with the information indicating that the alarm cell is the above alarm cell. When the information receiving unit 59 receives a cell provided with information indicating that it is an alarm cell, it creates a pseudo alarm cell and sends it to the line side.

The interface section 3 has a charging counter, and when the alarm cell information receiving section 59 receives a cell to which the information indicating that the alarm cell is added, the interface section 3 stops the counting of this charging counter. A counter control unit may be provided (claim 4).
1). With such a configuration, in the fixed-length cell switch 1 described above, when the interface unit failure detection unit 57 detects that a failure has occurred in the interface unit 3 in the line collection unit 5, the line collection unit 5 (alarm cell information From the sending unit 58), the cell to which the information indicating that it is an alarm cell is attached is sent to the exchange switch unit 21, and then the cell to which the information indicating that it is this alarm cell is attached is an alarm of another interface unit 3. When received by the cell information receiving unit 59, in the other interface unit 3, the pseudo alarm cell creating unit 60 creates a pseudo alarm cell and sends it to the line side (claim 38).

As described above, when the cell to which the information indicating the alarm cell is added is received by the other interface section 3, the pseudo alarm cell creation section 60 of the other interface section 3 causes the pseudo alarm cell to be generated. Is generated and sent to the line side, but at this time, the counting of the charging counter can be stopped by the above-mentioned charging counter control unit (claim 39).

Next, FIG. 10 is also a block diagram of the principle of the present invention. In FIG. 10 as well, 1 is a fixed-length cell switch that handles fixed-length cells, and is an exchange switch unit 2 and input / output of this exchange switch unit 2. And a plurality of interface units (interface devices) 3 attached to the unit, and the interface unit 3 further includes a billing counter 3
1, a line layer failure detection section 61 and a charging counter control section 62. Reference numeral 4 is a main control unit for the exchange switch unit 2.

Here, the line layer failure detection section 61 detects a failure in the line layer, and the billing counter control section 62 detects that the line layer failure detection section 61 detects a failure in the line layer. The billing counter 31 stops counting for all connections (claim 44). The above-mentioned charging counter control unit 62
When the line layer failure detection unit 61 detects the recovery of the failed line layer, the accounting counter 31 restarts counting (claim 45).

With such a configuration, in the fixed length cell switch 2 described above, a failure of the line layer occurs in the interface unit 3.
When it is detected by the line layer failure detection unit 61, the charging counter control unit 62 of the interface unit 3 stops counting the charging counters 31 for all the connections (claim 42). Then, when the recovery of the failed line layer is detected by the line layer failure detection unit 61 of the interface unit 3, in the interface unit 3, the charging counter control unit 62 restarts the counting of the charging counters 31 for all the connections. (Claim 43).

[0058]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. (A) Description of First Embodiment FIG. 11 is a block diagram showing a configuration of an ATM exchange as a first embodiment of the present invention. As shown in FIG.
The TM switch 11 includes an ATM switch 12, a main controller (C
C) 13, a main memory unit 14, a plurality of interface devices (interface units) 15 such as UNI and NNI attached to the input / output unit of the ATM switch 11, and a plurality of line concentrators for collecting the input / output information of these interface devices 15. It is configured with a section (concentrator) 16. Reference numeral 17 is a terminating device such as a subscriber terminal accommodated in each interface device 15 via a line.

Here, the ATM switch (exchange switch section) 12 automatically determines the transfer route of the cell according to the tag information (routing information such as the transfer destination address) set in the header of the input ATM cell. In this embodiment, a switch called a multi-stage self-routing (MSSR) type switch as shown in FIG. 12 is used, and a plurality of switching elements 12 are used.
A-1 to 12A-N, 12B-1 to 12B-N, 12C
It is configured to have three switch stages 12A to 12C using -1 to 12C-N (N is a natural number).

Then, each switching element 12A-1.about.
12A-N, 12B-1 to 12B-N, 12C-1 to 1
2C-N switches the output path of the data (cell) according to "1" or "0" of the input data. These 12A-1 to 12A-N, 12B-1 to 12B-N, 1
In 2C-1 to 12C-N, the tag information set in a binary number in the header of the input cell is sequentially read for each bit, and the alternative of "1" or "0" is repeated. As a result, the cell transfer route is automatically selected.

However, in the present embodiment, as will be described later, when a failure occurs in the intermediate switch stage 12B of the present ATM switch 12, the tag information about the switch stage 12B is notified to each interface device 15, so that the intermediate device The tag information about the (second) switch stage 12B is
A link is set between the first switch stage 12A and the second switch stage 12B so as to coincide with the row number of the intermediate switch stage 12B.

Next, the main control section (CC) 13 described above is used in the ATM switch 1 including the ATM switch 12 described above.
The main memory 14 stores software for the main controller 13 and the like. Further, each interface device 15 has a line layer,
When some trouble occurs in the ATM layer that handles cell multiplexing and switching, the interface device 15 other than itself, or the ATM switch 12, an AIS cell (alarm cell)
Is generated, and the charging for the cell passing through the corresponding connection is stopped.

Each concentrator 16 normally adds tag information for instructing the transfer path of the input cell to the input cell, but in the present embodiment, each concentrator 16 of each interface device 15 is provided. When a failure occurs in one of the interface devices 15, it can be detected and the AIS cell can be sent from the concentrator 16 to all the connections.

FIG. 13 is a block diagram showing the configurations of the interface device 15 and the concentrator 16 described above.
As shown in FIG. 3, the interface device 15 includes a line layer fault monitor 15-1, an ATM layer fault monitor / AIS cell generator 15-2, an AIS cell monitor 15-3, and an AIS.
Cell control unit 15-4, connection data storage unit 15-
5, two cell counters 15-6 on the ATM switch 12 side and the terminating device 17 side, a cell counter control unit 15-7, a microprocessor (μP) 15-8, and a buffer 15-
9, the concentrator 16 includes an interface device failure monitor 16-1, a connection data storage 16-2, and a microprocessor (μP) 16-.
3, AIS cell image creation unit 16-4 and virtual channel connection (VCC) table 16-5.

Here, first, in the interface device 15, a line layer fault monitoring unit (line layer fault detection unit)
Reference numeral 15-1 is for detecting a fault in the accommodated line layer, and the ATM layer fault monitoring / AIS generation unit 15 is provided.
-2 monitors (detects) a failure in the ATM layer that handles multiplexing and switching of ATM cells, and when the failure occurrence is detected, the fact is notified to the succeeding station (interface device 15, concentrator) to which the cell is transferred. 16, an AIS cell (alarm cell) for notifying the terminating device 17), and a virtual path (VP: Virtual Path) / a virtual channel (VC: Virtual Channel) on the corresponding line. It is sent to the connection (VPC / VCC).

Further, the AIS cell monitoring section (alarm cell detection section) 15-3 detects the occurrence of a failure in the line layer in the line layer failure monitoring section 15-1, or the ATM layer failure monitoring / The AIS generation unit 15-2 detects an AIS cell received when a failure has occurred in the ATM layer, and the AIS cell control unit (alarm cell transmission unit) 15-4 will be described later. As described above, the connection (V
The AIS cell is transmitted to PC / VCC).

The AIS cell controller 15-4 is
Upon receiving a notification from the main control unit 4 for the ATM switch 12 that the failure in the failure interface device 15 has been recovered, the transmission of the AIS cell is stopped. Next, the connection data storage unit (identification information storage unit, routing information storage unit) 15-5 is provided with a unique ID (OEid), tag information or ATM switch 1 for the opposite device.
Various connection data such as tag information for the intermediate switch stage 12B (each switching element 12B-1 to 12B-N) in 2 is stored. The connection data includes, for example, as shown in FIG. 14, tag information (TAG) and cell output side V for each virtual path identifier (VPI) / virtual channel identifier (VCI).
PI / VCI, identification I unique to the interface device 15
It has a format in which D (OEid) and the like are stored.

Further, the microprocessor (identification information receiving section, routing information receiving section, path detecting section) 15-8 is
Here, when the OE identification information or routing information about the failed interface device 15 is received from the main control unit 13, the connection data storage unit 15-5.
To detect a path that matches the received OEid or tag information for the fault interface device 15.

Further, each cell counter (billing counter)
The numeral 15-6 counts the number of cells sent to the ATM switch 12 side and the terminating device 17 side, respectively, and obtains charging information for charging an amount corresponding to the number as a line usage fee or the like. The cell counter control unit (billing counter control unit) 15-7 stops the count of the cell counter 15-6 in the following cases.

(1) When the line layer failure monitoring unit 15-1 detects that a failure has occurred in the line layer. (2) When the ATM layer failure monitoring unit 15-2 detects that a failure has occurred in the ATM layer. (3) When the AIS cell is detected by the AIS cell monitoring unit 15-3. In the case of (1) above, all connections (VPC
/ VCC), in the cases of (2) and (3) above, the cell counter 15-6 stops counting for the corresponding connection (VPC / VCC).

Further, this cell counter control section 15-7
The cell counter 15-6 restarts counting in the following cases. (1) When the restoration of the faulty line layer is detected by the line layer fault monitoring unit 15-1. (2) When the AIS cell monitoring unit 15-3 detects the stop of the AIS cell transmission.

(3) A from the AIS cell controller 15-4
When the transmission of IS cells is stopped. The buffer 15-9 temporarily holds an input cell, and in this case, the cell input through the AIS cell monitoring unit 15-3 during normal operation and the AI at the time of a failure occur.
The AIS cell generated by the S cell control unit 15-4 and the AIS cell are selectively transmitted to the line side in the normal time / when a failure occurs.

Next, in the concentrator 16, the interface device failure monitoring section (fault detection section) 16-1 detects that a failure has occurred in the interface apparatus 15, and the connection data storage section 16-2 , The connection data connected to the interface device 15 is stored in the same format as that shown in FIG.

Further, the microprocessor (connection information extraction unit) 16-3 is the interface device failure monitoring unit 16-1 in the interface device 1 here.
When it is detected that a failure has occurred in 5, the connection data stored in the connection data storage unit 16-2 is searched to extract all the connection data connected to the failure interface device 15. Yes, AIS cell image creation unit (alarm cell transmission unit) 16
-4 writes a predetermined bit image in the payload type identifiers (PTIs) and payload portions of all the cells to be input, and inputs the bit image into the VCC table 16-5, so that the microprocessor 16-3 as the connection information extracting unit. All extracted connections (VPC / V
CC), an AIS cell is transmitted.

The AIS cell image creating unit 16
-4, when receiving a notification from the main control unit 13 that the failure in the failure interface device 15 has been recovered, it stops sending the AIS cell. Hereinafter, a method of coping with a failure in the ATM exchange 11 configured as described above will be described in detail.

(A1) When Failure Occurs in ATM Layer First, in the ATM switch 11, when a failure occurs in the ATM layer that handles multiplexing and switching of ATM cells, normally, the interface device 15 that has detected this failure is followed by Although the AIS cell is sent to the unit side (ATM switch side), in the interface device 15 having the cell counter 15-6 that receives this AIS cell, the AIS cell monitoring unit 15-3 causes the VPI / The VCI is detected, and this is notified to the cell counter control unit 15-7.

Then, the cell counter controller 15-7
Connection (V that corresponds to the notified VPI / VPI
Stop the counting of each cell counter for PC / VCC). Then, after that, the failure of the ATM layer is recovered and the transmission of the AIS cell is stopped.
When it is detected by the interface device 15,
The cell counter control unit 15-7 restarts the counting of the cell counter 15-6 for the connection (VPC / VCC) stopped as described above.

As described above, according to the ATM switch 11 of this embodiment, the A issued when the ATM layer fails.
When the interface device 15 receives the IS cell, the interface device 15 receives a cell counter control unit 15 from the interface device 15.
By -7, until the failure is recovered and AIS cell transmission is stopped, the corresponding connection (VPC / VC
Since the counting of the cell counter 15-6 for C) is stopped, unnecessary billing at the time of failure can be reliably prevented, and accurate billing can always be performed.

(A2) When a failure occurs in the line layer Next, a method of coping with the occurrence of a failure in the line layer of the above-mentioned ATM switch 11 will be described below. For example, an interface device 1
When a failure occurs in the line layer between the 5 and the terminating device 17, the interface device 15 that accommodates the line,
The line layer failure monitoring unit 15-1 detects the occurrence of this failure, and the line layer failure monitoring unit 15-1 receives it and informs the ATM layer failure monitoring / AIS generation unit 15-2.
The AIS cell transmission request is transmitted by specifying all connections (all VPC / VCC), and the cell counter 15-6
To all cell charging stop instruction.

Then, the ATM layer fault monitor / AIS generator 15-2 generates an AIS cell for VP / VC and applies this to all connections (VCC / VPC) virtually accommodated in the fault line. For ATM switch 12
The cell counter control unit 15-7 stops the counting of the cell counter 15-6 for all the connections (VPC / VCC).

In the other interface device 15 which has received the AIS cell sent from the ATM layer fault monitor / AIS generator 15-2 as described above, as described in item (1), the AIS cell monitor is used. AIS at 15-3
Since the cell is detected, similarly, the cell counter control unit 1
The cell counter 15-6 for all connections (VPC / VCC) in the interface device 15 is stopped by 5-7.

That is, in the ATM switch 11 of this embodiment, when a failure occurs in the line layer, the counting of all the cell counters 15-6 is stopped. Then, after that, the restoration of the faulty line layer is performed by the line layer fault monitoring unit 15 of the interface device 15.
When it is detected by -1, in response to this, the transmission of the AIS cell from the ATM layer fault monitoring / AIS generation unit 15-2 is stopped and the cell counter control unit 15-7.
As a result, the counting of the cell counter 15-6 for all the connections (VPC / VCC) that have been stopped as described above is restarted.

As described above, according to the ATM switch 11 (interface device 15) of this embodiment, when the interface device 15 detects a failure in the line layer, the interface device 15 recovers the failure in the line layer. , All connections (VPC / VC
Since the counting of the cell counter 15-6 for C) is stopped, in this case as well, unnecessary billing at the time of failure can be reliably prevented, and accurate billing can always be performed.

(A3) Failure of Interface Device 15 Next, FIGS. 15 and 16 show a method of coping with a failure of the ATM switch 11 when a failure of the interface device 15 occurs. This will be described with reference to the flowchart (steps S1 to S12). First, A
A person who maintains the TM switch 11 or the like uniquely identifies identification information (OEi
d) is given. Then, each interface device 1
When connecting a path between 5 (when setting VCC),
The main control unit 13 determines the path information (input VPI / V
CI, output VPI / VCI, tag information, etc.) and OEid of the interface device 15 on the path, or tag information (TAG) indicating a transfer route to the opposite interface device 15.

The interface device 15 receiving this notification
As shown in FIG. 14, the notified OEid, TAG
Stored in a predetermined area of the connection data and stored in the connection data storage unit 15-5,
The path is set by adding the OEid for the opposite device to the path information. After that, when some failure occurs in a certain interface device 15 among the interface devices 15, the main control unit 13 causes the interface devices 15 other than the failed interface device 15 to receive the OEid for the failed interface device 15. Or TAG
Notify.

Further, as shown in FIG. 15, when the interface device 15 receives this notification at the microprocessor 15-8 as the identification information receiving section (step S).
1) In the interface device 15, the microprocessor 15-8, which also functions as a path detector, searches the connection data stored in the connection data storage 15-5 (step S2),
The connection data corresponding to the OEid or TAG notified from the main control unit 13 is extracted, and the OEid or TA is extracted.
A path matching G is detected (step S3).

Then, the microprocessor 15-8 is
Applicable connection (cell output VPC / VCC)
The output side VPI / VCI is controlled by the AIS cell control so that both the transmission / reception cell counters 15-6 having the VPI / VCI The unit 15-4 and the cell counter control unit 15-7 are notified (step S
4, S5).

The microprocessor 15-8 determines whether or not all connection data has been searched in the connection data storage unit 15-5 (step S6), and if all connection data have not been searched (step S6). If NO in step S6), the same processing as steps S2 to S5 described above is repeated until all connection data are searched, while if all connection data have been searched (step S6 is determined to be YES). The microprocessor 15
The process at -8 ends.

After that, in the AIS cell control section 15-4,
For the connection detected by the microprocessor 15-8 as described above, the AIS cell is sent to the line side to notify the opposite device side that a failure has occurred, and the cell counter control unit 15-7 Similarly, the count of the cell counter 15-6 corresponding to the connection detected by the microprocessor 15-8 is stopped.

When the failure in the failed interface device 15 is recovered, the main control unit 13 notifies the interface devices 15 other than the failed interface device 15 to that effect by OEid or TAG, as shown in FIG. When the interface device 15 receives this notification (step S7), the microprocessor 15-8 of the interface device 15 similarly retrieves the connection data stored in the connection data storage unit 15-5. Then, the connection data corresponding to the OEid or TAG notified from the main control unit 13 is extracted, and the path matching the OEid or TAG is detected (step S9).

Then, the microprocessor 15-8 is
VP of the corresponding connection (output side VPC / VCC)
Both cell counters 15 for transmission / reception having I / VCI
In order to restart the count of -6 and stop the transmission of the AIS cell from the AIS cell control unit 15-4,
The output VPI / VCI is notified to the AIS cell control unit 15-4 and the cell counter control unit 15-7 (step S).
10, S11).

The microprocessor 15-8 determines whether or not all the connection data has been searched in the connection data storage unit 15-5 (step S12), and when all the connection data have not been searched (step S12). If NO is determined in)
Repeats the same processing as steps S7 to S11 described above until all connection data are searched,
If all the connection data have been searched (YES in step S12), the processing by the microprocessor 15-8 ends.

As a result, the transmission of the AIS cell from the AIS cell control unit 15-4 is stopped and the cell counter control unit 15-7 restarts the counting of the cell counter 15-6. Thus, the AT in the present embodiment
According to the M switch 11 (interface device 15), when a failure occurs in a certain interface device 15 among the interface devices 15, unique identification information (OEid) or tag information (OEid) of the failed interface device 15 is generated. The AIS cell is transmitted from the interface devices 15 other than the faulty interface device 15 until the fault in the faulty interface device 15 is recovered based on the TAG). Therefore, a part of the interface device 15 for transmitting the AIS cell is transmitted. Even if a failure occurs, the failure can be surely recognized and appropriate measures can be taken.

Further, as described above, when an AIS cell is transmitted from each interface device 15 other than the fault interface device 15, each interface device (including the fault interface device) 15 has a fault in the fault interface device 15. Restored and AIS cell control unit 15-4
The cell counter 15-6 for the corresponding connection (VPI / VCI) is stopped counting until the transmission of the AIS cell from the cell is stopped. Therefore, in this case as well, unnecessary charging at the time of failure can be surely prevented. , You can always do accurate billing.

Now, as described above, when a failure occurs in the interface device 15, the failed interface device 15 cannot send an AIS cell. In this case, for example, the concentrator 16 is used instead. AI
S cells can also be sent. Below, such AT
A method of coping with a failure in the M cell switch 11 will be described.

First, when a failure occurs in a certain interface device 15 among the interface devices 15, in the line concentrator 16 that collects the input / output information of the interface device 15, that fact is notified to the interface device failure detection unit 16. -1 is detected. Then, in the concentrator 16, the microprocessor 16-3 as the connection information extraction unit causes the connection data storage unit 1 to operate.
The connection data (see FIG. 14) stored in 6-2 is searched, and the data (VPI / VCI) for all the connections (VPC / VCC) connected to the fault interface device 15 is extracted. A
The IS cell image creation unit 16-4 is notified.

Then, the AIS cell image creating section 16-
4, V notified from the microprocessor 16-3
Based on the PI / VCI, a predetermined bit image is written in the payload type identifiers and payload portions of all the cells to be input, and this is input to the VCC table 16-5, so that it is extracted by the microprocessor 16-3. For all connections (VPC / VCC)
The AIS cell is sent to the ATM switch 12 side.

At this time, the fault interface device 1
5, in this case also, the cell counter control unit 15-7 stops the counting of the cell counter 15-6. Then, when the fault in the fault interface device 15 is recovered, the main control unit 13 notifies the interface device 15 other than the fault interface device to that effect, and in the concentrator 16 which has received this notice, the microprocessor 15
The transmission of the AIS cell from the AIS cell control unit 15-4 is stopped by -8, and in the interface device 15 where the failure is recovered, the cell counter control unit 15-7 restarts the counting of the cell counter 15-6. .

As described above, according to the ATM switch 11 (concentrator 16) of this embodiment, when the concentrator 16 detects that the interface device 15 has failed, the failed interface device 15 is restored. , From the concentrator 16 to all connections (VPC /
Since the AIS cell is sent to the (VCC), even if a failure occurs in the interface device 15 for sending the AIS cell, the concentrator 16 sends the AIS cell to notify the failure occurrence to all connections. Can be notified by
For a failure in this interface device 15,
You will be able to take appropriate measures.

Further, in the fault interface device 15,
The count of the cell counter 15-6 is stopped until the failure is recovered and the transmission of the AIS cell from the concentrator 16 is stopped. In this case as well, unnecessary charging is surely prevented, and accurate counting is always performed. Can be charged. (A4) When a failure occurs in the ATM switch 12 Next, a method of dealing with a failure in the ATM switch 11 when a failure occurs in the ATM switch 12 will be described below.

First, for example, in the ATM switch 12 shown in FIG. 12, if a failure occurs in the switching element 12B-2 constituting the second switch stage 12B,
The tag information about the switching element 12B-2 of the failed intermediate switch stage 12B is notified to all the interface devices 15 housed in the main control unit 13.

In each interface device 15 that has received the notification of the tag information, as described above with reference to FIG. 15 (as in the case where a failure occurs in the interface device 15),
The microprocessor 15-8 searches the connection data storage unit 15-5 to extract the VPI / VCI of the path that matches the notified tag information, and the AIS control unit 1
A to A for the path having this VPI / VCI by 5-4
The IS cell is transmitted and the cell counter control unit 15
By -7, the count of each cell counter 15-6 of the connection (VPC / VCC) having the above VPI / VCI is stopped.

Then, when the failure of the intermediate switch stage 12B (switching element 12B-2) in the ATM switch 12 is recovered, a notice to that effect is sent to all the interface devices 15 accommodated in the main control unit 13 as tag information. In response to this notification, the interface device 15 receives the VPI / VCI of the path matching the notified tag information by the microprocessor 15-8 in the connection data storage unit 15-, as in the process described above with reference to FIG. 8 is detected and detected from the AIS cell controller 8 and is notified to the AIS cell controller 15-4 and the cell counter controller 15-7.

Then, the AIS cell control unit 15-4 stops the transmission of the AIS cell to the notified VPI / VCI path, and the cell counter control unit 15-7 causes the VPI / VCI / VPI / VCI path.
The cell counter 15-6 of the connection (VPC / VCC) having VCI is restarted. in this way,
According to the ATM switch 11 in this embodiment, the ATM switch 12 having the three switch stages 12A to 12C is provided.
In the above, when a failure occurs in the second (intermediate) switch stage 12B (switching element 12B-2), the failure switch stage 12B (switching element) for all interface devices 12 accommodated in the main control unit 13 12
B-2) is notified of the tag information, and the interface device 15 that has received the notification sends an AIS cell to the path that matches the notified tag information.
Even if a failure occurs in the TM switch 12, the fact that a failure has occurred in the ATM switch 12 can be reliably recognized by sending an AIS cell from each interface device 15, and appropriate measures can always be taken.

Also in this case, in each interface device 15, the cell counter 15-6 is sent until the faulty switch stage 12B is restored together with the transmission of the AIS cell.
Since the counting is stopped, unnecessary charging can be surely prevented, and accurate charging can always be performed. In addition,
The interface device 15 shown in FIG. 13 includes only the line layer failure monitor 15-1, the cell counter 15-6 and the cell counter controller 15-7, or the AIS cell monitor 15-3, the cell counter 15-6 and the cell. Only the counter control unit 15-7 may be provided to stop the counting of the cell counter 15-6 when a failure occurs in the line layer or when an AIS cell is received. Unit 15-4, connection data storage unit 15-5, cell counter 15-6, cell counter control unit 15-7, microprocessor 15-8
Therefore, the AIS cell may be sent to the line side and the count of the cell counter 15-6 may be stopped when a failure occurs in the other interface device 15.

(B) Description of Second Embodiment FIG. 17 is a block diagram showing the structure of an ATM exchange as a second embodiment of the present invention. In FIG. 17, FIG.
13 are the same as those described above with reference to FIG. 13, but in the present embodiment, the interface device 1 is different from that shown in FIG.
5 is different from the AIS cell monitoring unit 15-3 in that it includes an RDI cell monitoring unit 15-3 '.

Here, the RDI cell monitoring unit (far end reception failure cell detection unit) 15-3 'is an AIS when a failure occurs in the ATM layer that handles cell multiplexing and switching (when an AIS cell is transmitted). The RDI cell issued from the terminating device 17 as a cell response is detected. In addition, the cell counter control unit 15-7 in the present embodiment uses the RD
Even when the R cell is detected by the I cell detection unit 34,
Based on the VPI / VCI in the RDI cell, the count of the cell counter 15-6 for the corresponding connection (VPC / VCC) is stopped, while the RDI cell monitoring unit 15-3 'detects the stop of the transmission of the RDI cell. When done,
Cell counter 15-6 for the corresponding connection
It is designed to restart counting.

With such a configuration, in the above-mentioned ATM switch 11, in addition to the processing described in the first embodiment,
RD issued from the terminating device 17 when the ATM layer fails
I-cell is received by the interface device 15 and this RD
Even when the I cell is detected by the RDI cell monitoring unit 15-3 ', the cell for the corresponding connection (VPC / VCC) is determined by the cell counter control unit 15-7 based on the VPI / VCI in the RDI cell. The counting of the counter 15-6 is stopped.

Then, the ATM layer failure is restored and A
The transmission of the IS cell is stopped, and the RDI cell monitoring unit 15-
When the transmission stop of the RDI cell is detected at 3 ', the interface device 15 of the cell counter controller 15-7
Causes the cell counter 15-6 to restart counting for the corresponding connection (VPC / VCC). As described above, according to the ATM switch 11 (interface device 15) in the present embodiment, even when the interface device 15 receives the RDI cell output from the terminating device 17 when the ATM layer fails, the interface device 15 can: Termination device 1 after the ATM layer failure is recovered
Until the transmission of the RDI cell from 7 is stopped, the cell counter 15-6 for the corresponding connection is stopped, and in this case as well, unnecessary charging at the time of failure is surely prevented, and accurate counting is always performed. Can be charged.

The interface device 1 shown in FIG.
5, like the first embodiment, the RDI cell monitoring unit 15-
3 ', the cell counter control unit 15-7 and the cell counter only may be provided, and the count of the cell counter 15-6 may be stopped when the RDI cell is detected. (C) Description of Third Embodiment FIG. 18 is a block diagram showing a configuration of an ATM exchange according to a third embodiment of the present invention.
Those denoted by the same reference numerals as those shown in FIG.
In the present embodiment, the interface device 15 includes a regular cell sending unit 15-10 and a regular cell extracting unit 15-11 in addition to the components described above with reference to FIG. Concentrator 16
However, the dedicated flag check unit 16-6 and the cell buffer 16
-7 and all tag generation units 16-8.

Here, first, in the interface device 15, a fixed cell transmission unit (activation cell transmission unit) 15-10.
Is a PVC (P
A cell (activation cell) indicating that it is operating normally at a predetermined cycle (for example, every second) is periodically transmitted to another interface device 15 via the ermanent Virtual Channel). The regular cell extraction unit (activated cell monitoring unit) 15-11 monitors activated cells from the interface devices 15 other than itself.

In the present embodiment, in addition to the processes described above with reference to FIG. 13, the AIS cell control unit (alarm cell transmission unit) 15-4 uses the regular cell extraction unit 15-11 to activate cells. Is detected at a predetermined interval, the AIS cell is transmitted to all the connected paths, and the cell counter control unit (billing counter control unit) 15-7 Similarly, when the regular cell extracting unit 15-11 detects that the activated cells do not arrive at a predetermined interval, the cell counter 15-6 stops counting.

The AIS controller 15-4 described above is
After sending out the IS cell, the regular cell extracting unit 15-11
When it is detected that the activated cells have arrived again at a predetermined interval, the transmission of the AIS cell is stopped, and the cell counter control unit 15-7 makes the AIS cell as described above.
When the transmission of the AIS cell by the control unit 15-4 is stopped,
The counting of the cell counter 15-6 is restarted.

On the other hand, in the line concentrator 16, the dedicated flag check unit (dedicated cell capturing unit) 16-6 checks the dedicated flag of the cell transmitted from the interface device 15 on which the line is concentrating, and the OEid ( This is to capture the own-station dedicated cell having the identification information unique to each interface device 15 or the tag information (routing information).

[0115] In the interface cell 15 of the own-cell dedicated cell, a storage area dedicated to the station is added to the cell header, and a dedicated cell flag (for example, dedicated cell: "1", normal cell: "0") is added to the area. , And its format is, for example, as shown in FIG. 19, a dedicated cell flag, cell header (setting data: VPI, VCI, etc.), OEid (device type: x
x, device number: yy).

Further, the cell buffer 16-7 takes in the dedicated cell captured by the dedicated flag check unit 16-6 and temporarily holds it, and stores the dedicated cell in a plurality of portions to send it to all the interface devices 15. The all-tag generation unit 16-8 generates tag information for all the interface devices 15, for example, by the algorithm shown in FIG.
It is given to each dedicated cell from -7 and sent to the ATM switch 12 side.

That is, in the present embodiment, the cell buffer 16-7 and the all-tag generating section 16-8 are used to add all the tag information to the dedicated cells and copy a plurality of dedicated cells having the same contents. A conversion copying unit is realized. With such a configuration, the above-described ATM exchange 11 can perform the following processing in addition to the processing in the ATM exchange 11 described above with reference to FIG.

That is, first, in the concentrator 16,
The own-cell dedicated cell in which the dedicated cell flag from the interface device 15 is set is the dedicated flag check unit 16-6.
Then, the cell buffer unit 16-7 and the all-tag generation unit 16-8 add all the tag information to the own-station dedicated cell, and copy a plurality of own-station dedicated cells having the same contents. It is sent to the ATM switch 12 side.

Then, the interface device 15 which has received the own-station dedicated cell automatically identifies and specifies the interface device 15 which has transmitted the own-station dedicated cell, and based on this, each interface can be very easily Device 1
Between 5 and 5, the PVC for exclusive use in the own station is connected (set). After that, in this ATM exchange 11, for example, in the image as shown in FIG. 21, from the fixed cell sending unit 15-10 of each interface device 15, each activated cell has a predetermined cycle and another activated device via the PVC. In addition to being sent to 15, the regular cell extraction unit 15-11
The activated cells from the interface devices 15 other than itself are monitored.

Then, the interface device 15 which has received the fixed cell from the other interface device 15 sequentially stores the arrival of the activated cell in a storage table such as a memory, and stores the storage table after a certain period of time. If there is an interface device 15 for which an activated cell has not arrived, it is determined that some failure has occurred in the interface device 15, and the microprocessor 15-8 causes the failed interface device 15 to fail.
The connection (VPC / VCC) that passes through
This is notified to the AIS cell control unit 15-4 and the cell counter control unit 15-7.

Upon receiving this notification, the AIS cell control unit 15-
4. The cell counter control unit 15-7 sends the AIS cell to the path that matches the notified VPC / VCC, and stops the cell counter 15-6. That is, in the ATM switch 11 according to the present embodiment, the P between the interface devices 15 is set.
Through the VC, each interface device 15 notifies the other interface device 15 of the activated cell at a predetermined cycle, and each interface device 15 monitors the activated cells from the other interface devices 15 than itself. If the activated cells do not arrive at a predetermined interval, the AIS cells are sent to all the connected paths.

Then, when it is detected that the activated cells have arrived again at a predetermined interval after the alarm cell is transmitted as described above, the interface device 15 outputs a message from the fixed cell transmitter 15-10. The transmission of the AIS cell is stopped, and the cell counter control unit 15-7 restarts the counting of the cell counter 15-6. Thus, according to the ATM switch 11 (interface device 15) of this embodiment, each interface device 15
Notifies other interface devices 15 of the activated cells in a predetermined cycle, monitors activated cells from the interface devices 15 other than itself, and when the activated cells do not arrive at a predetermined interval, Since the AIS cells are sent to all the connected paths until the activated cell arrives again at a predetermined interval, the interface device 15 in which a failure has occurred can be identified very easily, and the failure can be quickly detected. You will be able to respond.

Also in this case, the interface device 1
In 5, when the AIS cell is transmitted as described above, the cell counter 15-6 stops counting until the activated cell arrives again at a predetermined interval and stops transmitting the AIS cell. With certainty, it is possible to always perform accurate billing. Note that the interface device 15 shown in FIG. 18 also uses the AIS as in the first embodiment.
Only the cell control unit 15-4, the cell counter 15-6, the cell counter control unit 15-7, the fixed cell transmission unit 15-10, and the fixed cell extraction unit 15-11 are provided, and the activated cell arrives at a predetermined cycle. If not, the AIS cell may be sent to the line side and the counting of the cell counter 15-6 may be stopped.

(D) Description of Fourth Embodiment FIG. 22 is a block diagram showing the structure of an ATM exchange as a fourth embodiment of the present invention.
Those denoted by the same reference numerals as those shown in FIG.
Although the same as the above-mentioned one, the ATM switch 11 in this embodiment has the interface device 15
However, in addition to the configuration shown in FIG. 13, an AIS tagged cell extraction unit 15-12 and an AIS generation unit 15-13 are provided, while the concentrator 16 is replaced with the AIS cell image creation unit 16-4 shown in FIG. AIS tag setting unit 16-
It is configured with 4 '.

First, in the line concentrator 16, A
The IS tag setting unit (alarm cell information transmitting unit) 16-4 'is
When the interface device failure monitoring unit 16-1 detects a failure of the interface device 15, a bit (information) indicating that the cell is an AIS cell is added to the tag area of the input cell, and the cell is sent to the ATM switch 12. Is.

On the other hand, in the interface device 15,
Cell extractor with AIS tag (alarm cell information receiver) 15
-12 receives a cell to which a bit indicating that it is an AIS cell is received, and the AIS cell creation unit (pseudo alarm cell creation unit) 15-13 is used by the AIS tagged cell extraction unit 15- When a cell having a bit indicating that it is an AIS cell is received at 12, a pseudo AIS cell (pseudo alarm cell) is created and sent to the line side.

The cell counter control unit 15-7 in the present embodiment has a function in addition to the operation described above with reference to FIG.
Even when the AIS-tagged cell extraction unit 15-13 receives a cell to which a bit indicating that it is an AIS cell is received,
The counting of the cell counter 15-6 is stopped. With such a configuration, in the above-mentioned ATM switch 11, in addition to the processes described above with reference to FIG.
In the concentrator 16, the fact that a failure has occurred in the interface device 15 causes the interface device failure detection unit 16-
When it is detected at 1, the AIS tag setting unit 16-4 'adds a bit indicating that it is an AIS cell in the tag area of the input cell, and this is added via the VCC table 16-5 to the ATM. It is sent to the switch 12 side.

Then, the cell to which the bit indicating that it is this AIS cell is added is the AI of another interface device 15.
When received / extracted by the S-tagged cell extracting unit 15-12, the interface device 15 creates a pseudo AIS cell by the AIS cell creating unit 15-13, sends the pseudo AIS cell to the line side, and controls the cell counter. Part 15
The count of the cell counter 15-6 is stopped by -7.

As described above, according to the ATM switch 11 of this embodiment, when the concentrator 16 detects that a failure has occurred in the interface device 15, the concentrator 16 gives a bit indicating that it is an AIS cell. The interface device 15 which has transmitted the generated cell to the ATM switch 12 and which has received this cell creates a pseudo AIS cell and transmits it to the line side.
6. While minimizing the scale and load of the interface device 15, the fact that a failure has occurred in the interface device 15 can be notified to the line side, and the fact that the above failure has occurred is recognized and appropriate measures are taken. You can

Also in this case, in the interface device 15 which has received the cell to which the bit indicating the above-mentioned AIS cell is added, the cell counter 15-6 stops counting, so that unnecessary charging is surely prevented. Therefore, accurate billing can always be performed.

[0131]

As described above in detail, according to the method of coping with a failure in the fixed length cell switch and the interface device attached to the fixed length cell switch according to the present invention, the cell multiplexing
When the interface unit receives an alarm cell issued at the time of a failure of the switching layer, the interface unit stops the counting of the charging counter for the corresponding connection until the failure is recovered and the sending of the alarm cell is stopped. Therefore, it is possible to reliably prevent unnecessary billing at the time of a failure and always perform accurate billing (claims 1 to 4).

Further, according to the method of coping with the occurrence of a failure in the fixed-length cell switch and the interface device attached to the fixed-length cell switch of the present invention, when the failure of the cell-multiplexing / switching layer occurs, the terminating device (subscription of the cell-multiplexing / switching layer) is added. When the interface unit receives a far-end reception faulty cell sent from a user terminal), the interface unit waits until the above-mentioned fault is recovered and the transmission of the far-end reception faulty cell is stopped.
Since the counting of the billing counter for the corresponding connection is stopped, unnecessary billing at the time of failure can be surely prevented, and accurate billing can always be performed (claims 5 to 8).

Further, according to the method for coping with the occurrence of a failure in the fixed-length cell switch of the present invention and the interface device attached to the fixed-length cell switch, when a failure occurs in a certain interface section among a plurality of interface sections, the failure occurs. Based on the unique identification information or routing information about the interface section, an alarm cell is sent from the interface section other than the failed interface section to the path connected to the failed interface section until the failure is recovered. Even if a failure occurs in one interface section for sending cells, the failure can be surely recognized and appropriate measures can be taken (claims 9, 10, 1).
3, 15, 16, 19, 20).

Further, as described above, even when the interface section sends out the alarm cell, the count of the charging counter is counted until the failure in the faulty interface section is recovered and the output of the alarm cell is stopped in the interface section. Since the charging is stopped, unnecessary charging at the time of failure can be surely prevented, and accurate charging can be always performed (claims 11 to 14, 17 to 20).

Furthermore, according to the method of coping with the occurrence of a failure in the fixed length cell switch and the concentrator of the fixed length cell switch of the present invention, when the concentrator detects a failure in the interface section, the failure occurs. Until the interface unit is restored, the concentrator sends alarm cells to all connections, so even if a failure occurs in the interface unit for sending alarm cells, the alarm cells are sent from the concentrator, The fact that a failure has occurred can be notified to all connections, and appropriate measures can be taken against failures in this interface section at all times (claims 21, 22, 25, 26).

As described above, when the alarm cell is sent from the concentrator, the failure interface unit waits until the failure is recovered and the alarm cell is stopped from being sent from the concentrator.
Since the counting of the billing counter is stopped, unnecessary billing can be surely prevented also in this case, and accurate billing can always be performed (claims 23 and 24). Further, according to the coping method when a failure occurs in the fixed-length cell switch and the interface device attached to the fixed-length cell switch of the present invention, each interface unit notifies the other interface unit of the activated cell at a predetermined cycle. , Activated cells from interface units other than itself are monitored, and if the activated cells do not arrive at the specified interval, all the connected paths are re-established until the activated cells arrive again at the specified interval. Since the alarm cell is sent to the device, it is possible to very easily identify the faulty interface section and quickly deal with the fault (claim 27,
28, 31).

Also in this case, when the alarm cell is sent out as described above, the interface counter keeps counting the charging counter until the activated cell arrives again at a predetermined interval and stops sending out the alarm cell. Since it is stopped, unnecessary charging can be surely prevented, and accurate charging can be always performed (claims 29 to 32). Further, according to the concentrator of the fixed-length cell switch of the present invention, the own-station dedicated cell having the identification information unique to the interface unit or the routing information from the interface unit is captured, and all the routing information is stored in the own-station dedicated cell. Is added and a plurality of own-station-dedicated cells having similar contents are copied and transmitted, the interface unit that has received this own-station-dedicated cell identifies the interface unit of the transmission source of the own-station-dedicated cell. It becomes possible to easily perform a required process such as specifying and establishing a dedicated permanent connection with the interface section (claim 33).

Further, according to the method for coping with the occurrence of a failure in the fixed-length cell switch of the present invention, when a failure occurs in the intermediate switch stage in the exchange switch section having three or more switch stages, the fixed-length cell switch is provided. (Main control unit) notifies all interface units accommodated of the routing information about the faulty switch stage, and the interface unit receives this notification and responds to the path that matches the notified routing information. Therefore, even if a failure occurs in the exchange switch section, the alarm cell can be sent out from the interface section and the fact can be surely recognized, so that appropriate measures can be taken at all times (claims). 34, 35).

In this case as well, in the interface unit, the alarm cell is sent and the count of the charging counter is stopped until the faulty intermediate switch stage is restored, so that unnecessary charging is surely prevented. , Accurate billing can always be performed (claims 36 and 37). Furthermore, according to the method for coping with a failure in the fixed-length cell switch of the present invention and the fixed-length cell switch, when the concentrator detects a failure in the interface, the concentrator indicates that the cell is an alarm cell. The cell to which the information is added is sent to the exchange switch section, and the other interface section that receives this cell creates a pseudo alarm cell and sends it to the line side. It is possible to reliably notify the line side of the occurrence of the above-mentioned failure and take appropriate measures while minimizing the load and load (claims 38 and 40).

In this case as well, in the interface section that has received the cell to which the information indicating that the alarm cell is added, the counting of the billing counter is stopped, so that unnecessary billing is reliably prevented and , Accurate billing can be performed (claims 39 and 41). Further, according to the coping method when a failure occurs in the fixed-length cell switch of the present invention and the interface device attached to the fixed-length cell switch, when the interface unit detects a failure of the line layer, the interface unit detects the failure of the line layer. Until it is restored
Since the counting of the billing counters for all the connections is stopped, unnecessary billing at the time of failure can be surely prevented and accurate billing can always be performed (claims 42 to 45).

[Brief description of the drawings]

FIG. 1 is a principle block diagram of the present invention.

FIG. 2 is a principle block diagram of the present invention.

FIG. 3 is a principle block diagram of the present invention.

FIG. 4 is a principle block diagram of the present invention.

FIG. 5 is a principle block diagram of the present invention.

FIG. 6 is a principle block diagram of the present invention.

FIG. 7 is a principle block diagram of the present invention.

FIG. 8 is a principle block diagram of the present invention.

FIG. 9 is a principle block diagram of the present invention.

FIG. 10 is a principle block diagram of the present invention.

FIG. 11 is a block diagram showing a configuration of an ATM exchange according to the first embodiment of the present invention.

FIG. 12 is an ATM in an ATM exchange according to the first embodiment.
It is a block diagram which shows the structure of a switch.

FIG. 13 is a block diagram showing configurations of an interface device and a line concentrator in the ATM exchange according to the first embodiment.

FIG. 14 is a diagram showing an example of a format of connection data used in the ATM switch of the first embodiment.

FIG. 15 is a flowchart for explaining a coping method when a failure occurs in the ATM exchange according to the first embodiment.

FIG. 16 is a flowchart for explaining a coping method when a failure occurs in the ATM exchange according to the first embodiment.

FIG. 17 is a block diagram showing a configuration of an ATM exchange as a second embodiment of the present invention.

FIG. 18 is a block diagram showing a configuration of an ATM exchange as a third embodiment of the present invention.

FIG. 19 is a diagram showing an example of a format of a dedicated cell used in the ATM switch of the third embodiment.

FIG. 20 is a diagram showing an example of an algorithm for generating all tags in the ATM switch of the third embodiment.

FIG. 21 is a diagram for explaining the operation of the ATM exchange of the third embodiment.

FIG. 22 is a block diagram showing a configuration of an ATM exchange as a fourth embodiment of the present invention.

FIG. 23 is a block diagram showing a schematic configuration of a general ATM switching network.

[Explanation of symbols]

1 Fixed Length Cell Switch 2 Exchange Switch Section 3,15 Interface Section (Interface Device) 4,13 Main Control Section 5,16 Concentrator Section (Concentrator) 11 ATM Switch (Fixed Length Cell Switch) 12 ATM Switch 12A-12C Switch Stage 12A-1 to 12A-N, 12B-1 to 12B-N, 1
2C-1 to 12C-N switching element 14 Main storage unit 15-1 Line layer fault monitoring unit (line layer fault detection unit) 15-2 ATM layer fault monitoring unit 15-2 ATM layer fault monitoring / AIS cell generation unit 15- 3 AIS cell monitoring unit (alarm cell detection unit) 15-3 'RDI cell monitoring unit (far end reception failure cell detection unit) 15-4 AIS cell control unit (alarm cell transmission unit) 15-5 Connection data storage unit (identification) Information storage unit, routing information storage unit) 15-6 Cell counter (billing counter) 15-7 Cell counter control unit (billing counter control unit) 15-8 Microprocessor (μP: identification information receiving unit, routing information receiving unit, path Detection unit) 15-9 Buffer 15-10 Periodic cell transmission unit (activation cell transmission unit) 15-11 Periodic cell extraction unit (activation cell) View part) 15-12 Cell extraction part with AIS tag (alarm cell information reception part) 15-13 AIS cell creation part (pseudo alarm cell creation part) 16-1 Interface device failure monitoring part (fault detection part) 16-2 Connection Data storage unit (connection information storage unit) 16-3 Microprocessor (μP: connection information extraction unit) 16-4 AIS cell image creation unit (alarm cell transmission unit) 16-4 'AIS tag setting unit (alarm cell information transmission unit) ) 16-5 Virtual Channel Connection (VCC)
Table 16-6 Dedicated flag check unit (dedicated cell capturing unit) 16-7 Cell buffer 16-8 All tag generation unit 17 Termination device 21-1 to 21-N switch stage 31 Charging counter 32, 39, 44, 48, 54 Alarm cell detection unit 33, 35, 40, 45, 49, 62 Charging counter control unit 34 Far end reception failure cell detection unit 36 Identification information storage unit 37 Identification information reception unit 38, 43 Path detection unit 41 Routing information storage unit 42 Routing Information receiving unit 46 Activated cell sending unit 47 Activated cell monitoring unit 51 Failure detection unit 52 Connection information storage unit 53 Connection information extraction unit 55 Special cell supplement unit 56 Cell conversion copying unit 57 Interface unit failure detection unit 58 Alarm cell information transmission Part 58 59 Alarm cell information receiver 60 Pseudo alarm cell generator 61 Line layer failure Harm detector

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Sumie Morita, 1015 Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa, within Fujitsu Limited

Claims (45)

[Claims] 1. A fixed-length cell switch that handles fixed-length cells by providing a switching switch unit and an interface unit attached to the input / output unit of the switching switch unit, and cell multiplexing that handles multiplexing and switching of cells. When the interface unit receives an alarm cell issued at the time of a failure of the switching layer, the interface unit stops counting of the billing counter for the corresponding connection. Workaround. 2. The fixed length according to claim 1, wherein when the interface unit detects the stop of the transmission of the alarm cell, the interface unit restarts counting of the billing counter for the corresponding connection. What to do when a failure occurs in a cell switch. 3. An interface device attached to an input / output unit of a switching switch unit of a fixed-length cell switch that handles fixed-length cells, and is issued when a failure occurs in a charging counter and a cell multiplexing / switching layer that handles multiplexing and switching of cells. An alarm cell detection unit for detecting an alarm cell and a charging counter control unit for stopping the counting of the charging counter for the corresponding connection when the alarm cell is detected by the alarm cell detection unit. An interface device equipped with a fixed-length cell switch, characterized in that 4. The charging counter control unit is configured to restart the counting of the charging counter for the corresponding connection when the alarm cell detection unit detects that the alarm cell has stopped being sent. An interface device provided with a fixed-length cell switch according to claim 3, characterized in that: 5. A fixed-length cell switch that handles fixed-length cells by providing a switching switch unit and an interface unit attached to the input / output unit of the switching switch unit, and cell multiplexing that handles multiplexing and switching of cells. When the interface unit receives a far-end reception failure cell that is output from the terminating device of the cell multiplexing / switching layer at the time of failure of the switching layer, the interface unit may stop counting of the charging counter for the corresponding connection. A characteristic method for coping with a failure in a fixed-length cell switch. 6. When the interface unit detects the stop of transmission of the far-end reception failure cell, the interface unit:
6. The method for coping with a failure in a fixed-length cell switch according to claim 5, wherein counting of the billing counter for the corresponding connection is restarted. 7. An interface device attached to an input / output unit of a switching switch unit of a fixed-length cell switch that handles fixed-length cells, wherein a charging counter and a cell multiplexing / switching layer for handling cell multiplexing / switching fail when the cell fails. If the far-end reception faulty cell detection unit detects a far-end reception faulty cell emitted from the terminating device of the multiplexing / switching layer, and the far-end reception faulty cell detection unit detects the far-end reception faulty cell, it is applicable. An interface device equipped with a fixed-length cell switch, comprising an accounting counter control unit for stopping counting of the accounting counter for a connection. 8. The charging counter control unit restarts the counting of the charging counter for the corresponding connection when the far-end reception failure cell detection unit detects that the far-end reception failure cell has stopped being transmitted. The interface device provided with a fixed-length cell switch according to claim 7, wherein the interface device is attached to the fixed-length cell switch. 9. A fixed-length cell for handling a fixed-length cell by including an exchange switch unit, a main control unit for the exchange switch unit, and a plurality of interface units attached to input / output units of the exchange switch unit. In a long cell switch, when connecting a path for each interface unit, add unique identification information about the opposite device to the path information,
When a path is set and a failure occurs in a certain interface section of the plurality of interface sections, the main control section identifies the interface section other than the failed interface section with a unique identification of the failed interface section. The interface section that has notified the information and has received the notification of the unique identification information about the faulty interface section sends an alarm cell to a path that matches the notified unique identification information. What to do when a failure occurs in a fixed-length cell switch. 10. When the fault in the fault interface unit is recovered, the main control unit notifies the interface units other than the fault interface unit to that effect, and the interface unit that receives the notification issues the alarm. 10. The method for coping with a failure in the fixed length cell switch according to claim 9, characterized in that transmission of cells is stopped. 11. The interface unit, which has been notified of the unique identification information of the failed interface unit, sends out the alarm cell to a path that matches the notified unique identification information, and charges. 11. The method for coping with a failure in a fixed length cell switch according to claim 10, wherein the counting of the counter is stopped. 12. When the fault in the fault interface unit is recovered, the main control unit notifies the interface units other than the fault interface unit to that effect, and the interface unit receiving the notification issues the alarm. The method for coping with a failure in a fixed-length cell switching system according to claim 11, wherein the transmission of cells is stopped and the counting of the charging counter is restarted. 13. An interface device attached to an input / output unit of an exchange switch unit of a fixed-length cell switch that handles fixed-length cells, a charging counter, and an identification information storage unit that stores unique identification information about an opposite device. An identification information receiving unit that receives unique identification information about the fault interface unit from the main control unit for the exchange switch unit, and a notification of the unique identification information about the fault interface unit at the identification information receiving unit. When receiving, a path detection unit that searches the identification information storage unit and detects a path that matches the notified unique identification information, and sends an alarm cell to the path detected by the path detection unit And an accounting cell control section for stopping the counting of the accounting counter for the path detected by the path detecting section. An interface device equipped with a fixed-length cell switch characterized by being configured. 14. The alarm cell sending unit is configured to stop sending of the alarm cell when receiving a notification from the main control unit that a failure in the failure interface unit has been recovered, The billing counter control unit is configured to restart counting of the billing counter when transmission of the alarm cell by the alarm cell transmission unit is stopped.
An interface device provided with a fixed length cell switch according to claim 13. 15. A fixed switch for handling a fixed-length cell by comprising an exchange switch unit, a main control unit for the exchange switch unit, and a plurality of interface units attached to input / output units of the exchange switch unit. In a long cell switch, when a failure occurs in a certain interface section of the plurality of interface sections, the main control section notifies the interface sections other than this failure interface section with routing information about the failed interface section. In the fixed length cell switching system, the interface unit that has received the notification of the routing information about the failed interface unit sends an alarm cell to the path that matches the notified routing information. What to do when it occurs. 16. When the fault in the fault interface unit is recovered, the main control unit notifies the interface units other than the fault interface unit to that effect, and the interface unit that receives the notification sends the alarm cell. 16. The method for coping with the occurrence of a failure in the fixed-length cell switch according to claim 15, wherein the sending of the message is stopped. 17. The interface unit, which has received the notification of the routing information about the fault interface unit, sends the alarm cell to the path that matches the notified routing information and counts the charging counter. The method for coping with a failure in the fixed-length cell switch according to claim 16, characterized by stopping. 18. When the fault in the fault interface unit is recovered, the main control unit notifies the interface units other than the fault interface unit to that effect, and the interface unit that receives the notification issues the alarm. 18. The method for coping with a failure in a fixed length cell exchange according to claim 17, wherein the transmission of cells is stopped and the counting of the billing counter is restarted. 19. An interface device attached to an input / output unit of an exchange switch unit of a fixed length cell switch for handling fixed length cells, comprising: a billing counter, a routing information storage unit for storing routing information, and the exchange switch unit. Routing information receiving section for receiving the routing information about the fault interface section from the main control section of the above, and when the routing information receiving section receives the notification of the routing information about the fault interface section, the routing information storage section is searched. Then, a path detection unit that detects a path that matches the notified routing information, an alarm cell transmission unit that transmits an alarm cell to the path detected by the path detection unit, and the path detection unit A billing counter control unit for stopping the counting of the billing counter for the detected path is provided. An interface device equipped with a fixed-length cell switch, which is characterized by being configured. 20. The alarm cell transmission unit is configured to stop the transmission of the alarm cell when receiving a notification from the main control unit that the failure in the failure interface unit has been recovered, The billing counter control unit is configured to restart counting of the billing counter when transmission of the alarm cell by the alarm cell transmission unit is stopped.
An interface device provided with a fixed-length cell switch according to claim 19. 21. An exchange switch unit, a main control unit for the exchange switch unit, a plurality of interface units attached to the input / output units of the exchange switch unit, and input / output information of the plurality of interface units. By providing a concentrator for concentrating lines, in a fixed-length cell switch that handles fixed-length cells, when the concentrator detects a failure in the interface unit, the concentrator alerts all connections. A method of coping with a failure in a fixed-length cell switch, which is characterized by transmitting cells. 22. When the fault in the fault interface unit is recovered, the main control unit notifies the interface units other than the fault interface unit to that effect, and the concentrator that has received the notification issues the alarm. 13. The method for coping with a failure in a fixed length cell switch according to claim 12, characterized in that transmission of cells is stopped. 23. In the concentrator, when it is detected that a failure has occurred in the interface,
22. The method for coping with a failure in a fixed-length cell switch according to claim 21, wherein the alarm cell is sent to all the connections and the failure interface section stops counting the charging counter. 24. When the fault in the fault interface unit is restored, the main control unit notifies the interface units other than the fault interface unit to that effect, and the line concentrating unit that has received the notification issues the alarm. 22. The method for coping with a failure in a fixed-length cell switch according to claim 21, wherein the transmission of cells is stopped and the interface section which has recovered from the failure restarts the counting of the charging counter. 25. In a concentrator for concentrating input / output information of a plurality of interface units attached to an input / output unit of an exchange switch unit of a fixed length cell switch that handles fixed length cells, a failure has occurred in the interface unit. A failure detection unit that detects a failure, a connection information storage unit that stores connection information connected to the interface unit, and the failure detection unit that detects a failure in the interface unit For the connection information extraction unit that retrieves the connection information stored in the information storage unit and extracts all the connection information connected to the failure interface unit, and for all the connections extracted by the connection information extraction unit, And an alarm cell sending unit for sending an alarm cell. Length cell switch attached concentrator. 26. The alarm cell transmission unit is configured to stop the transmission of the alarm cell when the notification that the failure of the interface unit has been recovered is received. A line concentrator equipped with the fixed length cell switch described above. 27. A fixed-length cell for handling a fixed-length cell by including an exchange switch unit, a main control unit for the exchange switch unit, and a plurality of interface units attached to an input / output unit of the exchange switch unit. In the long cell switch, each interface unit has a predetermined cycle through a dedicated permanent connection unit provided between the interface units.
In addition to notifying the activated cells to other interface units, each interface unit monitors the activated cells from other interface units, and if the activated cells do not arrive at a predetermined interval, the connection is made. A method for coping with a failure in a fixed-length cell switch, which is characterized in that an alarm cell is transmitted to all the established paths. 28. The transmission of the alarm cell is stopped when the activation cell is detected to arrive at a predetermined interval after the transmission of the alarm cell.
What to do when a failure occurs in the fixed-length cell switch described above. 29. When the activated cell from an interface unit other than itself does not arrive at a predetermined interval, the alarm cell is sent to all connected paths and the counting of the charging counter is stopped. 28. A method for coping with a failure in a fixed length cell switch according to claim 27. 30. After the alarm cell is transmitted, when it is detected that the activated cell has arrived at a predetermined interval, the alarm cell transmission is stopped and the accounting counter is restarted. 28. A method of coping with a failure in a fixed-length cell switch according to claim 27. 31. An interface device attached to an input / output unit of an exchange switch unit of a fixed-length cell switch for handling fixed-length cells, wherein a charging counter and a dedicated permanent connection unit provided between other interface units are used. Then, in a predetermined cycle, an activated cell transmission unit that transmits an activated cell to another interface unit, an activated cell monitoring unit that monitors the activated cell from an interface unit other than itself, and an activated cell monitoring unit. When the cell monitoring unit detects that the activated cell does not arrive at a predetermined interval, it outputs an alarm cell to all connected paths, and an activated cell monitoring unit. And a charging counter control unit that stops counting of the charging counter when it is detected that the activated cell does not arrive at a predetermined interval. Wherein the fixed-length cell switch attached interface unit. 32. When the alarm cell transmitting section detects that the activated cell has arrived again at a predetermined interval after the alarm cell is transmitted, the activated cell monitoring section detects the activated cell. The charging counter control unit is configured to stop sending of the alarm cell, and the charging counter control unit restarts counting of the charging counter when the sending of the alarm cell in the alarm cell sending unit is stopped. Is characterized by being
An interface device provided with a fixed length cell switch according to claim 31. 33. A concentrator for concentrating input / output information of a plurality of interface units attached to an input / output unit of an exchange switch unit of a fixed-length cell switch that handles fixed-length cells, wherein When a dedicated cell capturing unit that captures an own-station dedicated cell having identification information or routing information, and the own-station dedicated cell is captured by the dedicated-cell capturing unit, all routing information is added to the own-station dedicated cell, and the same applies. A concentrator with a fixed-length cell switch equipped with a cell conversion copying unit for copying a plurality of own-station-dedicated cells having the contents of. 34. An exchange switch unit having three or more switch stages, a main control unit for the exchange switch unit, and a plurality of interface units attached to an input / output unit of the exchange switch unit. As a result, in a fixed-length cell switch that handles fixed-length cells, when a failure occurs in the intermediate switch stage in the exchange switch unit, the intermediate switch stages are instructed to all interface units accommodated in the main control unit. Of the routing information of the intermediate switch stage, and the interface unit that has received the notification of the routing information of the intermediate switch stage sends an alarm cell to a path that matches the notified routing information. What to do when a failure occurs in a fixed length cell switch. 35. When the failure of the intermediate switch stage in the exchange switch unit is recovered, all the interface units accommodated in the main control unit are notified of that fact, and the interface which has received the notification. 35. The method for coping with a failure in a fixed length cell switch according to claim 34, characterized in that the sending of the alarm cell is stopped in the section. 36. The interface unit, which has received the notification of the routing information about the intermediate switch stage in the exchange switch unit, sends out the alarm cell to a path that matches the notified routing information,
Characterized by stopping the counting of the billing counter,
A method of coping with a failure in the fixed length cell exchange according to claim 35. 37. When the failure of the intermediate switch stage in the exchange switch section is recovered, a notification to that effect is sent to all the interface sections housed in the main control section, and the interface that has received the notification is sent. 37. The method for coping with a failure in a fixed-length cell switch according to claim 36, wherein the section stops sending of the alarm cell and restarts counting of the billing counter. 38. An exchange switch unit, a main control unit for the exchange switch unit, a plurality of interface units attached to the input / output unit of the exchange switch unit, and input / output information of the plurality of interface units. By providing a concentrating unit for concentrating lines, in a fixed-length cell switch that handles fixed-length cells, when the concentrating unit detects a failure in the interface unit, the concentrating unit indicates that it is an alarm cell. The cell to which the information is added is sent to the exchange switch unit, and when the cell to which the information indicating the alarm cell is added is received by another interface unit, the pseudo alarm cell is transmitted to the other interface unit. A method for dealing with a failure in a fixed-length cell switch, which is created and sent to the line side. 39. When the cell to which the information indicating that the alarm cell is added is received by another interface unit, the other interface unit creates the pseudo alarm cell and sends it to the line side. The method for coping with a failure in the fixed-length cell switch according to claim 38, characterized in that the counting of the billing counter is stopped. 40. An exchange switch unit, a main control unit for the exchange switch unit, a plurality of interface units attached to the input / output unit of the exchange switch unit, and input / output information of the plurality of interface units. In a fixed-length cell exchange that handles fixed-length cells by providing a concentrating unit for concentrating lines, the concentrating unit detects an interface unit failure detection unit that detects a failure in the interface unit, and the interface unit failure detection And a warning cell information sending unit for sending a cell to which information indicating that it is an alarm cell is sent to the exchange switch unit when the interface unit detects a fault in the interface unit, And an alarm cell information receiving unit that receives a cell to which information indicating that A fixed length cell switch, comprising a pseudo alarm cell creating unit for creating a pseudo alarm cell when receiving a cell to which information to the effect is added and transmitting the pseudo alarm cell to the line side. 41. The interface unit includes a billing counter, and when the alarm cell information receiving unit receives a cell to which information indicating that the alarm cell is added, the billing counter stops counting. The fixed length cell exchange according to claim 40, further comprising a counter controller. 42. In a fixed-length cell switch for handling fixed-length cells, the interface section prevents a failure of a line layer by providing a switching switch section and an interface section attached to an input / output section of the switching switch section. When detected,
A method of coping with a failure in a fixed-length cell switch, characterized in that the interface section stops counting of charging counters for all connections. 43. The fixed length cell according to claim 42, wherein when the interface unit detects the restoration of the faulty line layer, the interface unit restarts counting of the charging counter for all the connections. What to do when a failure occurs in the exchange. 44. In an interface device attached to an input / output unit of a switching switch unit of a fixed length cell switch for handling fixed length cells, a billing counter, a line layer failure detection unit for detecting a failure of a line layer, and the line layer. A fixed-length cell switch equipped with a charging counter control unit that stops counting of the charging counter for all connections when a failure in the line layer is detected by the failure detection unit. Interface device. 45. The billing counter control unit is configured to restart counting of the billing counter when the line layer fault detection unit detects restoration of the faulty line layer. An interface device attached to a fixed-length cell switch according to claim 44.