JP4023069B2 - ATM system and power-off detection method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ATM system that detects a power-off of an ATM terminator through a telecommunications carrier and a power-off detection method thereof.
[0002]
[Prior art]
B-ISDN (Broadband ISDN) is planned as a next-generation ISDN (Integrated Services Digital Network) to cope with future high-speed broadband information communication. In this B-ISDN, in addition to the current ISDN technology, ATM (Asynchronous Transfer Mode), optical fiber transmission and the like are used in order to efficiently transmit and exchange all communication information from low speed, high speed to super high speed. Three new technologies, SDH (Synchronous Digital Hierarchy), are adopted.
[0003]
B-ISDN is an ATM switch, an ATM cross-connect device, and an optical subscriber line terminator connected by optical fibers. Using this optical fiber as a transmission line, ATM cells as shown in FIG. To transmit.
[0004]
As shown in the figure, the ATM cell is a 53-byte fixed-length cell composed of a 5-byte header part and a 48-byte payload part.
[0005]
A line for transferring an ATM cell is selected by a VPI (Virtual Path Identifier) and a VCI (Virtual Channel Identifier) included in the header portion. A specific VCI field is used for OAM cell identification of the virtual path.
[0006]
PT (Payload Type) is a field that expresses the type of information in the payload part, and this makes it possible to identify cell-level forward congestion notifications, virtual channel OAM cells, and the like. CLP (Cell Loss Priority) is a field expressing the priority of cell loss control that may be performed when congestion or the like occurs.
[0007]
In addition, there are the following detection methods when the power supply of the subscriber termination device is shut off in the B-ISDN in which a telecommunications carrier is interposed in the relay section.
[0008]
When the subscriber termination device is powered off by the subscriber in use, the subscriber termination device sends a power-off bit to the communication line connected to the telecommunications carrier. A telecommunications carrier that detects a power-off bit from a subscriber termination device issues an alarm by sending all the main signals to 1 to the device that monitors the subscriber termination device.
[0009]
After that, when the interrupted power supply of the subscriber termination device is turned on again and returns to the normal state, the subscriber termination device sends a message indicating that the power supply is normal to the communication line connected to the telecommunications carrier. To do. The telecommunications carrier that has detected the recovery of the interrupted power supply normally recovers and transmits the main signal set to 1 to the in-house device that monitors the subscriber termination device.
[0010]
[Problems to be solved by the invention]
However, when a telecommunications carrier introducing a device that transmits a cell is interposed, if the power supply of the subscriber termination device is cut off, the telecommunications carrier is terminated.
[0011]
In addition, when the communication line connecting the subscriber termination device and the telecommunications carrier is out of order, the in-house device detects the subscriber termination device as a signal disconnection in the same manner as in the case of the power interruption described above. It is not possible to determine whether or not the power supply of the subscriber termination device is cut off.
[0012]
The subject of the present invention can be easily known in the in-house apparatus monitoring the subscriber termination device without affecting the device in the intervening telecommunications carrier without interrupting the power supply of the subscriber termination device. It is to construct an ATM system and its power-off detection method.
[0013]
[Means for Solving the Problems]
In order to solve the above problems, the invention described in claim 1
An ATM terminator (for example, ATM terminator 2 in FIG. 1) that sends out ATM cell signals;
A management device (for example, in-house device 4 in FIG. 1) that receives ATM cells transmitted from the ATM termination device;
A communication that is interposed between the ATM terminator and the management device and issues a warning to the management device when a power cut bit transmitted from the ATM terminator is detected when the power of the ATM terminator is shut off A carrier line (for example, telecommunications carrier 3 in FIG. 1);
ATM system (for example, ATM system 1 in FIG. 1),
When the power is shut off, the ATM terminator sends a power-off cell including information indicating power-off before sending the power-off bit.
The carrier line transfers the power-off cell transmitted from the ATM terminal device to the management device through the transmission line,
The management device detects power-off of the ATM termination device by detecting the power-off cell.
[0014]
The invention according to claim 5
An ATM terminator (for example, ATM terminator 2 in FIG. 1) that sends out ATM cell signals;
A management device (for example, in-house device 4 in FIG. 1) that receives ATM cells transmitted from the ATM termination device;
A communication that is interposed between the ATM terminator and the management device and issues a warning to the management device when a power cut bit transmitted from the ATM terminator is detected when the power of the ATM terminator is shut off A carrier line (for example, telecommunications carrier 3 in FIG. 1);
In the power failure detection method of an ATM system (for example, ATM system 1 in FIG. 1) composed of:
The ATM terminator, when the power is shut off, sends a power-off cell including information indicating power-off before sending the power-off bit (for example, S1 in FIG. 5);
The communication carrier line transmits a power-off cell transmitted from the ATM terminal device and transfers it to the management device (for example, S2 and S3 in FIG. 5). A detection step of detecting a power shutdown of the ATM termination device by detecting a cell;
Is further included.
[0015]
Therefore, when the power is cut off in the ATM terminator, the management device can easily detect the power-off of the ATM terminator by detecting the power-off cell transmitted from the ATM terminator.
[0016]
In addition, since the power-off cell transmitted from the ATM termination device is transmitted through the intervening communication carrier line, the management device can know that the ATM termination device is powered off without affecting the communication carrier line. it can.
[0017]
The invention according to claim 2 is the ATM system according to claim 1,
The ATM terminator generates and sends out the power-off cell by manipulating the header part of the ATM cell.
[0018]
According to a sixth aspect of the present invention, in the ATM system power-off detection method of the fifth aspect,
In the sending step, the ATM terminator generates and sends the power-off cell by operating a header part of the ATM cell.
[0019]
Therefore, an ATM address can be set by manipulating the header portion of the ATM cell, and the generated / transmitted power-off cell can be transmitted through the communication carrier line.
[0020]
The invention according to claim 3 is the ATM system according to claim 1,
The ATM terminator generates and transmits the power-off cell by setting power-off information in a payload part of the ATM cell.
[0021]
According to a seventh aspect of the present invention, in the method for detecting power interruption of the ATM system according to the sixth aspect,
In the sending step, the ATM terminator generates and sends the power-off cell by setting power-off information in a payload portion of the ATM cell.
[0022]
Therefore, the power-off cell can be easily generated and transmitted by manipulating the payload portion of the ATM cell.
[0023]
The invention according to claim 4 is the ATM system according to any one of claims 1 to 3,
When the management device detects a power-off of the ATM termination device, the management device invalidates a warning that is subsequently issued by the electric utility.
[0024]
Further, the invention according to claim 8 is the method for detecting power interruption of the ATM system according to any one of claims 5 to 7,
The management device further includes a warning invalidation step of invalidating a warning issued by the electric utility thereafter when the power interruption of the ATM termination device is detected.
[0025]
Therefore, since the alarm issued from the communication carrier line is invalidated by the power-off bit sent when the power supply of the ATM termination device is turned off, the management device can be easily managed without changing the configuration of the intervening communication carrier line. Can know that the ATM terminator is powered off.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments will be described in detail with reference to the drawings.
[0027]
First, the configuration will be described.
FIG. 1 shows a configuration of an ATM system 1 to which the present invention is applied.
This ATM system 1 is composed of an ATM termination device 2, a telecommunications carrier 3, and an in-house device 4. The ATM termination device 2 and the in-house device 4 that are subscriber termination devices intervene with the telecommunications carrier 3. Thus, they are connected by communication lines 5 and 6 each using an optical fiber as a transmission path. Various signals are exchanged via the communication lines 5 and 6.
[0028]
The in-house device 4 monitors the ATM termination device 2 and receives a signal from the ATM termination device 2.
[0029]
The ATM terminating device 2 sends a signal through the telecommunications carrier 3 and outputs an OAM cell as a power-off signal to the communication line 5 when the power is cut off by a subscriber or the like. Then, it shuts off its own power supply.
[0030]
FIG. 3 is a diagram showing an internal configuration of the ATM terminator 2 that sends out the power-off cell. In the figure, a header setting unit 21 arbitrarily sets a header value of an OAM cell 22 to be a power-off cell, and an OAM cell insertion unit 23 performs the above OAM cell when the power of the ATM terminator 2 is cut off. 22 is sent out.
[0031]
The header calculation unit 24 inserts the calculated result into the header portion of the sent ATM cell. That is, by manipulating the VPI and VCI fields in the header part, a line for transfer can be selected, the intervening telecommunications carrier 3 can be transmitted, and the OAM cell can be transferred to the in-station device 4. Further, by manipulating the VCI and PT fields, the ATM cell is set as an alarm transfer OAM cell.
[0032]
The path setting unit 25 sets the path state of the ATM cell signal to be transmitted in order to correspond to PDH (6M) which is the signal multiplexing method adopted, and the frame setting unit 26 sets the synchronization state of the multiframe. Set.
[0033]
The control unit 28 controls the alarm transmission when the power of the ATM terminating device 2 is shut down. When the power shutoff is detected, the control unit 28 instructs the devices of the OAM cell insertion unit 23, the path setting unit 25, and the frame setting unit 26. give.
The photoelectric conversion unit 27 is an apparatus that converts an electric signal into an optical signal so that an input signal corresponds to an optical fiber transmission line that is a communication line.
[0034]
FIG. 4 is a diagram showing an internal configuration of the in-house station apparatus 4.
In the figure, an input signal is converted from an optical signal into an electrical signal corresponding to the in-house apparatus 4 in the photoelectric conversion unit 41.
[0035]
The OAM cell detection unit 44 detects an OAM cell (power-off cell) from the received ATM cell signal. Further, the frame detection unit 42 establishes synchronization of the received multi-frame of the power-off cell, and the path detection unit 43 establishes the PDH path state. Each of these units is controlled by the control unit 45.
[0036]
Next, the operation will be described.
The operation of the ATM system 1 when the power supply of the ATM terminating device 2 is cut off will be described with reference to FIG.
[0037]
First, in the ATM termination device 2, when the power is cut off by the subscriber, the control unit 28 in the ATM termination device 2 issues instructions to the OAM cell insertion unit 23, the path setting unit 25, and the frame setting unit 26. Then, the OAM cell set as the power-off ATM cell is transmitted (step S1).
[0038]
The power-off ATM cell sent from the ATM terminal device 2 is transmitted through the telecommunications carrier 3 (step S2) and transferred to the in-house device 4 (step S3).
[0039]
When the power-off cell is detected by the OAM cell detection unit 44 in the in-house device 4, the in-house device 4 transmits an alarm to other devices, notifying that the line is unusable and alarming. Issue is prohibited, and warnings that are detected thereafter are disabled.
[0040]
Also, the ATM terminator 2 that has sent out the power-off ATM cell sends a power-off bit to the telecommunications carrier 3 as before, before the power is cut off (step S4). The telecommunications carrier 3 that has detected the power cut bit issues an alarm by setting all the main signals being transmitted to 1 and transmitting them to the in-house device 4 (steps S5 and S6).
[0041]
However, in this case, since the in-house apparatus 4 is in a state in which an alarm is not issued, the alarm from the telecommunications carrier 3 due to the power interruption is not valid.
[0042]
Thereafter, when the power is restored in the ATM terminating device 2, the power restoration is sent to the telecommunications carrier 3 (step S7). Is returned to normal and transmitted to the in-house apparatus 4 (steps S8 and S9).
[0043]
The in-house device 4 that has detected the recovered main signal cancels the invalidated alarm and returns it to normal.
[0044]
As described above, when power is cut off in the ATM terminator 2, if the ATM cell is issued from the ATM terminator 2, the ATM cell passes through the electric power carrier device. It is possible to easily detect the power interruption of the ATM terminating device 2 by the in-house station device 4 without affecting the business operator 3.
[0045]
In this embodiment, the power-off ATM cell is generated by manipulating the bit value of the header portion of the ATM cell. However, the power-off ATM cell is set by setting the power-off information in the payload portion of the ATM cell. May be configured to be generated and transmitted.
[0046]
【The invention's effect】
According to the first or fifth aspect of the present invention, when the power is cut off in the ATM termination device, the management device can easily detect the ATM termination by detecting the power-off cell transmitted from the ATM termination device. It is possible to detect a power failure of the device.
[0047]
In addition, since the power-off cell transmitted from the ATM termination device is transmitted through the intervening communication carrier line, the management device can know that the ATM termination device is powered off without affecting the communication carrier line. it can.
[0048]
According to the invention described in claim 2 or 6, in addition to the effect of the invention described in claim 1 or 5, the power-off cell is generated and transmitted by setting the ATM address by operating the header part of the ATM cell. Can be transmitted through the communication carrier line.
[0049]
According to the invention described in claim 3 or 7, in addition to the effect of the invention described in claim 1 or 5, a power-off cell can be easily generated and transmitted by manipulating the payload portion of the ATM cell.
[0050]
According to the invention described in claim 4 or 8, in addition to the effect of the invention described in claim 1, 2, 3, 5, 6 or 7, the power cut-off bit transmitted when the power of the ATM terminator is turned off. Since the alarm issued from the telecommunications carrier line is invalidated, the management device can easily know the power interruption of the ATM termination device without changing the configuration of the intervening telecommunications carrier line.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of an ATM system to which the present invention is applied.
FIG. 2 is a diagram showing an ATM cell format (UNI).
FIG. 3 is a diagram showing an internal configuration of the ATM terminator 2;
FIG. 4 is a diagram showing an internal configuration of the in-house station apparatus 4;
FIG. 5 is a diagram showing an operation flow of the ATM system.
[Explanation of symbols]
1 ATM system 2 ATM terminator 3 Telecommunications carrier 4 In-house equipment 5 and 6 Communication line

Claims (8)

An ATM terminator for sending out ATM cell signals;
A management device for receiving an ATM cell transmitted from the ATM termination device;
A communication that is interposed between the ATM terminator and the management device and issues a warning to the management device when a power cut bit transmitted from the ATM terminator is detected when the power of the ATM terminator is shut off With operator lines,
ATM system consisting of
When the power is shut off, the ATM terminator sends a power-off cell including information indicating power-off before sending the power-off bit.
The carrier line transfers the power-off cell transmitted from the ATM terminal device to the management device through the transmission line,
The ATM system is characterized in that the management device detects power-off of the ATM termination device by detecting the power-off cell. 2. The ATM system according to claim 1, wherein the ATM termination device generates and transmits the power-off cell by operating a header portion of the ATM cell. 2. The ATM system according to claim 1, wherein the ATM terminator generates and transmits the power-off cell by setting power-off information in a payload portion of the ATM cell. 4. The ATM system according to claim 1, wherein when the management device detects a power-off of the ATM termination device, the management device invalidates an alarm that is subsequently issued by the electric utility. 5. An ATM terminator for sending out ATM cell signals;
A management device for receiving an ATM cell transmitted from the ATM termination device;
A communication that is interposed between the ATM terminator and the management device and issues a warning to the management device when a power cut bit transmitted from the ATM terminator is detected when the power of the ATM terminator is shut off With operator lines,
In a method for detecting power interruption of an ATM system comprising:
The ATM terminating device, when the power is shut off, prior to sending the power shut-off bit, sending out a power-off cell including information indicating power-off,
The communication carrier line is configured to transmit a power-off cell transmitted from the ATM termination device and transfer it to the management device;
The management device detects a power cutoff of the ATM termination device by detecting the power cutoff cell; and
A method for detecting power interruption of an ATM system, further comprising: 6. The method of claim 5, wherein in the sending step, the ATM terminator generates and sends the power-off cell by operating a header part of the ATM cell. 6. The ATM system power-off of the ATM system according to claim 5, wherein, in the sending step, the ATM termination device generates and sends the power-off cell by setting power-off information in a payload portion of the ATM cell. Detection method. The said management apparatus further includes the alarm invalidation process which invalidates the alarm which the said electric power provider issues after that when the power failure of the said ATM termination device is detected. ATM system power failure detection method.

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