JP3341703B2 - Communication protection method and apparatus in packet communication - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication protection method and apparatus for packet communication, and more particularly, to an asynchronous transfer mode (asynchronous transfer mode).
The present invention relates to a communication protection method and apparatus in packet communication using an r mode (ATM) communication apparatus.

[0002]

2. Description of the Related Art Conventionally, when protecting a connection for packet communication, a 1 + 1 method of securing two working and protection connections has been adopted. As such a device, for example, a packet connection system switching method and an asynchronous communication mode communication device disclosed in JP-A-10-145374 are known.

FIG. 12 is a block diagram of the conventional asynchronous transfer mode communication apparatus having the system switching of the packet connection. As shown in FIG. 12, the asynchronous transfer mode communication device comprises an ATM communication device 1 and an ATM communication device 2
During the working VC (effective connection) 10-
0 and the VC 10-1 and the ATM communication device 1 on the transmission side.
At -1, the user cell is transmitted only to the active VC.

In the ATM communication device 1-2 on the receiving side, a connection is set so that both the cells of the working VC and the cells of the protection VC can be transmitted downstream. When a failure occurs, only the ATM communication device on the transmitting side changes the cell transmission destination to the working or protection VC, thereby completing the switching.

[0005]

However, in this prior art, it is always necessary to prepare working and protection VCs. This means that when n VCs are used for communication in the network, at least n protection VCs exist.

That is, these protection VCs are:
If a failure has not occurred in the communication path, an area for identifying the VC in the network is wasted. In a network in which a VC is dynamically set, each device always performs a VC setting process twice as much as that required for communication.

Further, the protection VC is prepared irrespective of the current use state. For this reason, once a protection VC is set, the protection VC remains unchanged even if no packet flows on the working side.

An object of the present invention is to provide a communication protection method and apparatus in packet communication that can reduce the load of connection setting processing of a communication apparatus in a network that dynamically generates connections while suppressing waste of connection resources. It is to be.

[0009]

In order to achieve the above object, a communication protection method in packet communication according to the present invention provides a method for protecting a communication connection for packet communication using an asynchronous transfer mode communication device. In the communication protection method, the used bandwidth of the used communication connection is measured, and this measurement result is compared with a certain threshold.
If it is detected that the number exceeds the threshold value, a process of establishing a communication connection on the standby side is performed.

[0010] With the above configuration, in a communication protection method in packet communication for protecting a communication connection for packet communication using an asynchronous transfer mode communication device, a bandwidth used for a communication connection used is measured , If this measurement is compared to a certain threshold
If the connection is detected, a process of establishing a communication connection on the standby side is performed. As a result, it is possible to reduce the load of the connection setting process of the communication device in the network that dynamically generates the connection while suppressing the waste of the connection resources.

Further, with the communication protection apparatus for packet communication according to the present invention, the communication protection method for packet communication can be realized.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a configuration of a communication protection device in packet communication according to an embodiment of the present invention.

As shown in FIG. 1, a communication protection device 10 in packet communication includes three packet processing units 11, 1
2, 13, an ATM switch 14, two ATM transmission line processing units 15, 16, a standby-side setting activation unit 17, and a path management unit 1.
8, virtual path identifier (virtual path id)
entity: VPI) / virtual channel identifier (v
actual channel identity
r: VCI) determination unit 19 and a switch management unit 20.

Each of the ATM transmission path processing units 15, 16
Has a band monitoring unit 21 and a cell demultiplexing unit 22. The illustration of the ATM transmission path processing unit 16 is omitted.

The communication protection device 1 in this packet communication
0 denotes three packet transmission lines 23, 24, 25 connected to the packet processing units 11, 12, 13 and two ATM transmission lines connected to the ATM transmission line processing units 15, 16, respectively. 26 and 27. And
IP arriving from each packet transmission path 23, 24, 25
(Internet protocol) packet.
It is converted into an ATM cell and transmitted to the destination IP address.

The packet processing unit 11 includes a packet transmission path 2
If the IP address information of the packet arriving from No. 3 is new, an operation-side setting request is output to the route management unit 18, and if known, it is converted into an ATM cell as it is and output to the ATM switch 14.

The packet processing unit 12 includes a packet transmission path 2
4 performs the same operation as that of the packet processing unit 11, and the packet processing unit 13 performs the same operation as the packet processing unit 11 of the packet that arrives from the packet transmission path 25.

The ATM cell switch 14 stores the ATM cells from the packet processing units 11, 12, and 13 in accordance with the header information and the switch table held by the switch management unit 19 or the ATM transmission line processing unit 15 or the ATM transmission line. Output to the processing unit 16. At the same time as the output, the ATM cell header is rewritten.

The ATM transmission line processing unit 15 monitors the band used for each cell header information in the ATM cell flow from the ATM cell switch 14, and, together with the ATM cell and the VPI
/ VCI multiplexed with the VPI / VCI determination cell from the VCI determination unit 19 and output to the ATM transmission line 26. At the same time as the output, VP of the ATM cells from the ATM transmission line 26 is output.
The I / VCI determination cell is output to the VPI / VCI determination unit 19.

The ATM transmission line processing unit 16 performs the same operation as the ATM transmission line processing unit 15 on the ATM transmission line 27.

The protection-side setting activation unit 17 compares the used bandwidth information for each connection from the ATM transmission line processing unit 15 and the ATM transmission line processing unit 16 with a protection-side setting threshold (threshold). The backup side setting request is output to the route management unit 18 for the ATM connection.

The route management unit 18 is provided for each packet processing unit 1
When an operation side request from the standby side, or a standby side request from the standby side setting activation section 17, is received, a corresponding output side port is selected from an internal routing table, and a VPI / VCI assignment of the port is requested. I do. That is, a port on which a backup connection can be set is selected, and a VPI / VCI determination request is output.

When there is a VPI / VCI assignment request from the route management unit 18, the VPI / VCI determining unit 19 determines a VPI / VCI to be used for the backup connection according to a predetermined procedure and data format. VPI / VCI request cell or VPI / VCI between adjacent devices
It performs transmission and reception of assigned cells.

The switch management unit 20 determines an input-side VPI / VCI value to be paired with the output-side VPI / VCI value obtained by the VPI / VCI determination unit 19, creates a switch table, and assigns a switch table to the input-side port. The input side information is transmitted to any of the corresponding packet processing units 11, 12, and 13.

That is, the result obtained by the VPI / VCI decision unit 19 is registered in the switch table as a protection side connection, and if any failure occurs on the working side, the working side connection information is discarded and the protection side connection information is discarded. By using the side connection information, communication protection is realized.

Therefore, according to the communication protection apparatus 10 in the packet communication according to the present invention, the protection side connection is secured for the connection having a large used band, and the influence upon the occurrence of a failure can be secured while securing the economy of the network. Communication of large users can be protected.

The bandwidth monitoring unit 21 of each of the ATM transmission line processing units 15 and 16 is provided for each ATM transmission line.
It monitors the header of the passing ATM cell and measures the bandwidth used for each connection.

Next, the operation of the communication protection device 10 in packet communication will be described.

FIG. 2 is an explanatory diagram of a packet table held inside the packet processing unit of FIG. FIG. 3 is an explanatory diagram of a switch table held by the switch management unit in FIG.

The packet processing unit 11 stores therein a packet table shown in FIG.
Each time a packet arrives at the packet table, it is checked whether the destination IP address exists in the entry of this packet table.

If it does not exist, the operation side setting request for the destination IP address is output to the route management unit 18. If it does exist, the VPI / VCI written in the entry is output.
The packet is decomposed into an ATM cell format using the ATM cell header as an ATM cell header, and output to the ATM cell switch 14.

The packet processing section 12 is connected to the packet transmission path 24, and the packet processing section 13 is connected to the packet transmission path 2
5 perform the same operation as the packet processing unit 11.

At normal times, the ATM cell switch 14 refers to the header information of the ATM cells arriving from each of the packet processing units 11, 12, and 13, and refers to the switch table (see FIG. 3) held by the switch management unit 20. Those that do not exist in the operation entry are discarded, and those that do exist rewrite the header information to the output side VPI value and output side VCI value of the entry and output it to the output side port indicated in the entry.

When the ATM cell switch 14 finds out that some failure has occurred in the output transmission line, the ATM cell switch 14 uses the output transmission line in the operation side entry of the switch table (see FIG. 3). Delete things, and
If the IP address of the deleted entry exists in the backup entry, the entry is stored again as the working entry, and the operation returns to the normal operation.

In the ATM transmission line processing unit 15, the bandwidth monitoring unit 21 monitors the ATM cells arriving from the ATM switch 14, and counts the number of cells arriving per unit time for each header information. Is output to the backup-side setting activation unit 17 as used band information, and the received ATM cell is directly used as the cell demultiplexing unit 22.
Output to

The cell multiplexing / demultiplexing unit 22 receives the ATM cell from the band monitoring unit 21 and the VPI / VCI
The PI / VCI request cell and the VPI / VCI assigned cell are multiplexed and output to the ATM transmission line 26,
VPI / VCI request cell and VP among ATM cells from
Only I / VCI assigned cells are taken out and VPI / VCI
Output to the determination unit 19.

The transmission and reception of the VPI / VCI request cell and the VPI / VCI assigned cell are performed by the VPI / VCI
= 0/32 must be used, and the format of these request cells follows the cell format shown in FIG.

The ATM transmission line processing unit 16 performs the same operation on the ATM transmission line 27 as the ATM transmission line processing unit 15.

The protection-side setting activation section 17 is provided with the band monitoring sections 2 of the ATM transmission path processing section 15 and the ATM transmission path processing section 16.
The number of cells per unit time for each piece of header information received from No. 1 is compared with a protection-side setting threshold. If the threshold is exceeded, the output port, output VPI value, output VCI value, and destination The backup side setting request specifying the IP address is output to the route management unit 18.

The route management unit 18 has therein a route table of the format shown in FIG. This routing table is
9 is a table in which, for a destination IP address, a port identifier used as an operation side output and a port identifier used as a backup side output are registered.

When the route management unit 18 receives an operation side setting request from any of the packet processing units 11, 12, and 13, it searches the route table for the IP address displayed in the request, The operation side port information inside is taken out as an output port.

Then, when a backup setting request arrives from the backup setting activation unit 17, the IP address displayed in the request is searched from this routing table, and the backup port information in the entry is taken out as an output port. .

The route management unit 18 sends the VPI / VCI assignment request specifying the output port, the setting request type (operating side or standby side), and the destination IP address to the VPI / VCI.
Output to CI determination unit 19.

When the VPI / VCI determination unit 19 receives the VPI / VCI assignment request from the route management unit 18,
First, it is checked whether the same entry as the set of the setting request type and the destination IP address exists in the switch table (see FIG. 3) in the switch management unit 20.

If the same entry is not found in the switch table regardless of the type of the setting request regardless of the operation side or the standby side, the requested IP address value is inserted into the VPI / VCI request cell (see FIG. 4). A of requested port
Output to the cell demultiplexing unit 22 of the TM transmission path processing unit (either 15 or 16).

In an adjacent communication device of the same type that has received this VPI / VCI request cell, an unused VPI / VCI value is inserted into a VPI / VCI assigned cell and transmitted according to, for example, the procedure shown in FIG. Shall be.

The VPI / VCI determining unit 19 determines whether the transmitted V
When a VPI / VCI assigned cell having the same IP address value as the IP address inserted in the PI / VCI request cell is received from the same port, the VPI / VCI value is taken out and the setting request type and the destination IP address are switched. Output to the management unit 19.

If the setting request type is the operation side and the destination IP address already exists in the operation side entry of the switch table, the output side port and the output side VPI of the entry are set.
And the output side VCI to the switch management unit 20. If the setting request type is the protection side and the destination IP address already exists in the protection side entry of the switch table, nothing is performed.

The VPI / VCI determining unit 19 determines whether the AT
When a VPI / VCI request cell is received from the cell demultiplexing unit 22 of the M transmission line processing unit 15 or the ATM transmission line processing unit 16, the switch table in the switch management unit 20 is referred to according to the procedure of FIG. Search for unused VPI / VCI values at the port where the
It outputs the I / VCI assigned cell to the port where the VPI / VCI request cell was received.

The switch management unit 20 responds to the working-side setting request transferred from the VPI / VCI determination unit 19 by using the unused VPI / VC among the requesting input ports.
I is searched from the switch table, and together with the output side port, the output side VPI and the output side VCI acquired by the VPI / VCI determination unit 19 from the adjacent device, the [destination IP address, input side port] , Input side VPI, input side VCI, output side port, output side VPI, output side VCI] are registered as one entry.

Further, the switch management unit 20 is provided with a VPI / V
In response to the protection-side setting request transferred from the CI determination unit 19, all of the working-side entries having the same IP address are searched from the switch table, and the input side port, the input side VPI, and the input side VCI are extracted. , Their values and the output port from the VPI / VCI determination unit 19,
Along with the output side VPI and the output side VCI, [Destination IP address, input side port, input side VPI, input side VCI, output side port, output side VPI, output side VCI] is set to 1 in the spare side entry of the switch table. Register as one entry.

By these operations, the communication protection device 1
When the used band of the ATM cell passing through 0 exceeds the protection side setting threshold, a protection side entry different from the operation side entry is stored in the switch table for the connection.

This spare side entry is used as the operation side entry when any failure occurs in the ATM transmission line used as the operation side. In other words, a connection on the protection side is secured for this connection, and communication service can be provided continuously even when a failure occurs on the working side.

FIG. 7 is a block diagram showing an example of a network configuration using the communication protection device of FIG. In FIG.
The communication device A and the communication device B are communication protection devices 10 (see FIG. 1) for packet communication.
The transmission lines 26 and the ATM transmission lines 27 are connected.

The communication terminal a1 is connected to the packet transmission line 23 of the communication device A, the communication terminal a2 is connected to the packet transmission line 24, and the communication terminal a3 is connected to the packet transmission line 25. Packet transmission path 23 of device B
Is connected to a communication terminal b.

Thereafter, in the configuration of FIG.
1. Consider an operation of starting communication to the communication terminal b in the order of the communication terminal a2 and the communication terminal a3. Note that the bandwidth used by each communication terminal is 2 Mbps, and the protection-side setting threshold is 5 Mbps. Also, the route table of the route management unit 18 of the communication device A is assumed to be as shown in FIG. 8 by the initial setting, but all other tables are empty.

The communication terminal a1 outputs a packet addressed to the communication terminal b to the packet transmission path 23. Since the packet table of the packet processing unit 11 is empty, the communication device A outputs an operation-side setting request addressed to the IP address b to the route management unit 18.

The route management unit 18 refers to the route table and sets the ATM transmission line 26 as the operation side route for the IP address b.
Is selected, and a VPI / VCI allocation request for the operation side setting to the IP address b and the ATM transmission line 26 is sent to the VPI / V
Output to CI determination unit 19.

The VPI / VCI determination unit 19
Upon receiving the / VCI assignment request, a VPI / VCI request cell in the format shown in FIG. 4 is created, and its IP address field value is set to b. When this cell is output to the cell demultiplexing unit 22 of the ATM transmission line processing unit 15, another ATM
The data is multiplexed with the cell and output to the ATM transmission line 26.

The communication device B receives the VPI / VCI request cell transmitted from the communication device A from the ATM transmission line 26, extracts the cell by the cell demultiplexing section 22, and then outputs the VPI / VCI request cell.
Output to CI determination unit 19. VPI / VCI determination unit 19
Is the ATM transmission line 2 on which the VPI / VCI request cell has arrived.
In step 6, unused VPI = 1 and VCI = 32 are selected, and VPI = 0 and VCI = 33 are selected as the output side.

Therefore, the working side entry of the switch table of the switch management unit 20 includes [IP address, input side port, input side VPI, input side VCI, output side port,
Output side VPI, input side VCI] = [b, ATM transmission line 2
6, 1, 32, packet transmission paths 23, 0, 33] are registered.

At the same time, the VPI / VCI determination unit 19 of the communication device B makes the VPI / VC determination according to the format shown in FIG.
Create an I-allocated cell, IP address b, VPI / VCI =
1/32 is inserted and output to the cell multiplexing / demultiplexing unit 22 of the ATM transmission line processing unit 15 so as to be transmitted to the ATM transmission line 26.

The communication device A receives the VPI / VCI assigned cell transmitted from the communication device B from the ATM transmission line 26 and outputs the cell to the VPI / VCI determination unit 19. VPI / V
The CI determination unit 19 determines whether the VPI / VCI /
It recognizes that VPI / VCI = 1/32 is used from the VCI field, and transmits the value to the switch management unit 20.

The switch management unit 20 outputs VPI / VCI = 1/32 received from the VPI / VCI determination unit 19.
Is selected on the packet transmission path 23 as VPI / VCI = 1/33. By this operation, the working-side entry in the switch table of the switch management unit 20 includes [IP address, input port, input V
PI, input VCI, output port, output VPI, input VCI] = [b, packet transmission paths 23, 1, 33,
ATM transmission lines 26, 1, 32] are registered.

By the above operation, as shown in FIG. 9, the packet from the communication terminal a1 to the communication terminal b is transmitted to the communication device A.
Is output to the ATM transmission line 26 at VPI / VCI = 1/32. In the communication device B, all of those cells are transmitted to the communication terminal b.
Output to

Thereafter, when a packet arrives from the communication terminal a2 to the communication terminal b, the communication device A similarly sends a similar request to the route management unit 18 and the VPI / VCI determination unit 19.

However, since the switch table of the switch management unit 20 already has an entry for the ATM transmission line 26 which is the current setting of the IP address b, the unused VPI in the packet transmission line 24 is used as the input side. / V
CI = 0/33 is selected, and the working-side entry of the switch table contains [IP address, input port, input V
PI, input side VCI, output side port, output side VPI, input side VCI] = [b, packet transmission paths 24, 0, 33,
ATM transmission lines 26, 1, 32] are registered.

By this operation, as shown in FIG. 10, the communication apparatus A sets both the packet from the communication terminal a1 to the communication terminal b and the packet from the communication terminal a2 to the communication terminal b to the VPI / VCI = Output to 1/32.

At this time, the bandwidth monitoring unit 21 of the ATM transmission line processing unit 15 of the communication device A determines that VPI / VCI = 1/32.
Has detected that the bandwidth used is 4 Mbps,
The protection-side setting activation unit 17 does not output a protection-side setting request because this connection does not exceed the protection-side setting threshold.

Similarly, after this, when starting the packet transmission from the communication terminal a3 to the communication terminal b, [IP address, input side port, input side VPI, input side VCI, output side port, output side VPI, input side VCI] = [b, packet transmission paths 25, 1, 33, ATM transmission paths 26, 1, 32] are registered, and as shown in FIG.
All packets from a3 to the communication terminal b are multiplexed to VPI / VCI = 1/32 of the ATM transmission line 26.

Here, when the communication terminal a3 starts communication with the terminal b, the bandwidth monitoring unit 21 of the ATM transmission line processing unit 15 of the communication device A has changed the used bandwidth of VPI / VCI = 1/32 to 6 Mbps. This is notified to the backup setting start-up unit 17.

The protection setting starter 17 sets the protection setting threshold of 5 Mbps to the VPI / A
Since VCI = 1/32 has been exceeded, a preliminary setting request for the IP address b is output to the route management unit 18.

The route management unit 18 receives the IP address from the route table.
The ATM transmission line 27 is selected as a spare port of the address b, and a VPI / VCI assignment request is output to the VPI / VCI determination unit 19.

In the VPI / VCI determination unit 19,
Outputs a VPI / VCI request cell to the ATM transmission line 27,
The VPI / VCI from the VPI / VCI determination unit 19 of the communication device B
It is assumed that a VPI / VCI assigned cell in which VCI = 1/32 is inserted is received.

Then, in the switch table of the switch management unit 20 of the communication device A, as a reserve entry,
[IP address, input side port, input side VPI, input side VCI, output side port, output side VPI, input side VCI]
= [B, packet transmission paths 23, 1, 33, ATM transmission paths 27, 1, 32], [b, packet transmission paths 24, 0, 3
3, ATM transmission paths 27, 1, 32] and [b, packet transmission paths 25, 1, 33, and ATM transmission paths 26, 1, 32] are registered.

By these operations, a backup connection is prepared for a connection whose use band exceeds the backup setting threshold 5 Mbps, and a backup connection is not prepared for a connection whose bandwidth does not exceed 5 Mbps.

For this reason, even if a failure occurs in a transmission line used only for important connections exceeding the protection-side setting threshold, service can be continued by using the protection-side connection. it can.

Therefore, the communication protection apparatus 10 in packet communication according to the present invention measures each used band for all the connections used in the line, compares the measured used band with the protection-side set threshold, For a connection whose measured bandwidth exceeds the threshold, a mechanism is provided for determining a connection identifier to be used by negotiation between the own device and an adjacent device and securing a spare connection.

As a result, a connection on the backup side is set for a connection having a wide band used.
This means that a connection on the backup side is preferentially set for a connection with a wide bandwidth, that is, a connection in which a large amount of information is lost when communication is interrupted due to a failure or the like. The service will be protected.

Further, a connection on the spare side is not set for a connection having a narrow band of use, that is, a connection having a small amount of information lost even when communication is interrupted due to a failure or the like. Connection identifiers, etc.) are saved. This means that in networks that dynamically set up connections,
This means that the load of the connection setting process of the communication device is reduced.

As described above, according to the present invention, the used bandwidth of the communication connection being used is measured, and when it is detected that the bandwidth exceeds the threshold, it is determined that the communication connection on the spare side Start the establishment process. Further, the processing for establishing a communication connection on the protection side further includes a function of establishing a protection connection in cooperation with the adjacent device, and when a failure occurs in the working connection, switching to the established protection connection is performed. It also has functions.

Accordingly, for a connection for packet communication that uses a wide band, a working connection and a protection connection are prepared, and for a connection that uses a narrow band, a protection connection is not set.
Waste of connection resources is suppressed.

Further, the total number of connections existing in the network is reduced as compared with the method of setting the protection side connection for all the working side connections. The load of the setting process can be reduced.

That is, conventionally, the connection of the standby system is fixedly set and secured, and the switching is performed at the time of failure or the like. However, in the communication protection method in packet communication according to the present invention,
Since a backup connection can be dynamically set at the communication device level according to the traffic capacity, resources (connection resources) in the communication device can be effectively used.

[0086]

As described above, according to the present invention, a communication connection used in a packet communication communication protection method for protecting a communication connection for packet communication using an asynchronous transfer mode communication device is used. Measurement of the bandwidth used, and compare this measurement result with a certain threshold.
If it is detected that the number of connections is larger than the threshold value , the communication connection on the backup side is established. Therefore, the waste of the connection resources is suppressed, and the load of the connection setting processing of the communication device in the network that dynamically generates the connection is reduced. Can be reduced.

Further, the communication protection method in packet communication can be realized by the communication protection device in packet communication according to the present invention.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a communication protection device in packet communication according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a packet table held inside a packet processing unit of FIG. 1;

FIG. 3 is an explanatory diagram of a switch table held by a switch management unit in FIG. 1;

FIG. 4 is an explanatory diagram of a cell format in transmitting and receiving a VPI / VCI request cell and a VPI / VCI assigned cell.

FIG. 5 is an explanatory diagram of a route table included in the route management unit.

FIG. 6 is an explanatory diagram showing a procedure for transmitting an unused VPI / VCI value.

FIG. 7 is a block diagram illustrating a network configuration example using the communication protection device of FIG. 1;

8 is an explanatory diagram illustrating a route table setting state of a route management unit in the communication device A of FIG. 7;

FIG. 9 is a block diagram (part 1) similar to the entry registration diagram and FIG. 7;

FIG. 10 is a block diagram (part 2) similar to the entry registration diagram and FIG. 7;

11 is an entry registration diagram and a block diagram similar to FIG. 7 (part 3). FIG.

FIG. 12 is a block diagram of a conventional asynchronous transfer mode communication device having a system switching of a packet connection.

[Explanation of symbols]

 Reference Signs List 10 Communication protection device in packet communication 11, 12, 13 Packet processing unit 14 ATM switch 15, 16 ATM transmission line processing unit 17 Reserve setting start unit 18 Route management unit 19 VPI / VCI determination unit 20 Switch management unit 21 Band monitoring unit 22 Cell demultiplexing unit 23, 24, 25 Packet transmission line 26, 27 ATM transmission line A, B Communication device a1, a2, a3, b Communication terminal

Claims (10)

(57) [Claims] In a communication protection method for packet communication for protecting a communication connection for packet communication using an asynchronous transfer mode communication device, a band used by a used communication connection is measured, and the measurement result is obtained. Compared to the threshold value
A communication protection method for packet communication, wherein a protection communication connection establishment process is performed when the communication is issued . 2. The communication protection method in packet communication according to claim 1 , wherein said establishing process is performed in cooperation with adjacent devices. 3. The communication protection method in packet communication according to claim 2 , wherein when a failure occurs in the working connection, the connection is switched to the established protection connection. 4. A communication protection device in packet communication for protecting a communication connection for packet communication using an asynchronous transfer mode communication device, wherein a protection side is determined based on a result of measuring a bandwidth used by a communication connection being used. an asynchronous transfer mode transmission line processing means for performing processing of establishing a communication connection with, monitors the header of an asynchronous transfer mode cell each connection
Used bandwidth information and the threshold set on the backup side
To output a standby-side setting request based on the comparison result.
The device-side setting activation unit and the operation side request or the backup side request from the packet processing unit.
When receiving, a port that can set up a backup connection
The virtual path identifier / virtual channel identifier
A communication protection device for packet communication , comprising: a route management unit that outputs a request . 5. The packet communication system according to claim 4 , further comprising a switching unit that performs the establishment process in cooperation with an adjacent device, and switches to an established standby connection when a failure occurs in a working connection. Communication protection device in. 6. An asynchronous transfer mode transmission line processing means, provided for each asynchronous transfer mode transmission line, for monitoring a header of a passing asynchronous transfer mode cell and measuring a used band for each connection; Multiplexing the asynchronous transfer mode cell from the bandwidth monitoring unit with the virtual path identifier / virtual channel identifier request cell or the virtual path identifier / virtual channel identifier assigned cell and outputting the multiplexed cell to the asynchronous transfer mode transmission line; A cell demultiplexing unit for extracting only the virtual path identifier / virtual channel identifier request cell or the virtual path identifier / virtual channel identifier assigned cell from among the asynchronous transfer mode cells from the asynchronous transfer mode transmission path. The communication protection device in packet communication according to claim 4 or 5 . 7. A communication protection device for packet communication which protects a communication connection for packet communication using an asynchronous transfer mode communication device, measures a used bandwidth of a used communication connection, and obtains a measurement result. A communication protection apparatus for packet communication, comprising: an asynchronous transfer mode transmission path processing unit that performs processing for establishing a communication connection on a standby side when detecting that the value exceeds a threshold value. 8. The packet according to claim 7, further comprising switching means for performing the establishment process in cooperation with adjacent devices and switching to the established standby connection when a failure occurs in the working connection. Communication protection device in communication. 9. A protection setting starter for monitoring a header of an asynchronous transfer mode cell, comparing used bandwidth information for each connection with a protection setting threshold, and outputting a protection setting request based on the comparison result. A path management unit that selects a port on which a backup connection can be set and outputs a virtual path identifier / virtual channel identifier determination request when receiving an operation request or the backup request from the processing unit. 9. The communication protection device in packet communication according to claim 7, wherein: 10. An asynchronous transfer mode transmission line processing means, provided for each asynchronous transfer mode transmission line, for monitoring a header of an asynchronous transfer mode cell passing therethrough and measuring a bandwidth used for each connection; Multiplexing the asynchronous transfer mode cell from the bandwidth monitoring unit with the virtual path identifier / virtual channel identifier request cell or the virtual path identifier / virtual channel identifier assigned cell and outputting the multiplexed cell to the asynchronous transfer mode transmission line; A cell demultiplexing unit for extracting only the virtual path identifier / virtual channel identifier request cell or the virtual path identifier / virtual channel identifier assigned cell from among the asynchronous transfer mode cells from the asynchronous transfer mode transmission path. The communication protection device in packet communication according to claim 9.