JPH06223016A - Communication line switching device and communication line switching method using the same - Google Patents

Abstract

PURPOSE:To use an inexpensive replacing line with an alternate path if a direct line is troubled without altering computer-side software and hardware. CONSTITUTION:A switching part 20 switches a computer 71 to the side of the direct line 80 or replacing line 110. An interface conversion part 60 matches the physical interface of the direct line 80 with that of the replacing line 110. An operation/display part 30 instructs which of the direct line 80 and replacing line 110 the computer 71 is connected to the computer 71 and displays the connection state of the connected line. A storage part 40 stores the subscriber number of the local-station side computer 71 and an opposite-station side computer 71' and a password allowing a communication between the local-station computer 71 and opposite station computer 71'. A control/processing part 50 controls the switching part 20, operation/display part 30, interface conversion part 60, and storage part 40 and compares the subscriber numbers and password stored in the storage part 40 with those of the opposite station.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication line switching device used in a computer system, and more particularly, it uses an inexpensive switched line as an alternative path when a working line fails, and at that time uses computer software and hardware. The present invention relates to a communication line switching device that does not need to be changed and a communication line switching method using the same.

[0002]

2. Description of the Related Art Generally, when communication is performed between computers in a computer system, it is cheaper to use an in-company network as a communication line for the communication than to use other networks.
The corporate network is used with priority. Further, in the case of inter-computer communication in an important computer system, a backup line is provided in consideration of the case where a failure occurs in the corporate network, and it is prepared as an alternative path. In that case, it is general to secure a backup line in an external network such as NTT.

Conventionally, the following two methods have been adopted for backing up the fault of the working line.

One of them is a method in which two direct connection lines having the same attribute are prepared so that one direct connection line is used as a working line and the other direct connection line is secured as a protection line. The communication line switching device used in this method switches between the working line and the protection line by switching the line using a relay or the like when a failure occurs.

Another method is to prepare a direct connection line as a working line and to secure a switching line of an external network as a protection line. The signal transmission method is different between the direct connection line and the switched line. Therefore, in addition to switching the working line and the protection line by using a relay or the like like the above-mentioned communication line switching device, the computer side needs equipment for connection of the switching line, and the computer has a working line. It is necessary to support software for switched lines that is different from the original.

[0006]

In the former method described above, it is necessary to secure an extra direct connection line which is not always used, and such a direct connection line is expensive, and such a line is left idle. That is uneconomical.

The latter method is relatively inexpensive because it does not require an extra direct connection line, but it requires equipment for connecting the computer to the backup line, and requires software for the exchange line. However, there is a drawback that it becomes complicated.

Therefore, an object of the present invention is to use an inexpensive switched line as an alternative path when a working line fails, and to use a communication line switching device that does not require the software and hardware of a computer to be changed at that time. It is to provide a communication line switching method.

[0009]

In order to achieve the above object, a communication line switching device of the present invention is a communication line switching device used in a computer system for communicating between a plurality of computers. As a communication line for performing communication between the computers, a working line that is a direct connection line that directly connects the plurality of computers and a protection line that is a switching line used as an alternative path when the working line fails are selectively In order to switch and use, in a communication line switching device provided between each computer and the working line and the protection line, the communication line used by the computer of its own station is switched to the working line side or the protection line side. A switching unit, and a physical interface of the working line and the protection line connected between the switching unit and the protection line. An interface conversion unit for matching with a physical interface, an operation unit for instructing the switching unit to connect the computer of the own station to the working line or the protection line, and the computer of the own station And a storage unit for storing a subscriber number of a computer of the partner station and a password for enabling communication between the computer of the own station and the computer of the partner station, the switching unit and the operation unit. A control / processing unit that controls the interface conversion unit and the storage unit, and compares the subscriber number and the password stored in the storage unit with those of a partner station.

The switching unit may include means for switching the connection between the working computer of the local station and the spare computer.

According to the present invention, a predetermined connection procedure is used when connecting the communication line switching device on the own station side and the communication line switching device on the partner station side using the protection line. A communication line switching method is obtained, which is characterized in that the protection line is used as the communication line after execution to establish a link.

Further, in the communication line switching method of the present invention, when the communication line switching device on the own station side is instructed to switch the working line to the protection line, the protection line is used by the partner station side. The communication line switching device is instructed to switch in accordance with a predetermined procedure, and the communication line switching device on the partner station side is caused to switch from the working line to the protection line.

[0013]

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

FIG. 1 is a block diagram showing the configuration of a computer system including a communication line switching device according to an embodiment of the present invention.

The computer system shown in the figure communicates between a plurality of computers. The communication line switching device according to the present invention is used in such a computer system.
The communication line switching device is a working line which is a direct connection line for directly connecting a plurality of computers as a communication line for communication between a plurality of computers, and a spare line which is a replacement line used as a substitute path when the working line fails. It is for selectively switching between a line and a line, and is provided between each computer and a working line and a protection line.

In this embodiment, the direct connection line 80 provided by the corporate network 90 is used as the working line, and the switching line 110 of the NTT INS net 120 is used as the protection line.
To use. Explaining in detail, as a protection line, NT
It uses the basic interface provided by T's INS Net 120. As is well known, the basic interface is 2
One B (for information transmission) channel and one D (for signal transmission) channel 2B + D.

First, one communication line switching device 10 will be described. The illustrated communication line switching device 10 includes a switching unit 2
0, the operation / display unit 30, the storage unit 40, the control / processing unit 50 connected to the operation / display unit 30 and connected to the storage unit 40, and the interface conversion unit 60 connected to the control / processing unit 50. It consists of and.

The switching unit 20 and the interface conversion unit 60 are connected by a signal line 161, and the switching unit 20 and the control / control unit 60 are connected.
The signal line 162 is connected to the processing unit 50.
The control / processing unit 50 and the interface conversion unit 60 are connected by a signal line 163. The control / processing unit 50 and the operation / display unit 30 are connected by a signal line 164.

The switching unit 20 has a relay 21 and a relay 22. Depending on the contact of the relay 21, the active computer 7
It is connected to either the active terminal line 141 connected to 1 or the standby terminal line 142 connected to the standby computer 72 used at the time of failure. The contact of the relay 22 is normally connected to the working data line 151 connected to the digital service unit 100 on the direct connection line 80 side, and is connected to the signal line 161 connected to the exchange line 110 side when the direct connection line 80 fails.

The operation / display unit 30 is for instructing switching between the direct connection line 80 which is the working line and the switching line 110 which is the protection line. When some trouble occurs in the direct connection line 80, the operator operates / display section 3
An operation for issuing an instruction to switch to the switching line 110 is performed from 0 according to a predetermined procedure. In addition, direct connection 8
When the 0 fault is removed, the operator operates the switching line 110 according to a predetermined procedure from the operation / display unit 30.
The operation for switching from the direct connection line 80 to the direct connection line 80 is performed. Furthermore, in the operation / display unit 30, when a failure occurs in the active computer 71, the operator can operate the
It is possible to switch to the spare computer 72. The instruction by operating the operator is transmitted to the control / processing unit 50 via the signal line 164. The result of the control and processing performed by the control / processing unit 50 is displayed on the operation / display unit 30 via the signal line 164.

The storage unit 40 stores the subscriber numbers of the local station computer and the remote station computer registered in the computer system of the present invention, and between the local station computer and the remote station computer. Stores the password for enabling communication.

The control / processing unit 50 controls the switching unit 20, the storage unit 40, and the interface conversion unit 60 according to the instruction from the operation / display unit 30. Control / processing unit 50
Adds a predetermined code string consisting of a plurality of bytes, which also serves as a switching command for instructing switching of the communication line to either the direct connection line 80 or the switching line 110, to the subscriber number and password of the computer of the partner station. The signal is transmitted to the interface conversion unit 60 via the signal line 163. Further, the control / processing unit 50 controls so as to temporarily store a call setting instruction signal (described later) from the computer on the partner station side in the storage unit 40. Direct connection 80
When the password received from the computer on the partner station side at the time of the failure is the same as that on the computer on the own station side, the control / processing unit 50 connects the relay 22 to the signal line 161 to the switching unit 20. Thus, the control signal is transmitted via the signal line 162. At the same time, the control / processing unit 50 transmits the connection confirmation response signal to which the predetermined calling information, the password matching the computer of the partner station and the subscriber number of the computer of the partner station are added. The control is performed so that 60 is transmitted to the computer on the partner station side. When the connection confirmation response signal is received, the control / processing unit 50 compares the password of the computer on the local station side with the password of the computer on the partner station side, and if they match, the switching unit 20. Then, a control signal is sent out via the signal line 162 to switch the relay 22 to the signal line 161. In either case, when it is determined that the passwords do not match or there is no password, the line is disconnected according to a predetermined procedure.

The interface conversion unit 60 is connected to the digital service unit 130 on the protection line 110 side via the protection data line 152. The interface conversion unit 60 matches the physical interface between the direct connection line 80 and the switching line 110. More specifically, the interface conversion unit 60 performs interface matching between the signal line 161 and one B channel of the basic interface 2B + D, and the signal line 1 from the control / processing unit 50.
The interface matching between 63 and the D channel of the basic interface 2B + D is performed.

The configuration of the communication line switching device 10 of the own station has been described above.
Also has a similar configuration. Therefore, the communication line switching device 10
Those having the same configuration as those are denoted by the same reference numeral with a subscript of dash ('), and the description thereof will be omitted. A communication system is configured by connecting the communication line switching device 10 of the own station to the communication line switching device 10 ′ of the partner station via the direct connection line 80 and the switching line 110.

Next, a communication system using the communication line switching devices 10 and 10 'according to the present invention will be described with reference to FIG. Here, as described above, the direct connection line 80 used as the working line is provided by the corporate network 90. The communication line switching devices 10 and 10 'are connected to the direct connection line 80 via the digital service units 100 and 100', respectively. In addition, the switching line 110 used as a backup line is NTT
INS64 Net 120 of. The communication line switching devices 10 and 10 'are connected to the switching line 11 via the digital service units 130 and 130', respectively.
Connected to 0. The switching line 110 via the NTT INS64 net 120 is a communication line switching device 10 and 10
It is usually logically separated by ´. In this embodiment, a digital line (NTT IN
Since the S64 net 120) is used, digital service units 130 and 130 are used as data transmission devices.
However, when an analog line is used as the switching line 110, it goes without saying that a modulator / demodulator (modem) is used as the data transmission device instead of the digital service unit.

For convenience of explanation, the transmission start side is the active computer 71 and the spare computer 72, and the receiving side is the active computer 71 'and the spare computer 7.
2 '. Further, the communication line switching device 10 on the transmitting side and the communication line switching device 10 'on the receiving side have the same structure, and their functions are not limited to those for transmitting or receiving, and both of them are for transmitting and receiving. It has both functions.

Further, although FIG. 1 shows an embodiment in the case of communication between two stations, by further adding a transmitting / receiving station and a direct connection line 80, communication between a plurality of three or more stations is possible. It may be a computer system for performing.

The establishment of a link between the communication line switching device 10 and the communication line switching device 10 'within the switching line 110 which is a protection line is performed by CCITT (International Telegraph and Telephone Consultative Committee).
Recommendation I. 430, I.I. 441, and I. It is executed based on the procedure defined in 451. Here, as is well known, CCITT Recommendation I.S. 430, I.I. 441, and I. Reference numerals 451 respectively correspond to layers 1, 2 and 3 of the 7-layer model of OSI (Open System Interconnection). CCITT Recommendation I. Reference numeral 430 denotes the first layer of the ISDN user / network interface, that is, electricity for connecting the terminal equipment (TE) and the network terminating equipment (NT).
It specifies the physical conditions. CCITT Recommendation I.
441 is a second ISDN user / network interface
It defines a procedure for realizing efficient and high-quality transfer of information (call control signals, packet information, etc.) transmitted and received between a user and a network through a layer, that is, a D channel. CCITT Recommendation I. 451 defines information on the D channel carried between the user and the network by the third layer of the ISDN user-network interface, that is, the first and second layers, and the procedure using the information.

When there is no fault in the direct connection line 80, as shown in FIG. 1, the active computer 71 uses the relays 21 and 22 of the switching unit 20 in the communication line switching device 10, the digital service unit 100, the direct connection line 80, Digital service unit 100 ', communication line switching device 10'
It is connected to the active computer 71 'via the relay 21' and the relay 22 'of the switching unit 20'. Therefore, the active computer 71 is connected via the direct connection line 80.
And the active computer 71 '.

Next, the operation when some trouble occurs in the direct connection line 80 will be described. When it is determined that a failure has occurred in the direct connection line 80, the communication line switching device 1
0 or the operator on the communication line switching device 10 ′ side, here the operator on the communication line switching device 10 side, instructs the operation / display unit 30 to switch to the switching line 110 according to a predetermined procedure.

When an instruction is sent from the operation / display unit 30,
The control / processing unit 50 includes a subscriber number b of the communication line switching device 10 ′ stored in advance in the storage unit 40, a password between the communication line switching device 10 and the communication line switching device 10 ′, and a communication line. An interface conversion unit transmits a command signal including a predetermined code string composed of a plurality of bytes that also serves as a switching command for instructing the switching device 10 ′ to switch the relay 22 ′ of the switching unit 20 ′ to the switching line 110 side. 6
0 to instruct calling.

Upon receiving the command signal, the interface conversion unit 60 converts the D channel by a predetermined algorithm and sends a call setting instruction signal to the switching line 110 via the digital service unit 130. The switching line 110 sends a call setting instruction signal to the communication line switching device 10 'having the subscriber number b to the digital service unit 130.
And is transmitted to the interface conversion unit 60 '. The interface conversion unit 60 'extracts the call setting instruction signal from the D channel and notifies the control / processing unit 50' of the incoming call.

The control / processing unit 50 'compares the passwords while temporarily storing the call setting instruction signal in the storage unit 40'. If the passwords match, the control / processing unit 50 'instructs the switching unit 20' to switch the relay 22 'to the signal line 161' side. At the same time, the control / processing unit 50 'sends a connection confirmation response signal to which the predetermined ringing information, the same password as that of the communication line switching device 10 and the subscriber number b are added.
Transmit to 0 '. The interface conversion unit 60 ′ that has received the connection confirmation response signal transmits it to the control / processing unit 50 via the digital service unit 130 ′, the switching line 110, the digital service unit 130, and the interface conversion unit 60.

The control / processing unit 50 extracts the connection confirmation response signal from the D channel and compares the passwords. If the passwords match, the control / processing unit 50 instructs the switching unit 20 to connect the relay 22 to the signal line 161 side. The switching unit 20 receives an instruction from the control / processing unit 50.
Completes switching of the relay 22, the link between the communication line switching device 10 and the communication line switching device 10 'is established, and the active computer 71 and the active computer 7 are connected.
The connection with 1'is completed. In this way
Interface conversion unit 60 and interface conversion unit 60
'Is physically matched and the active computer 71
The data between the active computer 71 'and the active computer 71' is transmitted to the B channel of the switching line 110.

In this way, even when the active computer 71 and the active computer 71 'are connected by the switched line 110, they can be used similarly to the direct connection line 80.

Further, in the above, when the passwords do not match or the password is not sent, a predetermined call disconnection procedure is carried out to prevent switching by unauthorized access. .

Switching from the switching line 110 to the direct connection line 80 is performed by the communication line switching device 10 or the communication line switching device 10.
'Any operation / display unit 30 or operation / display unit 3
It is activated by the operator's switching command operation for 0 '. By this switching command instruction, the CCI is transmitted between the control / processing unit 50 and the control / processing unit 50 'via the D channel.
TT Recommendation I. The normal call disconnection procedure defined by 451 is executed to disconnect the call of the switched line 110. At the same time, the control / processing unit 50 and the control / processing unit 50 'respectively include relays 22 and 22 in the switching unit 20 and the switching unit 20', respectively.
The active computer 71 and the active computer 71 ′ are connected to the normal direct connection line 80 by issuing an instruction to switch ′ to the direct connection line 80 side.

Switching between the active and standby computers is carried out as follows. The operator of the communication line switching device 10 performs a switching operation on the operation / display unit 30. In response to this switching operation, the control / processing unit 50 gives a switching instruction to the switching unit 20. In response to this switching instruction, the switching unit 20 switches the relay 21 to realize switching between the active computer 71 and the spare computer 72. Similarly, on the communication line switching device 10 'side, switching between the active computer 71 and the spare computer 72 is performed.

[0039]

As described above, according to the present invention, when the direct connection line is switched to the switching line, the switching line is provided as the direct connection line after executing the line connection procedure between the communication line switching devices and establishing the link. Therefore, there is an effect that an inexpensive switched line can be supplied as an alternative path without changing the software and hardware of the computer.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a computer system including a communication line switching device according to an embodiment of the present invention.

[Explanation of symbols]

10 communication line switching device 20 switching unit 21, 21 ', 22, 22' relay 30 operation / display unit 40 storage unit 50 control / processing unit 60 interface conversion unit 71, 71 'active computer 72, 72' spare computer 80 direct connection line 90 In-house network 100, 100 'Digital service unit 110 Switched line 120 NTT INS64 net 130, 130' Digital service unit 141, 141 'Working terminal line 142, 142' Spare terminal line 151, 151 'Working data line 152, 152 'Spare data lines 161, 161' Signal lines 162, 162 'Signal lines 163, 163' Signal lines 164, 164 'Signal lines

Claims (4)

[Claims] 1. A communication line switching device used in a computer system for communicating between a plurality of computers, wherein the plurality of computers are directly connected to each other as a communication line for communicating between the plurality of computers. Between each computer and the working line and the protection line, in order to selectively use the working line which is the direct connection line and the protection line which is the switching line to be used as an alternative path when the working line fails, In the communication line switching device provided, a switching unit for switching the communication line used by the computer of the own station to the working line side or the protection line side, and the working line connected between the switching unit and the protection line, An interface conversion unit that matches the physical interface of the backup line with the physical interface of the protection line; An operating unit for instructing a unit to connect the computer of the own station to the working line or the protection line; subscriber numbers of the computer of the own station and the computer of the other station; A storage unit that stores a password for enabling communication between a computer and a computer of the partner station; and a storage unit that controls the switching unit, the operation unit, the interface conversion unit, and the storage unit. And a control / processing unit for comparing the subscriber number and the password stored in a unit with those of a partner station. 2. The communication line switching device according to claim 1 on the own station side and the communication line switching device according to claim 1 on the partner station side,
A method for switching a communication line, wherein, when connecting using the protection line, a predetermined connection procedure is executed to establish a link, and then the protection line is used as the communication line. 3. When the communication line switching device according to claim 1 of the own station side is instructed to switch the working line to the protection line, the protection line is used and the partner station side of claim 1 is used. The communication line switching device is instructed to switch in accordance with a predetermined procedure, and the communication line switching device according to claim 1 on the side of the partner station is made to switch from the working line to the protection line. The communication line switching method according to claim 2. 4. A communication line switching device used in a computer system for communicating between a plurality of computers, wherein the plurality of computers are directly connected to each other as a communication line for communicating between the plurality of computers. Between each computer and the working line and the protection line, in order to selectively use the working line which is the direct connection line and the protection line which is the switching line to be used as an alternative path when the working line fails, In the communication line switching device provided, the connection between the working computer of the local station and the spare computer is switched, and the working computer of the local station or the spare computer of the local station is switched to the working line side or the spare line side. A switching unit, and a physical interface of the working line connected between the switching unit and the protection line. Interface and a physical interface of the protection line, and an interface conversion unit for instructing the switching unit which one of the working line and the protection line the computer of the station is connected to, and An operation unit for instructing switching between the active computer of the own station and the spare computer of the own station, subscriber numbers of the computer of the own station and the computer of the partner station, the computer of the own station and the computer of the partner station A storage unit that stores a password that enables communication between users, a control unit that controls the switching unit, the operation unit, the interface conversion unit, and the storage unit, and stores the subscriber number and the storage unit stored in the storage unit. A communication line switching device comprising: a control / processing unit that compares a password with those of a partner station.