JPH02140038A - Communication control equipment - Google Patents

Abstract

PURPOSE:To select a terminal interface without error by applying the control so that a selected terminal equipment and a communication network are connected when a communication request signal from an indefinite communication network is detected to be addressed to itself. CONSTITUTION:When an inputted communication request command signal is detected in a communication request detection circuit 12, a destination address number generating circuit 13 is started to generate a destination address number. A communication request signal generating circuit 14 is started by a control signal from the circuit 13 to generate a communication request signal and inputted to one input of an OR circuit 16. When the title equipment is used as a called party, an affirmative reply signal generating circuit 18 generates an affirmative reply signal, which is inputted to the other input of the OR circuit 16. In the case of receiving either a signal from the circuit 14 or a signal from the circuit 18, the circuit 16 sends the signal to a transmission buffer 20. An OR circuit 22 sends a signal from a buffer 20 or a switching circuit 46 to a network 50 through a signal line 116.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a communication control device, and particularly to a communication control device for communicating via an undefined communication network.

Traditionally, communication networks that can be applied to local area networks and public line networks include C3MA/CD systems using coaxial cables such as Ethernet, optical fiber star networks using bus systems, and TDMA.
There were optical fiber loop networks based on the system.

Fiber optic cables are more resistant to external electromagnetic noise than coaxial cables.

In a bus system like ELherneL, there is no possibility that a node failure will cause the entire system to go down, or the entire system will go down due to node oscillation or cable disconnection.A star network is the central part of the star network. The entire system goes down due to a failure. Furthermore, in a loop network, there is a risk that the entire system will go down due to failure of one node or one link. Duplication of loops complicates the nodes.

In view of the state of the prior art, the applicant has already proposed a grid-like communication network based on the analogy of nerve cells in a living body. For example, see JP-A-58-1:19543. This is a communication network in which communication control elements for multi-car output signals are connected in a multi-connection structure as nodes, and each node transfers digital signals on a first-come, first-served basis.

This grid-like communication network is especially excellent in the following points.

One is that the multi-connection structure provides a high degree of freedom in network topology. Therefore, fault tolerance (survivability) is high, that is, even if a part of the network fails, communication can be adaptively secured through other routes. Next, the best communication path is selected by first-come, first-served logic.

In such a grid communication network where one communication is allowed to occupy part or all of the network continuously over time, a communication control device is required to control the connection between the communication network and the terminal interface. The communication control device on the calling side sends a communication request signal, and the communication control device on the called side receives the communication request signal from the calling side, detects that it is addressed to its own station, and responds. Send a signal. Thereafter, the communication control devices on the calling side and the called side respectively connect the communication network and the terminal interface.

Conventionally, it has been necessary to install a communication control device for each terminal interface between the terminal interface and the communication network. Therefore, if you use multiple terminal interfaces.

Since it is necessary to install multiple communication control devices according to the number of terminal interfaces, a large amount of installation space is required, and the required power supply capacity is also large.

To solve this problem, the communication control device is equipped with a means for switching the terminal interface.

It is conceivable that a terminal interface is selected based on a signal input to a communication control device and connected to a communication network. However, even in that case, the terminal interface selection signal is not electrically transmitted and received between the calling and called parties, so each of the calling and called parties selects the terminal interface. At each device, the operator must input a selection signal, and therefore the specific terminal interface to be used between these operators must be predetermined. , connection could not be established if a mismatch or operational error occurred between the two. In addition, since at least one operator is required for each communication control device, for example, when performing long-distance communication, it is necessary to make inquiries by phone to other operators in advance, which causes operational inconvenience. The 0 or more cases were problems with the connection between the terminal and the communication network in the communication control device, but there are the following problems with connection release.

In a general packet-switched network, after communication ends, each communication node performs processing such as sending a path release request packet and receiving an acknowledgment packet in order to release the end-to-end connection of the communication network. . For this process,
There is packet analysis routing, logical path release within a node, etc., which not only causes complex problems such as network synchronization and packet transfer stagnation, but also takes up CPU time for path release processing, making it impossible to respond quickly.

The present applicant filed Japanese Patent Application No. 132-6554 or ``Node device for amorphous communication network'', and further filed Japanese Patent Application No. 83-8928 concerning ``Communication control device'' for connecting multiple terminals to a communication network.
4, No. 82-1811708, etc.

The communication control device connects a plurality of terminals via an interface circuit that converts a terminal interface into an internal interface in the device.The communication control device selectively connects one of the plurality of terminals to a communication network from the interface circuit. , controls the transmission and reception of signals between the terminal and the network. On the other hand, in a network, a communication path is set up by signals sent and received by terminals via a communication control device, and end-to-end communication is performed.At the end of communication, the terminal instructs to release the connection, and the control device recognizes this. In the zero communication network that releases the connection with the terminal, the node device releases the communication path. However, the relationship between the connection release of the communication control device and the communication path release of the communication network is not specifically disclosed, and the connection release method when using standard RS-232G as the terminal interface is not disclosed. It has not been done.

Purpose The present invention solves the drawbacks of the prior art, and when there are a plurality of terminal interfaces connected to an undefined communication network, it is possible to select these terminal interfaces without error, connect them to the communication network, and operate them. The purpose is to provide a communication control device with good performance.

Another object of the present invention is to provide a simple connection release method, especially a connection release method when RS-2:12G is used as a terminal interface.

In order to achieve the above object, the present invention provides a communication control device that controls the transmission and reception of signals between an unstructured communication network and a terminal connected to the unstructured communication network. a switch means for selecting a connection between the terminal interface and the unstructured communication network; a control means for controlling the selection of the switch means;
a signal input means for inputting a signal from an undefined communication network; a signal detection means for detecting that the signal input from the signal input means is a signal addressed to the local station; and a signal included in the signal input from the signal input means. and terminal interface designation detection means for detecting a signal designating one terminal interface among the plurality of terminal interfaces, and the control means is configured to detect, by the signal detection means, a signal input from the signal input means destined for the own station. If it is detected that the terminal interface is a signal, the terminal interface designation detection means controls the selection of the switch means so as to connect the l terminal interface detected from the signal to the unstructured communication network, and connects the terminal interface to one of the plurality of terminal interfaces. It is characterized by the ability to send and receive signals to and from a communications network.

A detailed explanation will be given below based on the first embodiment of the present invention.

FIG. 1 schematically shows an embodiment of a communication control device according to the present invention.

This device 10 has a communication request detection circuit 12. A communication request command signal is inputted to the communication request detection circuit 12 from a data terminal (DTE) via an interface.
The communication request command signal may be input by the operator from an input device such as a keyboard. When the communication request detection circuit 12 detects the input communication request command signal,
A signal requesting generation of a destination address is sent to the destination address number generation circuit 13. In response, the destination address number generation circuit 13 generates an address number of the destination requesting communication.

The destination address number is placed in the destination address section of a signal sent and received over a communication network as shown in FIG. 3, and consists of an attribute number and a unit number, as shown in the same figure. As shown in the figure, the signals transmitted and received over the communication network, that is, the communication request signal and the acknowledgment signal, consist of a destination address section, a source address section, and a signal type display section, and the destination address section and the source address section are , each consisting of an attribute number and a unit number. The attribute number is the number of multiple DTs existing in the communication control device of the calling or called side.
This indicates the number assigned to a specific DTE interface that is desired to be connected to the network among the E interfaces, and the method of assigning attribute numbers is unified throughout the communication network. That is, for example, a specific D-E interface called A is given the same attribute number in any communication control device connected to the communication network.
A DTE interface called B, which is different from A, is assigned an attribute number different from that assigned to A. On the other hand, the unique number is a device-specific number that identifies a specific communication control device.

The destination address number generation circuit 13 generates a destination address number requesting one communication, that is, a control signal that includes a unit number and an attribute number and operates the one communication request signal generation circuit 14.
It is sent to the communication request signal generation circuit 14 through the signal line 104.

The communication request signal generation circuit 14 is activated by the control signal from the destination address number generation circuit 13, generates one communication request signal, and outputs it to one input of the OR circuit 16 through the signal line 108. When this device becomes the called side, as will be described later, an acknowledgment signal is generated from the acknowledgment signal generation circuit 18 and input to the other input of the OR circuit 16 through the signal line 110.

Therefore, when the communication request signal generation circuit 14 does not generate a communication request signal, the OR circuit 16 generates a logic "0" signal so that the acknowledgment signal output from the acknowledgment signal generation circuit 18 to the OR circuit 16 is not masked. Output to.

When either the communication request signal from the communication request signal generation circuit 14 or the positive response signal from the acknowledgment signal generation circuit 18 is input, the OR circuit 16 transmits this signal to the signal line 1.
12 to the transmission buffer 20. The transmission buffer 20 transmits the signal sent from the OR circuit 16 to the signal line 11.
4 to the OR circuit 22. The OR circuit 22 is
Transmission buffer 20 or switching circuit 46 described later
The signal from the network is sent to the network 50 through the signal line 116.

The reception buffer 40 is connected to the signal line 13 from the network 50.
8 and sends it to the unit identification circuit 64 through a signal line 160.

The signal sent from the network 50 to the reception buffer 40 is a communication request signal or an acknowledgment signal.
As shown in the figure, it consists of a destination address section, a source address section, and a signal type display section. The destination address field contains the control device g! of the other party (called side) to communicate with. The 0 source address part contains the unit number that is the code of the io address and the attribute number assigned to the specific DTE interface of the called side to which you want to connect. It contains the unit number, which is the code for the address of the control unit IO, and the attribute number assigned to the particular DTE interface of the calling party to which it is desired to connect. The signal type display section each includes a code for either a communication request signal or an acknowledgment signal.

The output from the unit number storage circuit 66 is also input to the unit identification circuit 64 through a signal line 162. The unit number storage circuit 66 stores in advance a unit number which is an address code sufficient to identify a specific one of the control devices IO.

The unit identification circuit 64 converts the destination address part of the signal input from the reception buffer 40 into the unit number storage circuit 64.
The communication request signal or acknowledgment signal input from the receiving buffer 40 is compared with the unit number, which is the own address code input from 6, to identify whether or not the communication request signal or acknowledgment signal input from the reception buffer 40 is a signal addressed to the own station. The unit identification circuit 64 is connected to the reception buffer 40.
If the signal is input from the receiver or the signal is addressed to the own station, the communication request signal or acknowledgment signal input from the receiving buffer 4 is output to the attribute identification circuit 60 through the signal line 164, and the signal addressed to the own station is output. If it is not a signal, the receive buffer 40 outputs a reset signal through the signal line 166.

The output from the attribute number storage circuit 62 is also input to the attribute identification circuit 60 through a signal line 168. The attribute number storage circuit 62 stores a plurality of DTEs included in the own device.
Attribute numbers, which are identification numbers that identify each interface, are also stored.

The attribute identification circuit 60 determines whether the attribute number of the communication request signal or acknowledgment signal input from the unit identification circuit 64 is one of the attribute numbers stored in the attribute number storage circuit 62, that is, whether it is the own device. Multiple D
Make sure it is one of the TE interfaces,
The attribute number included in the communication request signal or acknowledgment signal is sent to the DTE interface selection circuit 24. The attribute identification circuit 60 also outputs the communication request signal or acknowledgment signal input from the unit identification circuit 64 to the signal type identification circuit 32 through the signal line 170.

The signal type identification circuit 2 also receives the output from the communication request code storage circuit 34 through the signal line 128.
Communication request codes unified at 0 are stored in advance.

The signal type identification circuit 32 includes a signal type display section of the signal sent from the attribute identification circuit 60 and a communication request code storage circuit 34.
It is determined whether the signal sent from the attribute identification circuit 60 is a communication request signal or not. The signal type identification circuit 32 detects the signal sent from the attribute identification circuit 60 when the signal type display section of the signal sent from the attribute identification circuit 60 is the same as the data of the communication request code output from the communication request code storage circuit 34. The received signal is determined to be a communication request signal, and in this case, a signal indicating that there is a communication request signal is outputted to the acknowledgment signal generation circuit 18 and the OR circuit 26 through the signal line 120.

When the acknowledgment signal generation circuit 18 receives a signal indicating that there is a communication request signal from the signal type identification circuit 32, it is activated, generates an acknowledgment (Ack) signal, and outputs an OR signal through the signal line 110. When the device 10 is the calling side, a communication request signal is generated from the communication request signal generation circuit 14 and sent to the other side of the OR circuit 16 through the signal line 108, as described above. entered into the input. Therefore, the acknowledgment signal generation circuit 18:
When no acknowledgment signal is generated, the OR circuit 16 is a logic "O" signal so that the communication request signal output from the communication request signal generating circuit 14 to the OR circuit 16 is not masked.
Output to.

When the signal type identification circuit 32 determines that the signal sent from the attribute identification circuit 60 is not a communication request signal, the signal type identification circuit 32 sends the signal sent from the attribute identification circuit 60 to the signal type identification circuit 28 through the signal line 126. do.

The output from the acknowledgment code storage circuit 30 is also input to the signal type identification circuit 28 through a credit card 124 . The acknowledgment code storage circuit 30 preliminarily stores an acknowledgment code that is unified for all communication control devices.

The signal type identification circuit 28 compares the signal type display part of the signal sent from the signal type identification circuit 32 with the data of the acknowledgment code output from the acknowledgment code storage circuit 30,
It is determined whether the signal sent from the signal type identification circuit 32 is an acknowledgment signal or not. The signal type identification circuit 28 detects the signal type identification circuit 32 when the signal type display part of the signal sent from the signal type identification circuit 32 is the same as the data of the acknowledgment code output from the acknowledgment code storage circuit 30.
It determines that the signal sent from is an acknowledgment signal, and in this case outputs a signal indicating that there was an acknowledgment signal to the OR circuit 26 through the signal line 122.

When either a signal indicating that there is a communication request signal from the signal type identification circuit 32 or a signal indicating that there is an acknowledgment signal from the signal type identification circuit 28 is input to the OR circuit 26, , outputs an activation signal to the DTE interface selection circuit 24 through the signal line 118.

The DTE interface selection circuit 24 includes an OR circuit 26
The control signal for switching the switching circuit 46 is activated by the activation signal from the switching circuit 46 through the signal line 142 based on the signal for selecting the DTE interface input from the attribute identification circuit 60.
Output to. The switching circuit 46 switches the switch according to the control signal from the DTE interface selection circuit 24 and selects the DTE interface 42 or the DTE interface.
Connect either one of the interfaces 44 to the network 5
Connect to 0 and release the other.

A signal input to the switching circuit 46 from the DTE interface 42 or the DTE interface 44 selected by the switching circuit 46 is transmitted through the signal line 14.
0, is sent to network 50 through OR circuit 22 and signal line 116. Further, the signal input from the network 50 to the switching circuit 46 through the signal line 138 is transmitted to the DT selected by the switching circuit 46.
E interface 42 or DTE interface 44.

The DTE interface 42 has a switching circuit 46
When selected by , it is connected to switching circuit 46 by signal lines 144 and 146 .

DTE interface 42 is also connected to data terminals by signal lines 152 and 154.

DTE interface 44 is similarly connected to switching circuit 46 by signal lines 148 and 150 when selected by switching circuit 46 .

DTE interface 44 is also connected to data terminals by signal lines 156 and 158.

Examples of DTE interfaces 42 and 44 include n5212c serial interface, RS422
Serial interface, Centronics parallel interface, etc. can be used, and 2 or 3 of these can be used.
Just select the type and use it. Note that in this example, 2
Although two DTE interfaces 42 and 44 are provided, the number of DTE interfaces connected to the switching circuit 46 is not limited to two, and may be any number greater than or equal to three.

A system in which the control device 10 shown in FIG. 1 is applied to network communication is shown in FIG. As shown in FIG. 2, a control device 11 similar to the control device 10 shown in FIG.
(la is a data terminal (1) TE) 56 and is also connected to the network 50.

The network 50 configures a communication network by connecting communication control elements of Takuker output signals as nodes in a multi-connection structure,
Each node is a grid network that transfers digital signals on a first-come, first-served basis.

The network 50 also includes a control device lO shown in FIG.
A control device iob similar to the above is connected, and a data terminal ([1TE) 58 is connected to the control device 10b.

The operation of the control device 10 shown in FIG. 1 will be explained with reference to FIG. 2.

The operation example to be described is for a case where communication is performed from data terminal 56 in FIG. 2 to data terminal 58 via network 50.

First, from the data terminal 56 on the calling side in FIG.
A communication request command signal is input to 0a. This communication request command signal is input to the communication request detection circuit 2 shown in FIG. 1 in the control device 10a on the calling side.

When a communication request command signal is input to the communication request detection circuit 12, the communication request detection circuit 12 sends it to the destination address number generation circuit 13. Destination address number generation circuit I
Step 3 creates attribute numbers and unit numbers as shown in FIG. In other words, ・Specific 2 from the entire network
In the process of extracting an end-to-end communication path between points, a signal for selecting which of the DTE interfaces 42 or 44 to connect to the network 50 as the calling side device, that is, a signal assigned to the DTE interface to be connected is transmitted. The own address, that is, the unit number is constructed from the attribute number and the unit number unique to the device. Further, as a destination address, a destination address consisting of a unit number specifying the device on the called side and an attribute number given to the source address, that is, the same attribute number as its own attribute number is generated. These addresses are used together with the communication request command signal sent from the communication request detection circuit 12, as well as the signal! ! It is output to the communication request signal generation circuit 14 through 1104.

The communication request signal generation circuit 14 is activated by the signal from the destination address number generation circuit 13, and the communication request signal from the communication request signal generation circuit 14 is inputted to one input of the OR circuit 16 through the signal line 108. At this time, the control u4 unit f
Since ilOa is the calling side, the acknowledgment signal generation circuit 1
8 does not generate an acknowledgment signal, and the signal from the acknowledgment signal generation circuit 18 has a logic rOJ.
5 is input to the other input. Therefore, the communication request signal from the communication request signal generation circuit 14 is output from the output of the OR circuit 16, and sent to the transmission buffer 20 through the signal line 112.

The communication request signal is input from the transmission buffer 20 to one input of the OR circuit 22 through the signal 1i114. At this time, the other input of the OR circuit 22 is connected to the switching circuit 4.
6 is not sending out a signal, the OR circuit 22 outputs a communication request signal and sends it to the network 50 through the signal line 116.

In the control device 10b on the called side in FIG.

A communication request signal from the control device 10a on the calling side is input from the network 50 to the reception buffer 40 through the signal line 138. In the control device tab on the called side, the input communication request signal is sent from the reception buffer 40 to the unit identification circuit 64 through the signal line 160. In the unit identification circuit 64, the destination address of one communication request signal is
The unit number in the response section is compared with the unit number read from the unit number storage circuit 66 and which is the address code of the control device 10b. The unit identification circuit 64 identifies that the communication request signal is addressed to itself, that is, to the control device 10b, based only on the information in the unit number field.

In this case, since the communication request signal is addressed to the control device 10b, the unit number in the destination address field matches the unit number that is the address code of the own station read from the unit number storage circuit 66.

As a result, the unique identification circuit 64 outputs the communication request signal input from the network 50 to the attribute identification circuit 60 through the signal line 164. Next, in the attribute identification circuit 60, it is confirmed that the attribute number in the destination address part of the communication request signal is the attribute number stored in the attribute number storage circuit 62, and the signal of the attribute number included in this communication request signal is It is output to the interface selection circuit 24.

The communication request signal output from the attribute identification circuit 60 is output to the signal type identification circuit 32. In the signal type identification circuit 32, the signal type display portion of the communication request signal is compared with the communication request code read from the communication request code storage circuit 34. In this case, since a communication request signal is input, the communication request code matches the communication request code read from the communication request code storage circuit 34.

Therefore, an activation signal is output from the signal type identification circuit 32 to the acknowledgment signal generation circuit 8 through the signal line 120.

As a result, an acknowledgment signal is outputted from the acknowledgment signal generating circuit 18 to the OR circuit 16 through the signal line 110. At this time, since the communication request detection circuit 12 of the control device 10b on the called side has not detected the communication request command signal, the signal input from the communication request signal generation circuit 14 to the OR circuit 16 is at the "0" level. has been done. Therefore, the acknowledgment signal output from the acknowledgment signal generation circuit 18 is output from the OR circuit 16 and sent to the network 50 through the transmission buffer 20 and the OR circuit 22.

The signal type identification circuit 32 also outputs an activation signal to the OR circuit 26 through the signal line 120.

Further, from the signal type identification circuit 32 to the signal type identification circuit 28
A communication request signal is output. The communication request signal input to the signal type identification circuit 28 is compared in the signal type identification circuit 28 with the acknowledgment code read from the acknowledgment code storage circuit 3o. In this case, the communication request signal input from the signal type identification circuit 32 does not match the acknowledgment code. Therefore, no signal is output from the signal type identification circuit 28 to the OR circuit 26, and the signal type identification circuit 28
A heliset signal is output from the receiving buffer 40. This resets the reception buffer 40.

As described above, the activation signal from the signal type identification circuit 32 is outputted to the output of the OR circuit 26, and is sent to the DTE interface selection circuit 24 through the signal line 118.

The DTE interface selection circuit 24 is activated by this activation signal and selects a DTE interface that has been selected in advance by a signal from the attribute identification circuit 60, that is, a DTE interface that has been selected by the attribute number of the destination address part of the communication request signal. The switching circuit 4 sends an instruction signal to connect the switching circuit 4 to the network 50.
Send on 6.

This causes switching circuit 46 to connect the selected one of DTE interfaces 42 or 44 to network 50.
is selected, by connecting the signal line 144 to the signal line 140 and the signal line 146 to the signal line 138,
DTP interface 42 is connected to network 50.

In the called side control device tab, D
TE interface 42 or 44 is selected and connected to network 50. DTE interfaces other than the connected DTE interface are released.

The acknowledgment signal output from the transmission buffer 20 of the control bag R10b on the called side to the network 50 is input to the reception buffer 40 of the control device 10a on the calling side.

In the calling side control v4 device 10a, the input 11
The fixed response signal is sent from the reception buffer 40 to the unit identification circuit 64 through the signal line 160. In the unit identification circuit 64, the unit number in the destination address portion of the acknowledgment signal is compared with the unit number read out from the unit number storage circuit 66 and which is the address code of the control device 10a on the calling side. In this case, since the acknowledgment signal is addressed to the control device 10a, the unit number in the destination address field matches the unit number read from the unit number storage circuit 66.

As a result, the unit identification circuit 64 outputs the acknowledgment signal input from the network 50 to the attribute identification circuit 60 through the signal line 164. Attribute identification circuit 6
0, it is confirmed that the attribute number in the destination address part of the acknowledgment signal matches one of the attribute numbers read from the attribute number storage circuit 62, and the signal with this attribute number is connected to the signal line 172. The signal is output to the DTE interface selection circuit 24 through the DTE interface selection circuit 24.

The acknowledgment signal from the attribute identification circuit 60 is output to the signal type identification circuit 32. In the signal type identification circuit 32,
The signal type display section of the acknowledgment signal is compared with the communication request code read from the communication request code storage circuit 34. In this case, since an acknowledgment signal has been input, it does not match the communication request code read out from the communication request code storage circuit 34. Therefore, the acknowledgment signal generation circuit No activation signal is output to 18 and OR circuit 26.

Further, from the signal type identification circuit 32 to the signal type identification circuit 28
An acknowledgment signal is output. Signal type identification circuit 28
The input acknowledgment signal is compared in the signal type identification circuit 28 with the acknowledgment code read out from the acknowledgment code storage circuit 30. In this case, the acknowledgment signal input from the signal type identification circuit 32 matches the acknowledgment code. Therefore, an activation signal is output from the signal type identification circuit 28 to the OR circuit 26 through the signal line 122.

The activation signal from the signal type identification circuit 28 is outputted to the output of the OR circuit 26, and is sent to the DTE interface selection circuit 24 through the signal line 118. The DTE interface selection circuit 24 is activated by this activation signal and connects the DTE interface selected in advance by the signal from the attribute identification circuit 60, that is, the DTE interface 42 or 44 selected in the calling side control device 10a, to the network 50. An instruction signal for doing so is sent to the switching circuit 46.

By completing the above-described operations, the calling data terminal 56 in FIG.
each connected to the network 50 via 0b,
Network communication becomes possible.

In addition, in the third control device 1O other than the calling side and the called side, a communication request signal or a response signal is received from the control device on the calling side or the called side from the network 50 through the receiving buffer 40 in FIG. The signal is input to the unit identification circuit 64. The unit identification circuit 64 compares these input signals with the unit number, which is the address code of its own station, sent from the unit number storage circuit 66, and determines that the signals are not addressed to its own station. The unit identification circuit 64 thereby sends a reset signal to the reception buffer 40 through the signal &1166, and discards the input signal not addressed to its own station. The unit identification circuit 66 does not output the signal input from the network 50 to the attribute identification circuit 60.

By performing such processing, the third control U4 device 10 other than the calling side and the called side discards communication request signals or response signals that are not addressed to the own station.

According to this embodiment, the attribute number included in the communication request signal on the called side and the acknowledgment signal on the calling side is identified by the attribute identification circuit 60, and the identified attribute number is sent to the TE interface selection circuit 24. The DTE interface 42 or 44 is selected in advance in the DTE interface selection circuit 24. The signal type identification circuit 3 detects the communication request signal or acknowledgment signal addressed to the own station.
2 or 28 activates the DTE interface selection circuit 24, which switches the switching circuit 46 to connect the selected DTE interface 42 or 44 to the network 50.

Therefore, since the DTE interface 42 or 44 can be selected and connected to the network 50 according to the attribute number included in the communication request signal or the acknowledgment signal, it is possible to connect the DTE interface 42 or 44 to the network 50 separately. There is no need to install a communication control device to control it. In this way, multiple DTE interfaces can be controlled by one communication control device, which saves space and reduces power supply capacity. Can be done. Furthermore, there is no need to design a communication control device for each different DTE interface.

According to this embodiment, a specific D is specified by specifying an address value.
Since the bus is fixed for the TE interface, among the multiple DTE-DCE interfaces of multiple communication control devices connected to the amorphous communication network,
End-to-end connection between a specific device and a specific DTE-DCEC fin interface can be performed without mutual error. Furthermore, even when a plurality of different DTE-DCE interfaces are installed in the communication control device, it is possible to connect the same type of interfaces of the DTE-DCE interfaces at both ends to each other without error. Moreover, the specific DT to be connected
Only one calling side needs to specify the E interface, and the operator on the called side does not need to specify the DTE interface. No need and easy to operate.

By using the control device 10 of this embodiment, the input/output port of the shell personal computer can be directly used as a DTE interface to connect to a network.

Furthermore, it is possible to select either a data terminal that performs high-speed long-distance communication or a data terminal that performs low-speed short-distance communication to connect to the network.

Furthermore, a host computer that performs high-speed long-distance communication,
It is also possible to connect via a network to a data terminal that receives input from a printer or scanner.

As described above, according to the control device of this embodiment, a plurality of DTs
Since the DTE interface selected from the E interfaces can be connected to the network, the scope of application of the network is expanded.

Next, a connection release method of the communication control device according to the m2 embodiment of the present invention will be explained using FIGS. 4 to 7. Figure 6 shows a multimedia network.

Personal computer a, workstation b, f
, host computer C, modem d4 dumb terminal e
etc. are connected to the communication network 70 via the communication control device IO. The communication network 70 is constituted by a node device, for example, a node device of the amorphous communication network of Japanese Patent Application No. 62-6554 or the present applicant. FIG. 7 shows an example of this, in which node devices 10 are connected to terminals 14 or other node devices in a grid pattern through transmission paths 12 to form a communication network. Terminals a to f in FIG. 5 are connected to a node device of a communication network 70. Communication is performed from the communication control device 10 through the node device.

When the terminals a to f make a call, the communication control device 10 sends an outbound communication request signal to the node device.

The node device detects the arrival of the outgoing signal using first-come, first-served logic, detects the transmission line where the outgoing signal arrived first, transfers this outgoing signal to all other empty transmission lines, and then transfers the outgoing signal to all the nodes. A communication control device 10 that broadcasts to the device and connects to each node device.
will be received. The communication control device that has received the communication request signal indicating that the second terminal has completed returns an acknowledgment signal. The node device detects the incoming signal using first-come, first-served logic in the same way as the outgoing signal, broadcasts it to an empty transmission path, and receives it by the communication control device 10 on the calling side. The node device connects the transmission paths of the outgoing signal and inbound signal that arrive first, and when the end-to-end communication path relayed by the node device is fixed, the node device transmits the communication signal. When the signal maintains a predetermined logical state for a predetermined monitoring time or longer, it is determined that communication has ended, and the connection between the transmission lines is released.

Next, a connection release method of the communication control device 10 will be explained. FIG. 4 shows a connection release circuit of the control device 10.

The communication control device connects a plurality of terminals through corresponding interface circuits (IF circuits).When a switching circuit 1 receives a control signal 1a from a control section, it connects a plurality of terminals through corresponding interface circuits (IF circuits).
The IF circuit is selectively connected to the coater 5 and decoder 4 from among the F circuits, and the connection is released when the NOROR circuit power signal 8a, "O", is input.

The IF circuit is connected to the terminal through the interface R5232C, and is connected to the switching circuit 1 through the coater 5 and decoder 4.
The IF circuit connects with the terminal via a TTL interface and performs conversion between the two interfaces. When the terminal is inactive, the IF circuit receives the communication request signal RTS "0", the transmission signal RXD,
Input "O" and send the carrier detection signal CD to the terminal.
“O”, outputs the received signal RXD°゛0°゛, and sends the above-mentioned RS232CO') signal to the switching circuit 1.
Convert to L level and input/output. The switching circuit 1 is in a rest state and sends a TTL signal RT to the coater 5.
The decoder 4 outputs a signal RXD at the TL level.

Each "o" of the CD is input. When the coater 5 is at rest, it outputs °0'' of the transmission line 5a, and when it is connected to the terminal via the IF circuit by switching the switching circuit 1, the coater 5 outputs a transmission request signal RTS from the terminal. "1'", input the transmission signal RXD, set the Manchester code of the transmission line to "1", and intermittent the transmission signal "1".
","0°' are output to the node device from the transmission line 5a.

When the decoder 4 receives the Manchester code from the node device through the transmission line 4a of the transmission path, it inverts the carrier detection signal CD to "L", outputs the reception signal RXD, and passes it from the switching circuit 1 to the IF to the terminal. will be received. The decoder 4 has a monitoring time length similar to that of the node device described above, and if the Manchester code on the reception line 4a continues to be "0" for more than the monitoring time length, the carrier detection signal C
Set D to "0pa" and set the received signal RXII to "0pa."

A connection release request from a terminal, that is, a connection request signal, R
ST, "O", ready signal D including power on of terminal
SR, "0", when a release signal is input by a terminal connection release operation, a control circuit (not shown) issues a connection release request signal 3.
a is outputted to the bus release circuit 3, which outputs an output signal ゛1''. The NOR circuit 8 receives the output signal 3b from the space release request circuit 3.

When "i" or the carrier detection signal CD, "O°', from the decoder 4 is input as 1" through the inverter 7, "0" is output to the switching circuit 1.

Release switching.

Next, in FIG. 6, it is assumed that the connection is released after data communication between terminals and f is completed. Suppose you want to release the connection from the terminal side. In FIG. 4, when a connection release is detected by the connection release request detection circuit 3 (this may be composed of a simple switch) and its output 3b changes from "0" to °゛l, the NOR circuit 8 output signal 8b,
“0′” is input to the switching circuit 1. When the switching circuit 1 detects this signal "o", it disconnects the IF circuit 2 side and the communication network side, which have been connected so far, and reduces the signal RTS of the coater 5 from 1'' to 0''. The coater 5 that receives the signal RTS outputs the output to the communication network.
”, and this is transmitted to the decoder 4 of the communication control device of the other terminal f.Next, the decoder 4 in the communication control device of the terminal f detects that the received signal from the communication network has exceeded a certain period of time.
′, the signal CD changes from “1′° to
Drop to “O”. This signal "o" is inverted by the impark 7, and °l° is input to the NOR circuit 8, and its output becomes °'0. Therefore, the switching circuit l is connected to the same IF as in the communication control device 1. Cut the connection between the circuit and the communication network, drop the signal RTS to the coater 5 to °O'',
The output of the coater 5 to the communication network becomes "0'°. At this stage, the signals CD and RTS of the terminal f both become O"°, and the carrier of the communication path 5 connecting the terminal f disappears to 0. When the transmission path signal ``0°°'' continues and the monitoring time elapses, the communication network node device autonomously releases the communication path connecting terminals and f, and responds to new communication requests by opening the communication path. 0 or more explanations that can be provided are when a release request is made from the terminal f.If a release request is made from the terminal f, the connection is released by the same operation.

In addition, by setting the signal RTS to "O" through program control, keyboard input, etc. from the terminal side, the connection release request detection circuit 3 sets the output 3b to "0",
Since the connection is released using a similar algorithm, it also has the effect of allowing paths to be released by remote operation or program control.

In this embodiment, R5-232G is used for the terminal interface, but R5-422 may of course be used.

The path release request detection circuit 3 detects that there is a path release request “l′′,
The switching circuit 1 may be configured with a switch that outputs "O" without a request, and the switching circuit 1 can be configured with a combination of simple digital logic elements P1 to P4 as shown in FIG. 5.This circuit '1 input from NOR circuit 8
This is a switch that turns on and off the connection in response to ” and 0.

Effects According to the present invention, when it is detected that a communication request signal or a response signal from an undefined communication network is addressed to itself, the switch means is operated to connect a terminal selected from a plurality of terminals to the communication network. Since the connection is controlled, one control device can control the connection between a plurality of terminals and a communication network. Moreover, since the terminal is selected by the address of the specified signal included in the communication request signal or response signal, the same type of interfaces can be connected to each other at both ends without error, and the interface can be specified only on the calling side. Since the operator on the called side does not need to specify the DTE interface, the operation is easy.

In addition, the connection release method of the present invention detects a release from the other terminal when the signal on the transmission line continues to be in a predetermined logical state for a predetermined period or more, similar to the node equipment, and the release request from the terminal is detected by the terminal. Since the connection release request is detected by the release operation and the terminal interface, the connection release request can be detected independently from the logic of other control circuits of the communication control device.The control logic is simple, so the configuration of the connection release circuit is simplified. The number of parts is small and it can be effectively applied to general communication control devices.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of a communication control device according to the present invention. FIG. 2 is a schematic configuration diagram showing a system in which the device of FIG. 1 is applied to network communication. FIG. 4 is a functional block diagram of a connection release circuit showing an example of a connection release method for a communication control device according to the present invention; FIG. FIG. 6 is a relay system diagram showing an example of the configuration of a communication network to which the present invention is applied; FIG. 7 is a diagram showing an example of an amorphous communication network. -・Explanation of part symbols 11. Switching circuit 22. , terminal interface circuit 39. , connection release request circuit 4, . 5. 10. 12. 13. 14. 18. 20. 24. 28.32 30. 34. 40. 42.44 46. 50. 56.58 60. 62. 64. Decoder Kog communication control device Communication request detection circuit Destination address number generation circuit Communication request signal generation circuit Acknowledgment signal generation circuit Transmission buffer DTE interface selection circuit Signal type identification circuit Acknowledgment code storage circuit Communication request code storage circuit Reception buffer DTE interface switching circuit Network Data terminal attribute identification circuit Attribute number storage circuit Unit identification circuit 88°Unit!・Number storage circuit 70°, communication network

Claims (1)

[Scope of Claims] 1. A communication control device that controls transmission and reception of signals between an amorphous communication network and a terminal connected to the amorphous communication network, the device comprising: a plurality of terminals connected to the terminal; a switch means for selecting a connection between an interface and the amorphous communication network; a control means for controlling the selection of the switch means; a signal input means for inputting a signal from the amorphous communication network; and a signal input means for inputting a signal from the amorphous communication network. a signal detection means for detecting that the signal input from the signal input means is a signal addressed to the own station; and a signal detection means included in the signal input from the signal input means, which specifies one terminal interface among the plurality of terminal interfaces. and terminal interface designation detection means for detecting a signal to be sent to the terminal interface, and the control means, when the signal detection means detects that the signal input from the signal input means is a signal addressed to the own station, The selection of the switch means is controlled so that the terminal interface designation detecting means connects the one terminal interface detected from the signal to the amorphous communication network, and connects any one of the plurality of terminal interfaces to the communication network. A communication control device that is capable of transmitting and receiving signals to and from. 2. The device according to claim 1, further comprising:
and communication request signal detection means for detecting that the signal input from the signal input means is a communication request signal when the signal detection means detects that the signal input from the signal input means is a signal addressed to the own station. . A communication control device, wherein the control means controls the selection of the switch means based on an output from the communication request signal detection means. 3. The device according to claim 1 or 2, further comprising: when the signal detection means detects that the signal input from the signal input means is a signal addressed to the own station, A communication control device comprising: an acknowledgment signal detection means for detecting that is an acknowledgment signal; and the control means controls the selection of the switch means based on an output from the acknowledgment signal detection means. Device. 4. A connection release method for a communication control device connected to an amorphous communication network, in which a node device is connected to a communication control device or a node device via a transmission path, and a plurality of terminals are connected, and the connection between the terminal and the node device is a communication control device that controls transmission and reception of signals and connects one terminal to a node device, and the node device sends and receives signals to and from the communication control device or the node device via a transmission path, and connects the transmission paths. , an amorphous communication network that relays signals sent and received between terminals and releases the connection when the signal continues in a predetermined logic state for a predetermined period of time, the communication control device is configured to: When the converted signal is input from the reception line, it is converted into a reception signal and output, and the carrier detection signal is inverted to positive. a signal input means for inverting a carrier detection signal to negative; inputting a transmission signal and a transmission request signal from a terminal, converting the transmission signal into the encoded signal, and transmitting the signal to the node device from the transmission line of the transmission path; a terminal interface that is connected to a terminal and converts the interface of the terminal into an input interface of the signal output means and an output interface of the signal input means; a switch that connects the signal input/output means and the terminal interface; a switch that receives outputs from the control means according to the negation of the carrier detection signal, the negation of the terminal transmission request signal and the ready signal, and the connection release operation of the terminal; and connection release means for releasing the connection of the switch means, when the switch means releases the connection, it outputs a negation of the connection request signal to the signal output means, and the signal output means transmits the signal of the transmission line to the signal output means. A connection release method for a communication control device, characterized in that a predetermined logical state is maintained and the node device releases a connection between transmission lines. 5. The connection release method according to claim 4, wherein when an RTS signal is received from a terminal of interface standard RS-232C and a negation of the signal is detected, the switch means is released. 6. In the connection release method according to claim 5, the RT
A connection release method characterized in that a DTR signal is used instead of an S signal, and when a negation of the signal is detected, the switch means is released. 7. The connection release method according to claim 4, wherein RS-422 is used as an interface of the terminal, and connection termination is detected from the interface.