JPS6243579B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a connection control method for an information transmission/reception system when information processing devices such as computers and terminals communicate using a communication network.

Figure 1 shows the so-called virtual connection control method.
Diagrams explaining call settings; Figure 2 is a diagram showing the case where two virtual calls are configured;
The figure is a diagram illustrating a general method for preventing two virtual calls from being set up. In Figures 1 to 3, PA and PB are information processing devices, CN is a communication network, A ₁ to A _o are addresses of logical channels assigned to information processing device PA, and B ₁ to B _o are information processing devices. Each shows the address of the logical channel assigned to the PB. Also, the information processing device PA has a device address α.
is attached to the information processing device PB, and the device address β is attached to the information processing device PB.
is attached.

In order for the information processing device PA to communicate with the information processing device PB, it is necessary to set up a logical path, that is, a virtual call, between the information processing devices PA and PB. When starting a virtual call setup from the information processing device PA, the information processing device PA sends a virtual call setup command with the information processing device PB to the communication network CN through an unused logical channel, for example, logical channel A ₃ . do. Communication network
CN is an unused logical channel of information processing device PB
Send a virtual call setup request command through _B5 . At this time, the device address α of the information processing device PA is indicated in the virtual call setup request command. The information processing device PB is
If it is ready to start communication with the information processing device PA, it sends an acknowledgment to the communication network CN through the logical channel _B5 that received the virtual call setup command. The communication network CN transmits the acknowledgment to the information processing device PA. This allows the information processing device to
A logical path, ie, a virtual call, is now set up between PA and PB, and the virtual call is composed of logical channels A3 and B5 (see FIG. 1). Setting up a virtual call can also be started from the information processing device PB in the same way. It is also possible to set up between the information processing devices PA and PB using another logical channel.

When information processing devices PA and PB communicate, there are systems in which it is sufficient to have only one virtual call between the information processing devices PA and PB, but it would be a problem if multiple virtual calls were set up. .
In such a system, for example, when information processing device PA attempts to start communication with PB, if a virtual call setup request command is received from information processing device PB, it returns an affirmative response to it, and
Control is performed so that the information processing device PA does not send a virtual call setup command. If a virtual call setup request command is also issued from the information processing device PA, two different logical channel sets, for example A ₃ ,
Two virtual calls are set up through _B5 , _A5 , and _B6 .

However, if the information processing devices PA and PB start setting up a virtual call at the same time, both the information processing devices PA and PB will send a virtual call setup request command to the communication network CN. In this case, from one information processing device's perspective, it means that it has sent a virtual call setup request command and then received a virtual call setup request command from the other party. In order to set up only one virtual call between information processing devices PA and PB, either information processing device returns an affirmative response to the received virtual call setup request command, and the other information processing device The device must respond negatively to the received virtual call setup request command. If a negative response is returned, the communication network CN does not set up a virtual call, and if a positive response is returned, the communication network CN sets up a virtual call.

In the prior art, which virtual call setup request should be given priority for each combination of information processing devices connected to the network is fixedly determined at the time of system setup. For example, information processing equipment
In the combination of PA and PB, it is decided that the virtual call setup request from the information processing device PA will be given priority, and if the virtual call setup request command is passed between the information processing devices PA and PB, the information processing The device PA returns a negative response, thereby validating only the virtual call setup request from the information processing device PA.

The above conventional method has the following problems. That is, each information processing device must have a table for storing which of the partner information processing devices that can be combined should be prioritized. Furthermore, when a new information processing device joins the network, priority relationships must be set in the table for the information processing devices that have already joined. Having to perform such setting work every time is inconvenient and lacks flexibility. Furthermore, the table that stores the priority relationships occupies a corresponding amount of memory, which is not preferable in terms of effective memory utilization.

The present invention is intended to eliminate the above-mentioned drawbacks, and in a system in which information processing devices communicate through a communication network, when the information processing device detects a miscommunication between virtual call setup requests, the received virtual call setup request An object of the present invention is to provide a connection control method for a communication system that allows a user to easily decide whether to return an affirmative response or a negative response to a command. Therefore, in the present invention, when one information processing device specifies and outputs the corresponding other information processing device via the communication network, and receives a signal affirming the connection,
In an information transmission/reception system that communicates with the other information processing device through a communication network, when a virtual call setup request command is sent specifying the other information processing device, the other information processing device simultaneously performs the information processing of the one of the above. When a virtual call setup request command is sent by specifying a device, each of the above-mentioned one information processing device and the above-mentioned other information processing device compares the values of its own address and the address of the other party, and the comparison result is determined as a predetermined value. When the predetermined conditions are met, a positive response is sent back, and when the predetermined conditions are not met, a negative response is sent back. The present invention will be explained in detail below.

If the information processing device receives a virtual call setup request command from the same party after sending the virtual call setup request command, that is, if it detects a mistake in the virtual call setup requests, the information processing device transmits the virtual call setup request. Compare the address of the other device set in the command with the address of your own device. At this time, it is determined whether or not it has priority, that is, whether to return a negative response or an affirmative response to the received virtual call setup request, according to criteria agreed upon in advance with the other party. One example of the criterion is to compare the magnitude of device addresses and give priority to the virtual call setup request issued from the larger one. For example, assume that the device address α of the information processing device PA is “100” and the device address β of the information processing device PB is “090”. If the information processing device PA detects that a misunderstanding has occurred when receiving a virtual call, it compares the device addresses α and β. Since α>β, the information processing device
PA takes priority and returns a negative response to the virtual call setup request command from information processing device PB. On the information processing device PB side, the device addresses α and β are compared using the same logic, and since β<α, the information processing device PA has priority, and the information processing device PA
Returns an acknowledgment to the virtual call setup request command from. A device address is uniquely given to each information processing device connected to the communication network CN, and each information processing device stores its own device address.

Figure 4 is a functional block diagram of the information processing device, Figure 5
The figure is a functional block diagram of an example of a command control section according to the present invention.

In FIGS. 4 and 5, 1 is a data processing unit (application program execution unit), 2
is a command control unit, 3 is a line control unit, 4 is a VC setting request command creation unit, 5 is an acknowledgment creation unit, 6
is a negative response generation unit, 7 is a VC setting request reception unit, 8
Reference numeral denotes a VC setting request command transmission storage section, 9 a response reception section, 10 a destination device address storage section, 11 a magnitude comparison section, and 12 a local device address storage section. Note that all the information processing devices connected to the communication network CN have functions as shown in FIGS. 4 and 5, and VC is an abbreviation for virtual call.

The data processing section 1 is a section that executes an application program, the command control section 2 is a section that controls the exchange of data up to the point where it reaches the other party's information processing device, and the line control section 3 is a section that controls the communication network CN. This is the part that controls data exchange between the port and the information processing device. The present invention mainly relates to a command control section of an information processing device.

Next, the operation shown in FIG. 5 will be explained. Data processing section 1
When a virtual call setup request is issued to the command control unit, the VC setup request command creation unit 4 creates a virtual call setup request command. The created virtual call setup request command is sent to the line control unit 3, and the communication network
Sent to CN. At this time, the command control unit 2 uses the VC setting request transmission storage unit 8 to send the virtual
It remembers that the call setup request command was sent. This storage remains valid until a response to the virtual call setup request command is received.
While the sending of the virtual call setting request command is stored in the VC setting request command transmission storage unit 8, a virtual call setting request command is received from the other party's information processing device that sent the virtual call setting request command. If so,
The destination device address is taken out from the VC setting request receiving section 7 and stored in the destination device address storage section 10. The size comparison unit 11 compares the address of the other party's device and the address of its own device. Size comparison section 11
sends a signal with a predetermined logical value to the negative response generation unit 6 when the local device address is larger, and sends a signal with a predetermined logical value to the positive response generation unit 5 when the address of the other device is larger. . When receiving a signal with a predetermined logical value, the acknowledgment generation unit 5 generates and transmits an acknowledgment. Furthermore, when receiving a signal with a predetermined logical value, the negative response creation section 6 creates and transmits a negative response.

As is clear from the above description, according to the present invention, when a virtual call setup request is misplaced between two information processing devices, the destination device address and the local device address are compared, and the comparison result is Since one virtual call setup request is determined to be valid, the logical path between two information processing devices, that is, the virtual call is always set to one.
It can be made into a book. Furthermore, there is no need to memorize priority relationships with other information processing devices, and even if a new information processing device is connected to the communication network, information processing devices already connected to the network will be affected. Never.

[Brief explanation of the drawing]

Figure 1 is a diagram explaining the setting of a virtual call, Figure 2 is a diagram showing a case where two virtual calls are set, and Figure 3 is a diagram showing how to prevent two virtual calls from being set. FIG. 4 is a functional block diagram of an information processing apparatus, and FIG. 5 is a functional block diagram of an example of a command control section according to the present invention. 1...Data processing unit, 2...Command control unit,
3... Line control unit, 4... VC setting request command creation unit, 5... Acknowledgment creation unit, 6... Negative response creation unit, 7... VC setting request receiving unit, 8... VC setting request command transmission Storage unit, 9...Response receiving unit,
10... Other device address storage section, 11... Size comparison section, 12... Own device address storage section, PA
and PB...information processing device, CN...communication network, _A1 to An...address of the logical channel assigned to the information processing device PA, _B1 to Bn...the address of the logical channel assigned to the information processing device PB address.

Claims (1)

[Claims] 1 Information that allows one information processing device to specify and output the corresponding other information processing device via a communication network, and to communicate with the other information processing device via the communication network at the time of receiving a signal confirming the connection. In the transmitting/receiving system, when the one information processing device and the other information processing device have joined the communication network under conditions that allow the use of multiple logical channels, one information processing device transmits the information of the other. If the other information processing device specifies output to one of the information processing devices at the same time as the processing device is specified for output, at least one of the one information processing device and the other information processing device will have to send its own address and the other party's address. A connection control method for an information sending/receiving system, characterized in that address values are compared, and only when the comparison result satisfies a predetermined condition, the affirmative signal is returned for information communication.