JPH09219752A - Isdn terminal adaptor provided with call-back function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To charge communication tariff to a callee-side server by calling again caller-side client from the terminating server when the caller-side client calls the callee-side server. SOLUTION: A call-back function control circuit 14 is connected to a call control circuit 11. If the contents of the message received from an ISDN circuit 20 via the circuit 11, and an ISDN interface circuit 13 are equal to those of the message to which the call-back request information is given, the circuit 14 takes the caller subscriber number out of the received message to store it in a memory 10. Then the circuit 14 decides whether the subscriber number taken out the received message is identical with the opposite party of communication to which the call-back function registered previously in the memory 10 is permitted and then starts the call-back function. The circuit 14 performs the connection processing with the caller subscriber number stored in the memory 10 used as the terminating address.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the communication of a personal computer connected to a serial port of an ISDN terminal adapter, and when a file is transferred between a client on the calling side and a server on the called side, the call is sent from the client side and the server side is received. The present invention relates to a terminal adapter that can be used on an ISDN line having a function (callback function) that allows the server side to call back to the client side.

[0002]

2. Description of the Related Art A conventional ISDN terminal adapter is
When making a call from a computer connected to the serial port, the calling party paid the communication charge. Therefore, in the client / server system, when the client side sends to the server side to connect, and the client side obtains the information on the server side, even if the server side wants to pass the information free of charge as a service, the communication fee is sent to the calling side. Was charged, and it was impossible for the server side to cover the communication charges.

[0003]

The first problem is that when the client side wants to send information to the server side to connect and the client side wants to obtain the information existing on the server side,
Even if the server side wants to provide information as a service free of charge, the communication fee is charged to the client side of the sender, and it is impossible for the server side to cover the communication fee.

The reason for this is that since the sender is charged for all the communication charges, there is no means for sending from the called server to the calling client. Therefore, the communication charge was always borne by the client.

[0005]

The ISDN terminal adapter of the present invention can realize the callback function even if the server side personal computer does not support the callback function. In addition, a security function is provided to prevent callback from targeting an unspecified large number of users, and the ISDN terminal adapter on the server side can be used to verify the caller number to determine whether or not the party has been registered in advance and has specified connection permission. However, if the caller is a connection-permitted caller, the call is redone from the server side to connect. In the case of a caller who is not permitted to connect, it is possible to construct a system that ignores the other party without performing the redialing operation.

The ISDN terminal adapter of the present invention on the calling side sends outgoing information to which callback request information is added. In the ISDN terminal adapter of the present invention on the receiving side,
An interface circuit is provided for recognizing the calling party's subscriber number, further recognizing the call back request information by using the caller number notification service of the ISDN line, and for calling again to the caller after the communication is disconnected. There is. (14 in FIG. 1) For example, a call is issued from a personal computer connected to the ISDN terminal adapter of the caller on the client side by using a call-out command, and the call-back request information is received by the incoming ISDN terminal adapter on the server side. When it is recognized, after confirming that the communication has been cut off, the communication is established again by transmitting to the caller.

As a result, it becomes possible for the client side to obtain the information on the server side for the communication fee charged on the server side.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an IS according to an embodiment of the present invention.
It is a device block diagram of a DN terminal adapter.

In FIG. 1, an ISDN terminal adapter 1 includes a call control circuit 11 for controlling a communication protocol of an ISDN line, and an ISDN interface control circuit 13 for connecting to an ISDN line to transfer messages and data.
And a serial interface control circuit 12 having a non-communication monitoring function for monitoring signal line control and transmission / reception of data via the serial interface with the personal computer 15 and monitoring a state in which data being transferred is not transmitted / received for a certain period of time
And a function for reading the subscriber's subscriber number from the incoming call setup message, and identifying whether the subscriber number registered in advance matches the subscriber's subscriber number read from the call setup message. A call-back function control circuit 14 having an identification function for controlling the caller, and a memory 10 for holding the subscriber number of the caller and the subscriber number for identifying the caller in order to realize the call-back function. .

The call control circuit 11 is connected to the memory 10, the serial interface circuit 12, the ISDN interface control circuit 13, and the callback control circuit 14, and is connected to the ISD.
ISDN line 2 via N interface control circuit 13
0 communication protocol control is performed.

The serial interface control circuit 12 includes
Control of transmission / reception of messages with the signal line of the interface with the serial interface 21 and monitoring of no data transfer for a certain period of time are monitored, and the state is monitored by the call control circuit 11
It has a non-communication monitoring function for notifying the callback function control circuit 14 via the.

The ISDN interface control circuit 13 is
It controls the interface with the ISDN line 20, synchronizes the line, establishes a link, and controls the sending and receiving of messages.

The callback function control circuit 14 is connected to the call control circuit 11, and the content of the incoming message received from the ISDN line 20 via the call control circuit 11 and the ISDN interface circuit 13 is provided with callback request information. If it is a message, the subscriber number of the sender is extracted from the incoming message and stored in the memory 10. It also has a function of registering in the memory 10 the subscriber number of the communication partner who permits the callback function received from the personal computer 15 via the serial interface control circuit 12.

Further, the callback function control circuit 14 is
It is judged whether or not the subscriber number of the caller extracted from the incoming message is the communication partner registered in the memory 10 in advance, and the callback function is activated.

The memory 10 is connected to the call control circuit 11, and the callback function control circuit 14 stores, via the call control circuit 11, the subscriber number of the caller who requested the callback and the party to whom the callback is permitted. Register the incoming call subscriber number.

FIG. 2 is a block diagram showing an example of use of the ISDN terminal adapter of FIG. In the figure, FIG.
ISDN same as ISDN terminal adapter 1 shown in
Communication using the callback function is realized using the terminal adapters 31 and 32. A client side personal computer (personal computer) 30 and a server side personal computer 33 are connected to an ISDN terminal adapter 31 or 32, and each adapter is connected via an ISDN network.

When data is transferred from the originating client personal computer 30 to the destination server personal computer 33, I
The SDN adapters 31 and 32 perform data communication by using a callback function in order to charge a communication fee to the server side. There are two types of sequences for realizing the callback function in this case, and these will be described with reference to the sequence charts of FIGS. 1, 2, 3, and 4.

First, the operation of sequence 1 for implementing the callback function will be described with reference to the sequence chart of FIG.

When making a call back request from the calling side client personal computer 30, the call back request information is added to the end of the called sub address number of the call information 40 and the call is made. The data transmitted by the personal computer 30 passes through the serial interface connected to the originating ISDN terminal adapter 31 having the configuration of FIG.
It is received by the serial interface control circuit 12 in the N terminal adapter 31. The callback function control circuit 14 collates and analyzes the received outgoing information,
If the call back request information is at the end of the called sub-address in the outgoing information, the call setup message (hereinafter, SET
Callback request information is added to the end of the destination subaddress of the UPDN) and SETUP 41 is transmitted to the ISDN line 20 through the ISDN interface control circuit 13.

In the destination ISDN terminal adapter 32 having the configuration of FIG. 1 connected to the server on the receiving side,
The ISDN interface control circuit 13 controls the ISDN line 2
Receive SETUP 41 from 0. The callback function control circuit 14 passes through the call control circuit 11 and the SETUP 41
Matches and analyzes the destination subaddress in. If there is specified callback request information at the end of the destination subaddress,
Since the calling ISDN terminal adapter 31 requests the callback function, the callback function control circuit 14
Stores in memory 10 the subscriber number of the caller in SETUP 41. Call message 42 on the called side
(Hereinafter referred to as ALERT), the call control circuit 11 is SE
It is transmitted to the ISDN line 22 to notify the caller that the TUP 41 has been normally received.

The originating ISDN terminal adapter 31 is A
When the LERT 42 is received, it is determined that the receiving side has received the callback function, and the disconnection message 43 (hereinafter, DISC)
Is called to the called party to disconnect the outgoing call that requested the callback function.

The destination ISDN terminal adapter 32 is
When the call control circuit 11 recognizes that the outgoing call requesting the callback function has been released by the release completion message 45 (hereinafter referred to as REL COMP), the callback function control circuit 14 is activated. The callback function control circuit 14 transmits the SETUP 46 by using the caller number stored in the memory 10 as the destination address and performs the communication path connection process. In response to this, the originating ISDN terminal adapter 32 transmits ALERT47.

A at the destination ISDN terminal adapter 32
When the LERT 47 is confirmed, the server-side personal computer is made to appear as if there was an incoming call, and an incoming call notification 50 is transmitted to the destination-side personal computer 33. The originating ISDN terminal adapter 30 sends a response message 48 (hereinafter referred to as CONN).
And waits for the establishment of the communication path. The destination ISDN terminal adapter 32 receives the CONN 48, opens the communication path, and confirms that the ISDN terminal adapters 31 and 32 both establish communication path synchronization.
Connection notifications 51 and 52 are transmitted to 33 to notify that data transfer is possible. Based on this information, both personal computers 30 and 33 recognize that data transfer is possible and shift to the communication state.

The operation of the other sequence 2 for realizing the callback function of this embodiment will be described with reference to the sequence chart of FIG.

When making a call back request from the calling side client personal computer 30, the call back request information is added to the end of the called sub address number of the call information 60 and the call is made. The data transmitted by the personal computer 30 is ISDN.
The originating ISDN terminal adapter 3 via the serial interface connected to the terminal adapter 31.
1 is received by the serial interface control circuit 12. The callback function control circuit 14 collates and analyzes the received outgoing call information, and if there is callback request information at the end of the called sub-address in the outgoing call information, the call setup message 61 (hereinafter referred to as SETUP) Callback request information of the destination subaddress is added to the SETU through the ISDN interface control circuit 13.
P41 is transmitted to the ISDN line 20.

In the ISDN terminal adapter 32 of the present invention connected to the called server, the ISDN interface control circuit 13 causes the SETUP from the ISDN line.
61 is received. The called-back sub-address is collated and analyzed by the callback function control circuit 14 via the call control circuit 11. If there is specified callback request information at the end of the called subaddress, the originating ISDN terminal adapter 3
Since 1 requests the callback function, the callback function control circuit 14 stores the subscriber number of the caller in the SETUP 61 in the memory 10. The call message 62 (hereinafter referred to as ALERT) is sent by the call control circuit 11 to S.
It is transmitted to the ISDN line 22 to notify the caller that the ETUP 61 has been normally received. Further, in order to notify the personal computer 33 that there is an incoming call, an incoming call notification 70 is transmitted via the serial interface 23.

When the response information 71 is received from the personal computer 33, a response message 63 (hereinafter referred to as CONN) is transmitted to the ISDN line 22 in response to the incoming call and waits for establishment of a communication path.

The originating ISDN terminal adapter 31 is
When CONN 63 is received, it is determined that the receiving side has received the callback function, and the communication path is connected to establish synchronization.

When the establishment of synchronization can be confirmed, the connection notifications 72, 7 are sent to the personal computers 30, 33 connected respectively.
3 is transmitted to notify that the communication path has been established. By this notification, the personal computers 30 and 33 shift to the communication state and perform data transmission / reception. Here, the client side and the server side mutually perform an authentication procedure such as a user ID and a password.

The originating ISDN terminal adapter 31 is
The callback function control circuit 14 sends the DISC 64 to the ISDN line 20 so that the callback function control circuit 14 temporarily disconnects the communication path according to an instruction from the serial interface control circuit 12, which is confirmed by the non-communication monitoring function that data communication is not performed for a certain period of time. . The receiving ISDN terminal adapter 32 once closes the communication path by the received DISC 64, and then RELE
After confirming that the communication call has been released by ASE65 and RELCOM66, the destination ISDN terminal adapter 32
From the originating ISDN terminal adapter 31 to SETUP
67 is transmitted. However, at this time, both PCs 3
0 and 33 are not notified that the communication is disconnected, and the communication is temporarily stopped by the flow control (flow stop state).

The originating ISDN terminal adapter 31 is C
After sending ONN69, connecting the communication path and confirming the synchronization establishment with both ISDN terminal adapters 31 and 32, cancel the flow stop state instructed to the respective PCs 30 and 33, and perform normal data communication. To notify.

Further, in order to prevent the server side from supporting the callback function of this function for an unspecified number of users, the server side IS that has received SETUP41 of sequence 1 in FIG. 3 and SETUP61 of sequence 2 in FIG.
In the DN terminal adapter 32, it is also possible to collate the caller number in the callback function circuit 14 and to respond only to a callback request from a specific user registered in advance by the identification and reception function. .

By the procedures of sequence 1 and sequence 2 described above, the personal computer 30 of the originating client can transmit and receive data to and from the server side by charging the communication fee of the terminating server.

[0034]

The first effect is that when a call is made from the calling client to the called server, the called server redials the calling server, so that the communication fee is charged to the called server. The reason is that the communication fee is charged to the sender.

The second effect is that it is possible to decide whether or not to connect by collating and analyzing the caller number sent from the calling client at the receiving server, and solving the security problem. You can

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a block diagram showing a connection between a personal computer and the ISDN terminal adapter of FIG.

FIG. 3 is a sequence diagram showing an example of a first sequence of a calling side client and a called side server in the embodiment of the present invention.

FIG. 4 is a sequence diagram showing an example of a second sequence of the calling side client and the called side server in the embodiment of the present invention.

[Explanation of symbols]

1 ISDN Terminal Adapter 11 Call Control Circuit 12 Serial Interface Control Circuit 13 ISDN Interface Control Circuit 14 Callback Function Control Circuit 15 Personal Computer (hereinafter referred to as Personal Computer) 20 ISDN Line 21 Serial Interface 22 ISDN Line 23 Serial Interface 30 Originating Client PC 31 Origin ISDN terminal adapter 32 Destination ISDN terminal adapter 33 Destination server PC

Claims (1)

[Claims] 1. The ISDN terminal adapter 1 is an ISD.
A call control circuit for controlling the communication protocol of the N line, and an IS
Connect to a DN line to transfer messages and data I
The SDN interface control circuit, the interface control circuit having a non-communication monitoring function for performing signal line control and data transmission / reception control with a personal computer, and monitoring a state in which data during data transfer is not transmitted / received for a certain period of time; It has a function of reading the subscriber number from the incoming call setup message and an identification function of identifying whether or not the subscriber number registered in advance and the subscriber's subscriber number read from the call setup message match. An ISDN terminal adapter comprising a callback function control circuit having the same, and a memory for holding a subscriber number of a caller and a subscriber number for identifying the caller in order to realize the call back function.