KR19990006502A - Method and device for multi-frequency code (MFC) tone dial signal security of telephone - Google Patents

Abstract

The present invention relates to an MFC tone dial signal security system of a telephone. In particular, when using a phone banking service provided by a bank or a card company using an MFC telephone, an MFC tone dial signal output from the telephone is encrypted without being transmitted as it is. By transmitting, the user's important information is prevented from leaking when using a phone banking service or the like to improve the reliability between the bank (or the card company) and the customer.

To this end, when the MFC tone corresponding to a special number is detected at the transmitting side or a specific key input condition is detected at the outside, the present invention generates a random random number to establish a telephone line network. Executes mutual authentication for the sending / receiving side by calculating a plurality of authentication function values based on the random number generated by the mobile station, the received random number, the received random number, and a separate preset authentication value. Making; If the MFC tone dial signal is generated at the transmitting telephone, decoding the signal and performing a function conversion to encrypt the signal; A method for securing MFC tone dial signal of a telephone, comprising: converting the encrypted result back to a normal tone different from the MFC tone dial signal generated in an actual telephone to transmit the encrypted result to a telephone dial number; Encryption setting means for detecting a specific condition for encrypting the MFC tone dial signal; Telephone line switching means for switching the signal transmission path between the extension line and the trunk line leading to the telephone by a switching operation; It generates a random number by itself and transmits or receives it through a telephone line network, and calculates a plurality of authentication function values using the random number generated by the user and the received random number and a separate preset authentication value, and compares the result of the calculation. Encryption module mutual authentication means for performing mutual authentication on the sending / receiving side; Encryption means for converting the MFC tone dial signal generated at the push button of the telephone by using an arbitrary encryption function; When a specific condition is detected while the telephone line network of the transmitting side and the receiving side is connected, the encryption module mutual authentication means is controlled to determine whether the transmitting side and the receiving side match, and as a result, the encryption means and the telephone line switching means are determined. And an MFC tone dial signal security device comprising main control means for controlling the MFC tone of the telephone to be transmitted encrypted.

Description

Method and device for multi-frequency code (MFC) tone dial signal security of telephone

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an MFC tone dial security system generated in a multi-frequency code telephone, and is particularly an automatic answering system (hereinafter referred to as ARS) provided by a bank or a credit card company (hereinafter referred to as ARS). In the case where the bank account number (or card number), password, and transaction amount must be transmitted in order to transfer funds using a method telephone, the MFC tone dial signal output from the telephone is encrypted. By encrypting and transmitting the data, the receiving side can decode and recognize the encrypted MFC tone dial signal, thereby preventing user information from leaking when performing money transfer business (phone banking) using an MFC phone, thereby illegally recording the data. It is possible to minimize the damage of the customer due to the mutual authentication between the encrypted transmission module By the through to decrypt the encrypted MFC-tone dial signals to the legitimacy that the verification signal, the present invention relates to the MFC dial tone signal security system telephone that can improve the reliability between the bank (or credit card company) and the customer.

In current MFC telephones, the MFC tone selected by the user at the push of a button and sent to the automatic exchange is a sine wave of two frequencies set in each row and column of the 3x4 or 4x4 key matrix of the voice frequencies generated when the pushbutton dial is pressed. Is a mixed signal, and is considered to prevent malfunction when receiving two frequencies.

In addition, since the dial operation is simple, the transmission speed of the selection signal is high, and the signal can be directly transmitted from one terminal to another terminal through a telephone line network, it is usefully used for various new services.

In particular, banks and credit card companies reduce the cost of manpower and space when handling other transfers, money transfers, deposits and withdrawals, etc. Phone banking services are provided to allow general customers to transfer funds.

In such a phone banking service, an automatic answering system is provided in a host computer such as a bank or a credit card company. The user of the phone banking service calls a telephone number designated by a bank or a credit card company and guides the automated answering system to be transmitted through a telephone line network. In some cases, banking can be performed by pressing the corresponding button on the phone.

In the case of using the phone banking service, banking services such as bank transfer or other funds transfer, deposit balance check, or deposit confirmation, which were possible only by going directly to a conventional bank, can be easily performed using only an MFC phone. In addition to significant time savings, remittance fees are also low, making them widely available to the average customer.

However, when using an automatic answering system of a bank or a card company as an MFC phone as described above, since the MFC tone dial signal generated from the phone is transmitted as a pure MFC tone signal itself to the bank or card company through the telephone line network, the customer information is secured. In the case of illegal recording by another person in the middle of a telephone line, the customer's bank usage information is leaked very easily, and the customer's bank usage information is stolen by others and caused great damage. There was a problem such as being released.

Therefore, the present invention was created to solve the above problems, and the present invention encrypts the MFC tone dial signal output from the MFC-type telephone through an encryption transmission module and transmits it through a communication line, and the receiving side encrypts the encrypted MFC tone dial. By deciphering and recognizing the signal, minimizing damage to customers by illegal recording by preventing leakage of user information when conducting money transfer (phone banking) provided by banks or credit card companies using MFC phones It is also possible to improve the reliability between the bank (or card company) and the customer by allowing the encrypted transmission module to decrypt the encrypted MFC tone dial signal with respect to the signal verified through mutual authentication procedure. To provide a method and apparatus for securing a MFC tone dial signal for a telephone The.

One embodiment of the present invention for achieving the above object is that if the MFC tone corresponding to a special number is detected at the transmitting side or a specific key input condition is detected at the outside in a state in which the telephones of the transmitting / receiving side are connected to make a call. It generates random numbers and transmits or receives them through the telephone line network, calculates a plurality of authentication function values based on the random number generated by itself and the received random numbers and separate preset authentication values, and compares the result of the calculation. Executing mutual authentication for a receiving side; If the MFC tone dial signal is generated in the transmitting telephone, decoding the signal and encrypting the function by converting the function or by converting the table; In order to match the encrypted result with the telephone dial number, the MFC tone dial signal security method of the telephone comprising the steps of reconverting back to normal tone different from the MFC tone dial signal generated in the actual telephone and transmitting it through the telephone line network. do.

Another embodiment of the present invention to achieve the above object is encryption setting means for detecting a specific condition for encryption of the MFC tone dial signal; Telephone line switching means for switching the signal transmission path between the extension line and the trunk line leading to the telephone by a switching operation; It generates a random number by itself and transmits or receives it through a telephone line network, and calculates a plurality of authentication function values using the random number generated by the user and the received random number and a separate preset authentication value, and compares the result of the calculation. Encryption module mutual authentication means for performing mutual authentication on the sending / receiving side; Encryption means for converting the MFC tone dial signal generated at the push button of the telephone using a designated encryption function or a designated table conversion table; When a specific condition is detected while the telephone line network of the transmitting side and the receiving side is connected, the encryption module mutual authentication means is controlled to determine whether the transmitting side and the receiving side match, and as a result, the encryption means and the telephone line switching means are determined. An MFC tone dial signal security apparatus for a telephone is provided, which includes main control means for controlling the MFC tone of the telephone to be transmitted in an encrypted manner.

1 is a block diagram schematically showing an embodiment of a state in which an MFC tone dial signal security system of a telephone according to the present invention is applied;

FIG. 2 is a diagram illustrating an encryption module of FIG. 1 in detail. FIG.

3 is a flowchart illustrating an MFC tone dial signal security method according to the present invention.

4 is a flowchart illustrating a mutual authentication process with a counterpart module executed in the encryption module 1 of FIG. 1.

FIG. 5 is a flowchart illustrating a mutual authentication process with a counterpart module executed in the encryption module 2 of FIG. 1.

** Explanation of symbols for the main parts of the drawings **

10: phone 20A, 20B: encryption module

21: telephone line switching unit 22A; MFC tone detector

22B: key input section 23: power supply section

24: encryption means 24A: MFC tone decoder

24B: encryption operation unit 24C: MFC tone encoder unit

25: encryption module mutual authentication unit 26: main control unit

30: host computer

Hereinafter, the configuration of the MFC tone dial signal security method and apparatus of the telephone according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram schematically showing an embodiment in which an MFC tone dial signal security device of a telephone according to the present invention is applied, and generates an MFC tone dial signal corresponding to a push button input. 10); It is connected between the telephone line and the trunk line to decode the signal transmitted from the trunk line and checks whether it is authenticated with the other party's device.If the verification is confirmed, the MFC tone dial signal output from the MFC-type telephone is encrypted and transmitted to the trunk line. It can be configured as the encryption module 1 (20A).

When the ring signal is transmitted through the arbitrary telephone line network, the host computer recognizes the ring signal transmission status and connects the answering machine. The MFC tone dial signal following the guidance of the answering machine conforms to the rule through the telephone line. When received, the host computer-driven program is set up to run the phone banking service specified by the MFC tone dial signal (for example, the automatic transfer of the desired amount from the user's account number specified by the MFC tone dial signal). The configuration of the host computer 30 in which another encryption module 2 (20B) is mounted in the same form as the encryption module 1 is shown.

FIG. 2 is a diagram illustrating the configuration of the encryption module 1 or 2 of FIG. 1 in detail.

In the drawing, the signal transmission path between the telephone and the trunk line is provided with a path for directly transmitting the MFC tone output of the telephone to the trunk line, and a separate MFC tone dial signal encryption path, respectively. Regardless of the purpose of the present invention, a telephone line switching means 21 is provided for automatically switching the switching terminal according to a control signal generated internally to select one of the two signal transmission paths. At this time, it is also preferable that the telephone line switching means is provided externally between the extension line and the trunk line of the telephone.

In addition, as an encryption setting means for detecting a specific condition in order to perform encryption of the MFC tone dial signal, an MFC tone dial signal, particularly a special button (for example, a * button or a # button), which is directly connected to the telephone extension of the telephone and generated from the telephone, is executed. And an MFC tone detection unit 22A for detecting a dial signal for the < RTI ID = 0.0 >), and a key input section 22B having a switch for manually switching the telephone line switching means manually according to the user's intention.

In addition, as a means for performing mutual authentication on the sending / receiving side, a random random number is generated by itself and transmitted through the telephone line network, or a random number generated by the other party and the result calculated by the other party for mutual authentication are transmitted through the telephone line network. And one or more authentication function values can be calculated using the random number generated by the user, the received random number, and a separate preset authentication value, and comparing the calculation result with the calculation result received through the telephone line network. An encryption module mutual authentication unit 25 for performing mutual authentication is included.

As an encryption means 24 for converting the MFC tone dial signal generated by the telephone according to a specified encryption function or a table conversion table, an MFC tone decoder for decoding the MFC tone dial signal generated by the actual telephone into a corresponding key number. An encryption operation unit 24B for encrypting (for example, hexadecimalizing) the unit 24A and the MFC tone decoding output by using an arbitrary encryption function (which can use various encryption functions set in advance by appointment). And an MFC tone encoder section 24C which reconverts the encrypted signal into a normal MFC tone distinct from the MFC tone dial signal output from the actual telephone to correspond to the dial number of the telephone having high line transmission characteristics. It is configured to include. In the above description, the cryptographic operation unit 24B may have any cryptographic function, which may for example use a known cryptographic function or a separately designed cryptographic function, and even each function may be a separate function or the same. have.

Here, the method of mapping the encrypted signal back to the telephone dial number may convert the encryption result into a decimal number and correspond to the dial number (0-9), and convert the encryption result into a binary number to convert two dial numbers (for example, For example, 0,1 or 0,9) can be used.After converting the encryption result to the lower and upper 4 bits of the hexadecimal number, 0-9 is normal tone, and special buttons (*, #) until AF. One or more of these can be added before or after, and there can be more.

In addition, it has a power supply means 23, and when a specific condition is detected while the telephone line network of the transmitting side and the receiving side is connected, the encryption module mutual authentication unit is controlled to determine whether the transmitting side and the receiving side match. As a result, it comprises a main control means 26 for controlling the encryption means and the telephone line switching means so that the MFC tone of the telephone is transmitted encrypted.

3 is an operation flowchart illustrating a method for securing an MFC tone dial signal according to the present invention, and in particular, in the drawing, a specific condition for transmitting a dial signal encrypted transmission is detected at the transmitting side while the transmitting / receiving side telephone is connected to make a call. (S31-S33) and, if the specific condition is detected, generates a random number by itself and transmits or receives it through a telephone line network, and generates a plurality of random numbers generated by itself and the received random number and a separate preset authentication value. Calculating and verifying an authentication function value, and performing mutual authentication on the transmitting / receiving side (S34, S35), and converting a signal transmission path into an encrypted transmission path according to the authentication verification result. Converts and transmits a series of conversion, encryption, reconversion and transmission of the MFC tone dial signal generated by the transmitting telephone, or an encryption module MFC tones of the telephone comprising the steps of outputting a message indicating that the two do not match with each other (S36, S37), and automatically recovering the signal transmission path (S38, S39) to a path for transmitting normal MFC tones when the call is terminated. A dial signal security method is shown.

Here, an example is shown in which the transmitting / receiving side authentication execution step is initiated by satisfying the condition that the MFC tone corresponding to the special number is detected in the transmitting telephone or the specific key input from the outside is satisfied.

In this reconversion and transmission step, the encrypted result can be converted to decimal to correspond to the dial number of the phone. Alternatively, the lower and upper four bits of the hexadecimal number are converted into normal tones from 0-9. Up to AF may be reconverted by adding at least one special number to the dial number defined up to AF, or may be converted to binary numbers and then used two dial numbers corresponding thereto.

FIG. 4 is a flowchart illustrating an embodiment of a mutual authentication process with a counterpart module executed in the encryption module 1 of FIG. 1, wherein a transmitting side first generates a first random number RA and transmits the same to a receiving side. In step S401-S404, when the second random number and the calculation result are received from the receiving side, the transmitting side uses the second random number, the first random number it has, and its own authentication value. ( F _X ) And if the calculation result VP matches the calculation result VB received from the receiving side, the second authentication function F _Y Step (S405-S412) of recalculating and transmitting to the receiving side and waiting for receiving, and receiving an authentication confirmation signal from the receiving side, and confirming that the encryption module of the receiving side matches with the receiving side as a result of checking the authentication confirmation signal. Recognizing step S413 is included.

FIG. 5 is a flowchart illustrating a mutual authentication process with a counterpart module executed in the encryption module 2 of FIG. 1. When a first random number is received from the transmitting side as shown in the figure, the receiving side receives a second random number. (RB) to generate a first authentication function with its own authentication value AK and the first random number F _X ), And transmitting the calculated result VB and the second random number back to the transmitting side (S511-S517) and receiving the second authentication function calculation result from the transmitting side, when the receiving side receives the second authentication function calculation result. 2 Authentication function ( F _Y ) Is calculated again, and if the calculation result coincides with the second authentication function calculation result received from the transmitter, an authentication confirmation signal indicating that the encryption module installed on the transmitter / receiver is identical is transmitted to the transmitter and the encrypted dial signal. It waits for receiving (S518-S521).

The operation of the present invention as described above is as follows.

First, in the main control means 26 of the encryption module 1 (20A) on the telephone side according to the present invention, when the telephone line network is connected to communicate with a host computer such as a bank or a card company, a special number in the transmitting telephone 10 By detecting the state of the specific key input in the MFC tone or the external key input unit 22B corresponding to (#, *), and if any one is detected, the cryptographic module mutual authentication unit 25 is satisfied by satisfying the specific condition. A transmission / reception side authentication execution step with another encryption module 2 (20B) connected to the bank side host computer 30 is started.

In the authentication execution step, the encryption module 1 (20A) generates a first random number (RA) and transmits it to the host computer 30 of the bank using the normal tone. At this time, if the encryption module 2 (20B) of the host computer 30 receives the first random number (RA), the encryption module 2 (20B) generates a second random number (RB) by itself, and then the authentication key defined in advance with the first random number (RA). (AK) to use the first authentication function ( F _X (RA, RB, AK) ) Is calculated and the result (VB) and the second random number are combined and transmitted to the encryption module 1 (20A) using normal tones.

Therefore, the encryption module 1 20A generates two random numbers that have been fed back, that is, generated by the first random number RA and the host computer-side encryption module 2 20B generated and transmitted to the host computer-side encryption module 2 20B. Using the second random number (RB) sent to the self and the previously stored authentication key (AK), the first authentication function ( F _X (RA, RB, AK) ) Is calculated and the result VP is compared with the result VB transmitted from the host computer side encryption module 2 (20B). If the comparison result is the same, the second authentication function (2) is used again using two random numbers and an authentication key. F _Y (RA, RB, AK) ) And transmits the result VPx to the host computer-side encryption module 2 (20B). If the result is not the same, the comparison error signal or no signal is sent, and the operation is terminated.

The host computer side encryption module 2 (20B) uses two random numbers and a key for authentication again to obtain a second authentication function ( F _Y (RA, RB, AK) ) And compares the result (VBx) with the transmitted result (VPx) and if it is the same, sends an authentication confirmation signal to encryption module 1 (20A). Will end.

Therefore, in the main control means 26 of the encryption module 1 (20A), when the authentication confirmation signal is confirmed, the switching terminal of the telephone line switching unit 21 is connected to the encryption transmission path, whereby the MFC tone dial signal generated by the telephone is MFC. Encryption function or designated table conversion table in which the bank account number, password and amount information of the customer have already been promised to each other by being sequentially transmitted through the decoder unit 24A, encryption operation unit 24B, and MFC tone encoder unit 24C. After encrypting the data, the transmission characteristics are reconverted into good normal tones and transmitted again. The encryption module 2 (20B) on the host computer 30 decrypts the signal through the reverse conversion process to decrypt the customer's bank account number and secret. Number and amount information can be recognized.

According to the present invention as described above, the MFC tone dial signal output from the phone is encrypted and transmitted through an encryption transmission module, and the receiving side decrypts and recognizes the encrypted MFC tone dial signal, thereby transferring funds using the MFC phone. There is an advantage that can prevent the leakage of user information when performing business (phone banking).

Claims (16)

Converting and encrypting the dial signal when the MFC tone dial signal is generated from the calling telephone while the calling / receiving telephone is connected to make a call; And converting the encrypted result back to the normal tone different from the MFC tone dial signal generated in the actual telephone to correspond with the dial number of the telephone and transmitting it through a telephone line network. The mobile station of claim 1, wherein when a specific condition is detected from the sender's telephone, a random number is generated by itself and transmitted or received through a telephone line network. And performing mutual authentication for the transmitting / receiving side by calculating at least one authentication function value and comparing the result of the calculation before the encryption step. . The method according to claim 1, wherein the encryption step of the MFC tone dial signal is executed by an encryption function conversion or an encryption table conversion. 4. A method according to claim 1 or 2 or 3, further comprising the step of decoding the MFC tone dial signal prior to converting the MFC tone dial signal generated at the transmitting telephone into an arbitrary encryption function. How to secure MFC tone dial signal of a telephone. 4. A method according to claim 1, 2 or 3, wherein the result of the reconversion and transmission is reconverted to decimal in order to correspond to a telephone dial number. The method according to claim 1 or 2 or 3, wherein the encrypted result is converted into the lower and upper four bits of the hexadecimal number in the reconversion and transmission steps, and then converted into normal tones from 0 to 9, and until AF. MFC tone dial signal security method of a telephone, characterized in that by adding at least one or more special numbers to the dial number defined up to AF and reconvert. 4. The MFC tone of a telephone according to claim 1, 2, or 3, wherein after converting the encrypted result to a binary number in the re-transforming and transmitting step, two dial numbers corresponding to the converted numbers are used. How to secure dial signal. The transmitting / receiving side authentication execution step is initiated by satisfying the condition that the MFC tone corresponding to a special number is detected in the transmitting telephone or that there is a specific key input from outside. How to secure MFC tone dial signal of a telephone. 9. The method of claim 2 or 8, wherein the transmitting / receiving side authentication step comprises: generating a first random number (RA) at a transmitting side connected through a telephone line network and transmitting the first random number (RA) to a receiving side; The receiving side, which receives the first random number from the transmitting side, generates a second random number RB to generate a first authentication function together with its own authentication value AK and the first random number. F _X ) And transmitting the calculation result VB and the second random number back to the transmitting side; The transmitting side, which has received the second random number and the calculation result from the receiving side, uses the second random number, the first random number that it has, and its own authentication value to generate a first authentication function ( F _X ) And recognizing that the encryption module with the receiving side matches if the calculation result VP and the calculating result (VB) received from the receiving side match. 10. The method according to claim 9, wherein the transmission side receives a calculation result VB input from the reception side and a first authentication function calculated by itself. F _X ) If the two values match, the second authentication function ( F _Y ) Is calculated and transmitted to the receiving side, and the receiving side receiving the second authentication function calculation result from the transmitting side receives the second authentication function ( F _Y ) Is calculated again, and if the calculation result coincides with the second authentication function calculation result input from the transmitting side, transmitting an authentication confirmation signal indicating that the encryption module installed at the transmitting / receiving side is identical to the transmitting side; And a step of recognizing that the encryption module is identical to the receiving side as a result of the checking of the authentication acknowledgment signal at the transmitting side which has received the authentication acknowledgment signal from the receiving side. Encryption setting means for detecting a specific condition for encrypting the MFC tone dial signal generated in the telephone; Telephone line switching means for selectively switching a path for outputting the MFC tone dial signal by a switching operation; It generates a random number by itself and transmits or receives it through a telephone line network, and calculates a plurality of authentication function values using the random number generated by the user and the received random number and a separate preset authentication value, and compares the result of the calculation. Encryption module mutual authentication means for performing mutual authentication on the sending / receiving side; Encryption means for selectively being connected on the MFC tone dial signal transmission path by a switching operation of the telephone line switching means to receive the MFC tone dial signal, encrypting the input MFC tone dial signal and transmitting the same to the trunk line; When the specific condition is detected while the telephone line network of the transmitting side and the receiving side is connected, the encryption module mutual authentication means is controlled to determine whether the transmitting side and the receiving side match, and as a result, the MFC tone dial signal is encrypted. And a main control means for controlling said telephone line switching means and an encryption means to be transmitted in a state. 12. The MFC tone dial signal security device of a telephone according to claim 11, wherein said telephone line switching means is provided externally between an extension and a trunk line of the telephone. 12. The MFC tone dial signal security device for a telephone according to claim 11, wherein said encryption setting means comprises an MFC tone dial signal detection circuit for a special button outputted from the transmitting telephone. 12. The MFC tone dial signal security device of a telephone according to claim 11, wherein said encryption setting means is an external key input means for arbitrarily manually switching said telephone line switching means. 12. The apparatus of claim 11, wherein the encrypting means comprises: MFC tone decoding means for decrypting an MFC tone dial signal with a corresponding key number; Encryption calculation means for encrypting the output of the MFC tone decoding means using a designated encryption function; And an MFC tone encoding signal for converting the output of the encryption calculating means into a normal MFC tone different from the MFC tone dial signal output from the actual telephone. 15. The MFC tone dial signal security device of a telephone according to claim 14, wherein said encryption calculating means encrypts the output of said MFC tone decoding means using a designated table conversion function.