KR102342354B1 - The Method for Non-face-to-face Identification utilizing the Shared-ID and the Convenient-Safe-OTP - Google Patents

Abstract

The present invention is to reduce the inconvenience of carrying an accredited certificate and OTP terminal according to the 'conventional non-face-to-face authentication method using an accredited certificate and hardware OTP' and the inconvenience of having to memorize a lot of information and complicated manual work. While installing the simple safety OTP module, the OTP function unique code and user organization password are encrypted using the master password as the encryption key, and the encrypted OTP function unique code is stored in the OTP function unique code storage unit, and user identification information and encrypted user organization password are stored. storing the secret information to match each other in the DB; Thereafter, when performing non-face-to-face transactions, inputting transaction information and a master password into the user terminal; calculating a shared random value by a random value calculating unit; The decryption function decrypts the 'encrypted, OTP function unique code and user organization password' using the master password as a decryption key; simple safety OTP calculation function calculating OTP using OTP function unique code, user organization password, and shared random value; transmitting, by the user terminal, user identification information and OTP as a reply matched with the transaction information to a user organization server; retrieving 'OTP function unique code and user organization password' matched with the user identification information in the user organization server; calculating a shared random value by a random value calculating unit; calculating OTP by substituting the OTP function unique code, user organization password, and shared random value into the simple safety OTP calculation function; determining whether the identity verification unit matches the 'calculated OTP' with the 'received OTP'; includes

Description

{The Method for Non-face-to-face Identification utilizing the Shared-ID and the Convenient-Safe-OTP}

The present invention relates to a technology for authenticating a person in a non-face-to-face transaction.

In conventional non-face-to-face transactions that require advanced identity authentication technology, such as online remittance of a certain amount or more, an accredited certificate and an 'OTP terminal in the form of a separate hardware from the user terminal (hereinafter referred to as "HOTP terminal") are used repeatedly as a means of authentication. have.

On the other hand, in the conventional self-authentication method using a public certificate (hereinafter referred to as the "authentication method"), the user uses a 'password set by himself/herself' It takes advantage of the feature of the public certificate that it is possible to transmit the 'accurate result value', the accredited certificate result value, to the user organization server if the accredited certificate password is correctly entered. It is possible to infer whether the person who possesses the certificate creation information issued by the user and can accurately know the public certificate password, which is the 'password set by the legitimate user.' However, there is a risk that a person who illegally acquired the result value of the accredited certificate in the process of transmitting the result value of the accredited certificate by a legitimate user in the past stored the result value of the accredited certificate and transmitted it this time (hereinafter referred to as "result value hacking risk") ) cannot be excluded.

On the other hand, in the conventional self-authentication method using HOTP terminals (hereinafter referred to as "HOTP method"), the 'OTP function unique code, which is one of the independent variables configured in the OTP calculation function stored in the HOTP terminal' is the OTP stored in each HOTP terminal. Since the function-specific codes are different from each other, the characteristic of the HOTP terminal is used in that it is possible to calculate and transmit the correct OTP to the user organization server only when possessing a 'HOTP terminal granted to a legitimate user'. However, since the 'correct result value OTP' is different for each identity authentication, the person who illegally acquired the information in the process of transmitting the 'OTP result value of a legitimate user in the past' stores the information and transmits the information this time is not recognized as an accurate OTP, so there is no “risk of result value hacking”. Therefore, the user organization server can be sure of 'whether the person who sent the transaction information is the person who has the HOTP terminal granted to the legitimate user'. However, in exceptional cases, there is a risk that the HOTP terminal is lost or stolen by a legitimate user, and that a third party who acquired or stole the HOTP terminal operates the HOTP terminal and transmits the calculated OTP (hereinafter "terminal theft risk") ) cannot be excluded.

On the other hand, in the conventional self-authentication method that transmits both the public certificate result value and the 'OTP generated by the HOTP terminal' (hereinafter referred to as the "authentication certificate & HOTP method"), the accurate public certificate result value and the correct OTP are transmitted even though both are transmitted. If one person is not a legitimate user, the exception is that 'a person who illegally acquired the result value of the accredited certificate in the process of transmitting the result value of the accredited certificate by a legitimate user in the past' stores the result of the accredited certificate and transmits the result this time. This is an extremely exceptional case (i.e., "risk of result hacking" and "risk of terminal theft" being the same illegal user when realized by ), etc. Therefore, a higher level of security is recognized compared to the 'method of sending only one of the official certificate result value and OTP'. For that reason, most domestic banks allow up to '100 million won per case and 500 million won per day' for non-face-to-face transactions using "certified certificate & HOTP method", whereas only one of "certified certificate method" and "HOTP method" is used. For non-face-to-face transactions, only a smaller limit is allowed.

However, in "Authenticated Certificate & HOTP Method", the accredited certificate must be downloaded and stored in the user terminal, and the HOTP terminal must be received and registered in the user organization server. must be carried, memorize both the user organization login password and the accredited certificate password, manually operate the HOTP terminal to generate OTP, and manually input both the user organization login password and the accredited certificate password together with the OTP. Unfortunately, there is a lot of information to memorize and manual work is complicated.

To alleviate this inconvenience, 'Software-type OTP generating module' (hereinafter referred to as "SOTP module") is installed in the user's terminal by replacing the HOTP terminal, and OTP is automatically calculated from the SOTP module when OTP submission is required. A method has been proposed so that the user terminal automatically transmits the OTP to the user organization server. However, according to this method, in the process of downloading the SOTP module to the user terminal, the risk of hacking the 'OTP function unique code configured in the OTP calculation function stored in the SOTP module' (hereinafter referred to as "hacking risk during communication") and the above Even after the module is stored in the user terminal, there is a risk that the OTP function-specific code is hacked in the storage device of the user terminal (hereinafter referred to as "hacking risk during storage"). Therefore, compared to the case of using a HOTP terminal, the security level is lowered. As a method to compensate for this limitation, a method of encrypting the OTP function-specific code and storing it in the user terminal may be proposed. Since the method of decrypting the 'encrypted OTP function unique code' by hacking the decryption key cannot be prevented, the degree of safety is still lower than the method of carrying a HOTP terminal.

The object of the present invention is the inconvenience of carrying the HOTP terminal, the inconvenience of having to separately memorize the user organization password and the public certificate password, and the manual operation of the HOTP terminal in a non-face-to-face transaction that requires "authentication certificate & HOTP method" An object of the present invention is to provide a method for reducing the inconvenience of manually generating an OTP and manually inputting both the user organization password and the public certificate password together with the OTP.

One embodiment of a non-face-to-face self-authentication method using a shared ID and simple safety OTP according to the characteristics of the present invention for solving these technical problems is, while installing a simple safety OTP module in the user terminal, user identification information and inputting the shared ID and master password; calculating an OTP function unique code using the shared ID and shared random value; retrieving an encryption function from the function storage unit and encrypting, by the encryption function, a user organization password and an OTP function unique code using the master password as an encryption key; The encrypted OTP function unique code is stored in the OTP function unique code storage unit, and the user identification information and the encrypted user organization password are stored to match each other in the secret information DB; Thereafter, when performing non-face-to-face transactions, inputting transaction information and a master password into the user terminal; The simple safe OTP calculation function and decryption function are searched in the function storage unit of the user terminal, 'encrypted OTP function unique code' is searched in the OTP function unique code storage unit, and 'user identification information and encrypted user organization password' are searched in the secret information DB ' is searched and the random value calculating unit calculates a shared random value; decrypting, by the decryption function, the 'encrypted OTP function-specific code and encrypted user organization password' as a decryption key for the master password, respectively; calculating the OTP by the simple safety OTP calculation function using 'the decrypted OTP function unique code', 'the decrypted user organization password', and 'the calculated shared random value'; transmitting, by the user terminal, the 'searched user identification information' and 'the calculated OTP' with the 'input transaction information' to a user organization server; when the user organization server receives the 'user identification information, OTP, and transaction information', searching for 'OTP function unique code and user organization password' matching the user identification information in a user DB; a step of searching for a simple safety OTP calculation function in a function storage unit of a user organization server and calculating a shared random value by a predetermined method in a random value calculation unit; calculating OTP by substituting 'the searched OTP function unique code and user organization password' and 'the calculated shared random value' into the simple safety OTP calculation function; and comparing the calculated OTP with the received OTP by the identity authentication unit to determine whether or not there is a match; includes

According to the embodiment, in the OTP function-specific code storage unit of the simple safety OTP module installed in the user terminal, 'OTP function-specific code calculated using the shared ID' is encrypted and stored, and the shared ID is unique for each user. Therefore, the simple safety OTP module installed in each user terminal becomes a unique file for each user, and the user has a 'password set by himself/herself' in the simple safety OTP module file, which is the 'file uniquely issued to himself' If the master password is entered correctly, OTP, which is an 'correct result value', can be transmitted to the user organization server. Therefore, in the above embodiment, in the user organization server, it can be estimated whether the person who transmits the transaction information is the person who has the 'file uniquely issued to the legitimate user' and can accurately know the 'password set by the legitimate user'. be able to However, the above features are the same as those of the "Authenticated Certificate Method". For example, if the user correctly inputs the 'password set by the user' in the 'file uniquely issued to the user', the 'correct result value' can be transmitted to the user organization server.

Also, according to the embodiment, since the OTP function unique code is calculated using 'a different shared ID for each user', the OTP function unique codes stored in each user terminal are different from each other. However, since the OTP function unique code is 'one of the independent variables configured in the OTP calculation function stored in the user terminal', the correct OTP can be calculated and transmitted to the user organization server only when possessing the 'OTP function unique code given to a legitimate user' there will be In addition, there is no "risk of hacking the result value" because the 'correct result value OTP' is different for each user authentication. be able to However, the above features are almost identical to those of the "HOTP method".

In addition, in the above embodiment, since the OTP function-specific code is calculated using the 'shared ID, which is identification information that the user himself can easily identify,' the OTP function is unique in the user terminal without receiving any information from the user organization server. It becomes possible to calculate the code, and there is no need to communicate the OTP function-specific code, so unlike the 'conventional self-authentication method using the SOTP module' (hereinafter referred to as the "SOTP method"), the "risk of hacking during communication" is eliminated. And in the above embodiment, the calculated OTP function-specific code is encrypted and stored at the same time as the calculation, and the key used for encryption is 'not stored anywhere in the world, such as the user terminal as well as the user organization server or the identity authentication authority server, and the user Since it is a 'master password characterized by memorizing it', unlike the "SOTP method", the "risk of hacking during storage" is also eliminated. Therefore, in the above embodiment, unlike the "SOTP method", like the "HOTP method", the user organization server determines whether the person who transmitted the transaction information It possesses the characteristics of being able to be certain, not speculative.

Nevertheless, the above embodiment is an advantage over the "HOTP method". Just by stealing the 'user terminal, which is a device in which the OTP function unique code is stored', the 'stolen transaction of an illegal user' is not mistaken for a 'legal user's transaction'. have non-existent features. The possibility that an illegal user transmits a legitimate result value (OTP) is an extremely exceptional case in which even the master password is exposed to the person who steals the user terminal (that is, "terminal theft risk" and "master password exposure risk" are the same This is because it is limited to the case where it is realized by Taking these characteristics into consideration, the safety of the above embodiment becomes comparable to that of the "Authenticated Certificate & HOTP Method".

More clearly, if we compare the safety of the above embodiment with the safety of the "authorized certificate & HOTP method", the probability that the "terminal theft risk" and "master password exposure risk" will be realized by the same illegal user at the same time (hereinafter referred to as "embodiment risk probability") It is necessary to compare the probability that "terminal theft risk" and "result value hacking risk" will be realized by the same illegal user at the same time (hereinafter referred to as "accredited certificate & HOTP method risk probability"). However, since "terminal theft risk" is included as a common factor in "Example risk probability" and "Certificate certificate & HOTP method risk probability", it is necessary to compare "master password exposure risk" and "result value hacking risk".

However, the master password is 'information that does not need to be stored or exposed anywhere in the world as long as the user memorizes it'. Therefore, if the user is sure to memorize the master password, there is no need to record or store the master password somewhere, so the risk of master password exposure is very low. However, according to the present invention, if only the master password is memorized, the user organization password registered with each user organization is automatically calculated by the simple and secure OTP module, so there is no need for the user to memorize. Therefore, there is only one password that the user has to memorize, the master password. If the password to be memorized is one master password, it is very easy for the user to have confidence in memorizing the master password. Therefore, the probability of realizing the "master password exposure risk" can be controlled very low by the features of the present invention. On the other hand, there is a limit to controlling the probability of a “result value hacking risk” that is a risk of being hacked in the process of transmitting a predetermined result value by a known method.

Therefore, the "master password exposure risk" is easier to control than the "result value hacking risk", so the probability that the "master password exposure risk" will materialize will be smaller than the probability that the "result value hacking risk" will materialize, even if viewed conservatively. It won't be any bigger. That is, even if viewed conservatively, the "Example risk probability" will not be higher than the "Certificate certificate & HOTP method risk probability". Accordingly, it is possible to use the method of the above embodiment in a transaction that requires "authentication certificate & HOTP method".

However, you do not need to carry the HOTP terminal, and if you memorize and input only one master password, you do not have to memorize the user organization password and the public certificate password separately, and you do not need to memorize the user organization password and the public certificate password separately. It is more convenient than "Authenticated Certificate & HOTP Method" as it does not require manual work such as entering

1 is a block diagram of a device required to implement a non-face-to-face authentication method using a shared ID and simple safety OTP, according to an embodiment of the present invention.
2 is a view for explaining an operation of a user installing a simple safety OTP cap on a user terminal according to an embodiment of the present invention.
FIG. 3 is a diagram for explaining an operation for a user to transmit remittance application information as an embodiment of transaction information using a simple and secure OTP module and conveniently authenticate himself according to an embodiment of the present invention.
4 is a diagram for explaining the operation of simple self-authentication while transmitting 'consent information for a predetermined payment consent application' as an embodiment of transaction information by a user using a simple and secure OTP module according to an embodiment of the present invention. It is a drawing.
5 to 8 are diagrams illustrating an output unit of a user terminal that can be exemplified in each step of an operation in which a user conveniently authenticates himself using a simple safety OTP cap according to an embodiment of the present invention.
9 is a diagram illustrating a secret information DB of a user terminal that can be exemplified in one step of an operation in which a user conveniently authenticates himself using a simple and secure OTP module according to an embodiment of the present invention.
10 and 11 are diagrams illustrating a user DB of a user organization server that can be exemplified in each step of an operation in which a user conveniently authenticates himself/herself using a simple safety OTP module according to an embodiment of the present invention.

Hereinafter, the present invention will be described in detail through preferred embodiments described with reference to the accompanying drawings.

Embodiments of the present invention may be variously changed without departing from the spirit and scope of the present invention. The following detailed description is not intended to limit the present invention, and terms used in the detailed description are selected for readability or convenience of description.

In addition, in the present invention, the "shared random value" is a value that is calculated randomly, and is randomly calculated in the same way in the user organization server and the user terminal, and as a result, the user organization server and the user terminal are It means a random value that is equally calculated. A time value output by the timer of the user organization server and the timer of the user terminal, respectively, may be an example of a shared random value under the premise that the time difference between the timer of the user organization server and the timer of the user terminal is negligible.

Also, in the present invention, the term "transaction" refers to monetary transactions such as remittance and payment, and non-monetary transactions such as information retrieval.

Also, in the present invention, "transaction information" refers to 'information to apply for a specific transaction' and 'information to agree to a specific transaction application'. For example, both 'information to apply for a specific remittance (or payment) transaction' and 'information to agree to a specific remittance (or payment) transaction application' may be "transaction information" in the present invention.

In addition, in the present invention, "shared ID" means 'information stored by matching with specific user identification information in the server of the user organization. It is information for identification and means 'information that the user can easily grasp. For example, if the user organization server is a mobile banking server of a specific bank, and the mobile banking server matches specific user identification information, 'Serial Number of the user's HOTP terminal', 'Serial Number of the user's password card', 'The user 'Payment account number', 'the user's mobile phone number', 'the user's e-mail address', etc. are stored, and the user selects the 'Serial Number of the HOTP terminal' and If 'the payment account number', 'the mobile phone number' and 'the e-mail address' can be easily identified, all of the above information can be a "shared ID" between the user and the mobile banking server in the present invention. have.

Also, in the present invention, the term "master password" is a password selected and memorized by a user. It means a password that does not need to be exposed to anyone in the world as well as a user organization, and does not need to be stored anywhere in the world, not to mention the user organization server or user terminal.

Also, in the present invention, "user identification information" means information for identifying a specific user from other users in the user organization server. Accordingly, the user's login ID, account ID, real name number, etc. may be examples of user identification information.

delete

Also, in the present invention, the term "app" means an application program driven by the OS of a specific computing device.

Also, in the present invention, the term "using organization" means a subject operating the "using organization server".

Also, in the present invention, the term "user organization server" refers to a server that a specific user accesses to use a specific service. The identity authentication server that the user accesses to use the identity authentication service, the mobile banking server that the user accesses to use the mobile banking service, the search service server that the user accesses to use the search service, and the e-commerce server that the user accesses for commerce All of them may be an embodiment of the user organization server.

Also, in the present invention, "user organization password" refers to various passwords registered by a specific user with the user organization. Accordingly, the password for the user to log in to the user organization server, the account password that must be submitted to make a transaction using his or her account registered with the user organization, and the certificate password that must be submitted to use the certificate registered with the user organization etc. may be examples of user organization passwords,

Also, in the present invention, "OO box" is an area in which information meaning "OO" is marked among the screen areas output to the output unit, and "OO box" is selected as 'action such as touching or clicking the area'. It means an area configured to input information.

1 is a block diagram of a device required to implement a non-face-to-face authentication method using a shared ID and simple safety OTP, according to an embodiment of the present invention.

Referring to Figure 1, the device required to implement the non-face-to-face personal authentication method using the shared ID and simple safety OTP includes a user authentication server 100, a user organization server 200, and a user terminal 300, each The components 100 , 200 , and 300 may be connected through a wired/wireless network.

The identity authentication server 100 is a computing device that can be connected to one or more of the user organization server 200 and the user terminal 300 and a wired/wireless network, and has an input unit, an output unit, a storage device, an arithmetic unit, and an OS. It includes (110) and a hairline storage unit (120).

In the module issuance DB 110, the user identification information and password of each user who has downloaded the simple safety OTP module is stored by matching with each other.

The module storage unit 120 stores a 'simple safety OTP module in which a default value is stored in the OTP function unique code storage part' (hereinafter referred to as 'easy safety OTP module before issuance').

The user organization server 200 includes a user DB 210, a function storage unit 220, a random value calculation unit 230, and a user authentication unit 240. According to an additional aspect of the present invention, the user authentication server 100 may also serve as the user organization server 200 .

The user DB 210 may store each user's 'user organization password, shared ID, and OTP function unique code' by matching the user identification information of each user. 11 shows an embodiment of the user DB 210 in the case where the serial number of the HOTP terminal is the shared ID.

A simple safety OTP calculation function is stored in the function storage unit 220 . The simple safety OTP calculation function uses 'OTP function unique code and user organization password searched by matching specific user identification information in the user DB 210' and 'shared random value generated by the random value calculation unit 230' to calculate OTP, even though the method of receiving each necessary independent variable (OTP function unique code, user organization password, shared random value) is different, the function itself is 'in the module storage unit 120 of the identity authentication server 100 It is the same as the 'simple safety OTP calculation function stored to calculate OTP' in the function storage unit configured in the stored simple safety OTP module before issuance. According to an additional aspect of the present invention, a copy of the 'simple secure OTP module before issuance stored in the module storage unit 120 of the personal authentication server 100' is downloaded and installed in the user terminal 300, resulting in As such, it becomes the same as the simple safety OTP calculation function stored in the function storage unit configured in the simple safety OTP module 310 installed in the user terminal 300 .

According to an additional aspect of the present invention, the inverse function of the simple safety OTP calculation function is also stored in the function storage unit 220 .

The random value calculation unit 230 is shared random in the same way as the random value calculation unit configured in the 'simple secure OTP module before issuance stored in the module storage unit 120 of the identity authentication server 100' calculates the shared random value. Calculate the value. Retrieving the time value from the timer may be an example of calculating the shared random value.

When the user organization server 200 receives a predetermined authentication target OTP, the user authentication unit 240 compares it with the 'OTP calculated by the simple safety OTP calculation function in the user organization server 200' to determine whether or not it matches.

According to another aspect of the present invention, the identity authentication unit 240, when the user organization server 200 receives a predetermined authentication target OTP, 'the OTP in the inverse function of the simple safety OTP calculation function in the user organization server 200' Matches the 'user organization password calculated by substituting ' with the 'user organization password retrieved from the user organization server 200' to determine whether they match.

According to another aspect of the present invention, the identity authentication unit 240, when the user organization server 200 receives a predetermined authentication target OTP, 'in the user organization server 200, the inverse function of the simple safety OTP calculation function. An encrypted value is calculated by substituting the OTP-calculated user organization password' into a predetermined encryption function, and matching the encrypted value with the 'encrypted user organization password retrieved from the user organization server 200' decide whether

The user terminal 300 may be connected to a wired/wireless network and includes all computing devices having an input unit, an output unit, a storage device, an operation unit, and an OS. In this specification, the case of a smart phone will be exemplified. The simple safety OTP module 310 in the present invention may be installed in the storage device configured in the user terminal 300 , and the module may be driven by the OS configured in the user terminal 300 .

Simple safety OTP module 310 is a program downloaded from the identity authentication server 100, OTP function unique code storage unit 311, secret information DB 312, function storage unit 313, random value calculation unit 314 ) and a reference solution storage unit 315 .

The encrypted OTP function unique code is stored in the OTP function unique code storage unit 311 .

In the secret information DB 312, 'user identification information and an encrypted user organization password' are stored by matching the user organization identification information. Fig. 9 shows an embodiment of the secret information DB 312 in the case where the user organization is one person other than the identity authentication service organization. 9 exemplifies a case in which the user organization is one other than the identity authentication service organization for simplification of explanation, but the number of user organizations can be expanded within the range allowed by the storage capacity.

The function storage unit 313 stores a simple safe OTP calculation function, an encryption function, and a decryption function. The simple safety OTP calculation function uses each independent variable (OTP function unique code, use Although the method of receiving the institutional password and shared random value) is different, the function itself is the same as the simple safety OTP calculation function stored in the function storage unit 220 of the user institution server 200 . The encryption function uses the 'master password inputted to the input unit' as an encryption key to encrypt the 'encryption target information inputted to the input unit'. The decryption function decrypts the 'decryption target information' by using the 'master password inputted to the input unit' as a decryption key.

The random value calculating unit 314 calculates the shared random value in the same way as the random value calculating unit 230 of the user organization server 200 calculates the shared random value.

FIG. 2 is a view for explaining an operation of a user installing a simple safety OTP cap 310 in a user terminal 300 according to an embodiment of the present invention.

In step 210 , the issuance application information for a predetermined simple safety OTP module is received from the user terminal 300 to the identity authentication server 100 .

In step 215, the simple secure OTP module before issuance is retrieved from the module storage unit 120 in the identity authentication server 100, and the simple secure OTP module before issuance is transmitted to the user terminal 300.

In step 230, the simple safety OTP module is installed in the user terminal 300 before issuance, and 'user identification that must be submitted in order to use each user organization service by matching with 'one or more user organization service identification information including personal authentication service' Information and user organization password', each input box and confirmation box for entering shared ID and master password are output. The identification information of the service provided by the user authentication server is 'personal authentication service', the identification information of the service provided by the user organization server is 'Daehan Bank Mobile Banking', and 'the user uses Korea Bank Mobile Banking' as the shared ID. 5 shows an example of an output unit of the user terminal 300 after operation 230 is performed in the case of using the 'Serial Number of the HOTP terminal registered for this purpose.

In step 235, the user inputs user identification information, user password, shared ID and master password in 'each matched input field output in step 230' using the input unit of the user terminal 300, and selects a check box do. In the case exemplified in step 230, the user identification information and user organization password of Korea Bank Mobile Banking that the user is currently using are 'bani75' and '1111', respectively, and the shared ID adopted by the Korea Bank Mobile Banking server is 'HOTP' The serial number of the terminal is '1626', and the serial number specified on the HOTP terminal distributed by Daehan Bank to the user is '1626', and the user selects bani75, which is the same as the login ID of Daehan Bank Mobile Banking, as user identification information to be registered in the user authentication server. As the 'login password that is the user organization password' to be registered in the authentication server, the 'Korea Bank Mobile Banking login password If you select '2321' different from '2321' and memorize '1234' as the master password, the user will select a check box after entering each input box as illustrated in FIG. 6 .

In step 240, an OTP function unique code is calculated using the 'base shared ID input in step 235'. According to an additional aspect of the present invention, in step 240, the random value calculating unit 314 calculates a predetermined random value, and substitutes the base share ID and the random value into a predetermined function to calculate the OTP function unique code. can In the case exemplified in step 235, the base share ID is '1626'. In the above case, the random value calculating unit 314 calculates the current time value as a shared random value, the current time is 8:42, the time value 842 is calculated as a random value, and a function for calculating the OTP function unique code If is 'shared ID + shared random value', '1626 + 842 = 2468' will be calculated as an OTP function unique code. If the function that calculates the OTP function unique code in the above case is 'base share ID', '1626', which is the 'base share ID input in step 235', will be calculated as the OTP function unique code.

In step 245, an encryption function is searched for in the function storage unit 313, and the encryption function uses 'the input master password' as an encryption key, and 'each user organization password input in step 235' and 'OTP function generated in step 240 Encrypt each 'unique code'. In the case exemplified successively in steps 235 and 240, if the encryption function is 'variable to be encrypted + master password', then 'identity authentication server login password 2321 and Korea Bank Mobile Banking server login password 1111 input in step 235' and 'OTP function unique code 2468 generated in step 240' will be encrypted as '2321 + 1234 = 3555', '1111 + 1234 = 2345', and '2468 + 1234 = 3702', respectively. According to another aspect of the present invention, in step 245, 'each user identification information input in step 235' may be encrypted in the same way.

In step 250, the 'OTP function unique code encrypted in step 245' is stored in the OTP function unique code storage unit 311, and the 'user identification information input in step 235' and 'the user identification information encrypted in step 245 and The matched user organization password' is stored in the secret information DB 312 to match each other. In the case exemplified successively in steps 235 to 245, the secret information DB 312 after step 250 is operated is illustrated in FIG. 9 . According to another aspect of the present invention in which 'user identification information input in step 235' is encrypted in step 245, 'user identification information encrypted in step 245' is replaced in step 250 by 'user identification information input in step 235' is saved

In step 255, 'each user identification information for one or more user organization servers including the identity authentication server input in step 235' and 'personal authentication institution password input in step 235' are transmitted to the identity authentication server 100 and 'all information input in step 235' is deleted. According to an additional aspect of the present invention in which other information such as a random value is used in addition to the base shared ID for generating the OTP function unique code in step 240, the random value is also transmitted in step 255. However, when the random value is a shared random value, the shared random value may not be transmitted.

In step 260, the 'received user identification information and password for the identity authentication server' from the identity authentication server 100 match each other and are stored in the module issuance DB 110, and 'received, user identification for the user organization server' Information' is relayed to the user organization server 200 . According to an additional aspect of the present invention in which a random value is transmitted together in step 255, the random value is sent to the user organization server 200 together with matching 'received user identification information for the user organization server' in step 260. is relayed Meanwhile, according to another aspect of the present invention, in step 255, the 'user identification information for the user organization server input in step 235' and the 'random value used in step 240' are transmitted to the user organization server ( 200), and only 'user identification information and password for the self-authentication server input in step 235' may be transmitted to the self-authentication server 100 .

In step 265, when 'user identification information for a user installed with a simple safety OTP module' is received from 'one of the user terminal 300 and the identity authentication server 100' in the user organization server 200, the user DB 210 The shared ID matching the 'received user identification information' is searched for. In the case exemplified in step 235, the 'received user identification information' will be 'bani75', and '1626' which is the 'Serial Number of the OTP terminal' matched with 'bani75 as user identification information' in the user DB 210 This will be searched for. An example of the user DB 210 in this case is as shown in FIG. 10 .

In step 270, the OTP function unique code is generated in the 'same method as in step 240' using the shared ID in the user organization server 200, and the user DB 210 matches the 'received user identification information' Thus, the OTP function unique code is stored. In the case exemplified in step 240, if the calculated random value is a shared random value, the random value calculation unit 230 'random value calculation unit 314 configured in the simple safety OTP module 310 installed in the user terminal 300' ), the current time value will be calculated as a shared random value, 8:42', and 842 as a time value will be calculated as a shared random value. In addition, '1626 + 842 = 2468' is calculated as an OTP function unique code by using 'shared ID + shared random value', which is the 'function as in step 245', and matched to the 'bani75 as user identification information' It will be stored as OTP function unique code. 11 illustrates an example of the user DB 210 after step 270 is operated in the above case. As another aspect of the present invention, in the case where the shared ID itself is generated as an OTP function unique code, storing the OTP function unique code may be omitted in step 270 .

FIG. 3 is a diagram for explaining an operation for a user to transmit remittance application information as an embodiment of transaction information by using the simple and secure OTP module 310 and to conveniently authenticate himself according to an embodiment of the present invention.

In step 325, when the user selects the simple identity authentication box using the input unit of the user terminal 300, a registration/change box, a 'remittance application information input field as an embodiment of the transaction information input field', a master password input field, and a confirmation box are output do. An example of the output unit of the user terminal 300 after operation 325 is shown in FIG. 7 .

In step 335, the user inputs 'remittance application information as an example of information for applying for a specific transaction' in the remittance application information input field using the input unit of the user terminal 300, and enters the master password in the master password field and confirms Select the box. In the case exemplified in step 235, the user memorizes '1234' as the master password, so he will input '1234' in the master password input field.

In step 340, the simple safe OTP calculation function and the decryption function are retrieved from the function storage unit 313, the 'encrypted OTP function unique code' is retrieved from the OTP function unique code storage unit 311, and the secret information DB 312 'User identification information and encrypted user organization password' is searched in , and the random value calculating unit 314 calculates a shared random value in 'the same method as the method for calculating a shared random value in the user organization server' to simplify safety OTP The module identifies the shared random value. In the case exemplified in steps 235, 245 and 9, '3702' is searched for as 'encrypted OTP function unique code', and 'user identification information and encrypted user organization password' are searched in the secret information DB 312, respectively. 'bani75' and '2345' will be searched. As an example in which the random value calculating unit 314 calculates the shared random value in the same way as the method of calculating the shared random value in the user organization server, the calculation of the current time value as a shared random value is an example can do. For example, if the current time is 13:10, '1310' may be calculated as a shared random value.

In step 345, the decryption function decrypts the searched 'encrypted OTP function unique code' and 'encrypted user organization password', respectively, using 'the input master password' as a decryption key. In the case exemplified in step 245, the decryption function will be 'encrypted variable - master password', which is the inverse function of 'variable to be encrypted + master password', which is the 'encryption function illustrated in step 245'. Also, in the case exemplified in step 340, '3702' and '2345' were searched as 'encrypted OTP function unique code' and 'encrypted user organization password', respectively, which are encrypted variables, and if the case exemplified in step 335 '1234' was entered as the master password. Therefore, in the case exemplified successively in steps 245, 335, and 340, '3702-1234 = 2468' and '2345-1234 = 1111' as 'decrypted OTP function unique code' and 'decrypted user organization password', respectively this will be calculated

In step 350, the OTP is calculated by substituting 'the decrypted OTP function unique code', 'the decrypted user organization password' and 'the calculated shared random value' into the simple safety OTP calculation function. In the case continuously illustrated in steps 340 and 345, the 'decrypted OTP function unique code' and 'decrypted user organization password' are '2468' and '1111', respectively, and the shared random value is '1310'. In the above case, if the simple safety OTP calculation function is 'OTP = OTP function unique code + user organization password + shared random value', '2468+1111+1310 = 4889' will be calculated as OTP.

In step 355, the user terminal 300 matches the 'searched user identification information' and 'the calculated OTP' with 'remittance application information as an example of transaction information input in step 335', and the user organization server 200 send to If it is the case exemplified successively in steps 340 and 350, 'bani75 as user identification information' and '4889 as OTP' will be transmitted.

When the user organization server 200 receives the 'user identification information, OTP, and remittance application information as an embodiment of transaction information' in step 360, the 'OTP function matched to the user identification information in the user DB 210' Unique code and user organization password' are searched. In the case exemplified in steps 355 and 270, '2468' and '1111' as 'OTP function unique code and user organization password' matched to 'bani75 as user identification information' in the user DB 210 illustrated in FIG. 11 , respectively ' will be searched for. In the case of the embodiment in which the storage of the OTP function unique code is omitted in step 270, the shared ID matching the 'received user identification information' in the user DB 210 may be searched as 'the OTP function unique code'.

In step 365, the simple safety OTP calculation function is retrieved from the function storage unit 220 of the user organization server 200, and the random value calculation unit 230 calculates a shared random value in a predetermined method to the user organization server 200. determines the shared random value. The random value calculation unit 230 is shared random in the same way as the random value calculation unit configured in the 'simple secure OTP module before issuance stored in the module storage unit 120 of the identity authentication server 100' calculates the shared random value. It has the feature of calculating a value, because a copy of 'simple secure OTP module before issuance stored in the module storage unit 120 of the identity authentication server 100' is installed in the user terminal 300, the user terminal 300 A shared random value is calculated in the same way as in . Therefore, in the case illustrated in step 340, if the time difference between the time at which step 340 is operated and the time at which step 365 is operated is negligible, the random value calculating unit 230 sets a time value corresponding to the current time of 13:10 ' 1310' will be calculated as a shared random value.

In step 370, 'the searched OTP function unique code and user organization password' and 'the calculated shared random value' are substituted into the simple safety OTP calculation function to calculate the OTP. If it is the case continuously illustrated in steps 350, 360 and 365, '2468' and '1111' are searched respectively as 'OTP function unique code and user organization password', respectively, and '1310' will be calculated as a shared random value. Since the simple safety OTP calculation function is 'OTP function unique code + user organization password + shared random value', '2468 + 1111 + 1310 = 4889' will be calculated as OTP.

In step 375, the identity authentication unit 240 compares the 'OTP calculated in step 370' and the 'OTP received in step 360' to determine whether or not there is a match. In the case illustrated in steps 350 and 370, the identity authentication unit 240 will determine that '4889 as the calculated OTP' and '4889 as the received OTP' match. According to an additional aspect of the present invention, when it is determined that a match is made in step 375, the user organization server 200 performs remittance processing according to 'remittance application information as an embodiment of transaction information received in step 360'. do.


On the other hand, according to another aspect of the present invention for the case of one-way encryption and storage of the user organization password using a hash function, etc. so that the user organization server 200 cannot decrypt the user organization password, steps 360 to 375 are as follows: Steps 360-1 to 375-1 may be substituted.

When the user organization server 200 receives the 'user identification information, OTP, and remittance application information as an embodiment of transaction information' in step 360-1, the user DB 210 matches the 'user identification information' OTP function unique code and encrypted user organization password' are searched. In the case exemplified in steps 355 and 270, '2468' and '1111' respectively as 'OTP function unique code and encrypted password' matched to 'bani75 as user identification information' in the user DB 210 illustrated in FIG. 11 . This encrypted value' will be retrieved. In the case of the embodiment in which the storage of the OTP function unique code is omitted in step 270, the shared ID matching the 'received user identification information' in the user DB 210 may be searched as 'the OTP function unique code'.

In step 365-1, the 'inverse function of the simple safety OTP calculation function for calculating the user organization password' is searched for in the function storage unit 220 of the user organization server 200, and the random value calculation unit 230 uses a predetermined method. By calculating a shared random value, the user organization server 200 identifies the shared random value. If the simple safety OTP calculation function is as exemplified in step 350, the inverse function of the simple safety OTP calculation function for calculating the user organization password will be 'user organization password = OTP - OTP function unique code - shared random value'. The characteristics of the random value calculating unit 230 are the same as in step 365 .

In step 370-1, 'the received OTP', 'the searched OTP function unique code', and 'the calculated shared random value' are substituted into the inverse function of the simple safety OTP calculation function to inversely calculate the user organization password. If it is the case exemplified successively in step 355, step 360-1 and step 365-1, '4889' will be received as OTP, '2468' will be searched as OTP function unique code, and '1310' will be a shared random value. will be calculated, and since the inverse function of the simple safety OTP calculation function is 'OTP - OTP function unique code - shared random value', '4889 - 2468 - 1310 = 1111' will be calculated as the user organization password.

In step 375-1, the identity authentication unit 240 determines whether the 'encrypted user organization password retrieved in step 360-1' and the 'user organization password calculated in step 370-1 match'. In the case illustrated in steps 360-1 and 370-1, the user authentication unit 240 encrypts the user organization password to store '1111 as the calculated user organization password' in the user DB 210. Calculate the encrypted value by substituting for ', and compare the '1111 encrypted value' with the '1111 encrypted value' found in step 360 to find out that they match, and determine that both match each other will be. An additional aspect in step 375 is the same as in step 375-1.

4 is an operation in which a user transmits 'consent information for a predetermined payment agreement application' as an embodiment of transaction information using the simple and secure OTP module 310 and conveniently authenticates the user according to an embodiment of the present invention. is a diagram for explaining

In step 410, when the user terminal 300 receives 'consent application information for a predetermined payment as an example of information for requesting a specific transaction' transmitted from the predetermined user organization server 200, the simple safety OTP module 310 is driven to output 'the received payment consent application information' together with a predetermined confirmation box and a rejection box to the output unit.

8 is a diagram illustrating an output unit of the user terminal 300 after operation 410 is performed.

In step 420, when the user inputs consent information by selecting a check box using the input unit of the user terminal 300, the reference solution stored in the reference solution storage unit 315 of the simple safety OTP module 310 is searched and , the 'consent application amount included in the payment consent application information received in step 410' is compared with the reference amount.

As a result of the comparison in step 420, if the 'consent application amount included in the consent application information' is greater than (or equal to or greater than the reference amount retrieved from the reference amount storage unit 315), steps 430 to 475 are operated, otherwise Step 480 is activated.

In step 430, a master password input field and a confirmation box are output to the output unit.

In step 435, the user inputs the master password in the master password input field using the input unit of the user terminal 300 and selects a check box. In the case exemplified in step 235, the user memorizes '1234' as the master password, so he will input '1234' in the master password input field.

In step 440, the simple safe OTP calculation function and the decryption function are retrieved from the function storage unit 313, the 'encrypted OTP function unique code' is retrieved from the OTP function unique code storage unit 311, and the secret information DB 312 'User identification information and encrypted user organization password' are searched for, and the random value calculating unit 314 calculates a shared random value in a predetermined method, and the simple safety OTP module identifies the shared random value. In the case exemplified in steps 235, 245 and 9, '3702' is searched for as 'encrypted OTP function unique code', and 'user identification information and encrypted user organization password' are searched in the secret information DB 312, respectively. 'bani75' and '2345' will be searched. Also, if it is the case exemplified in step 340, the random value calculating unit 314 will calculate the current time value as a shared random value. For example, if the current time is 9:15, '915' will be calculated as a shared random value.

In step 445, the decryption function decrypts the searched 'encrypted OTP function unique code' and 'encrypted user organization password', respectively, using 'the input master password' as a decryption key. In the case exemplified in step 245, the decryption function will be 'encrypted variable - master password', which is the inverse function of 'variable to be encrypted + master password', which is the 'encryption function illustrated in step 245'. Also, in the case exemplified in step 440, '3702' and '2345' were searched as 'encrypted OTP function unique code' and 'encrypted user organization password', respectively, which are encrypted variables, and if the case exemplified in step 435 '1234' was entered as the master password. Therefore, in the case exemplified successively in steps 245, 435, and 440, '3702-1234 = 2468' and '2345-1234 = 1111' as 'decrypted OTP function unique code' and 'decrypted user organization password', respectively this will be calculated

In step 450, the simple safety OTP calculation function calculates the OTP using the 'decrypted OTP function unique code', 'the decrypted user organization password' and 'the calculated shared random value'. In the case continuously illustrated in steps 440 and 445, the 'decrypted OTP function unique code' and 'decrypted user organization login password' are '2468' and '1111', respectively, and the shared random value is '915'. In the above case, if the simple safety OTP calculation function is 'OTP function unique code + user organization password + shared random value' as exemplified in step 350, '2468+1111+915 = 4494' will be calculated as OTP.

In step 455, the user terminal 300 transmits the 'searched user identification information' and 'the calculated OTP' to the user organization server 200 as a reply matched with the 'transaction information received in step 410'. If it is the case exemplified successively in steps 440 and 450, 'bani75 as user identification information' and '4494 as OTP' will be transmitted.

In step 460, when the user organization server 200 receives 'user identification information and OTP' as a reply matching the transaction information, the user DB 210 matches the user identification information with the 'OTP function unique code and user organization 'password' is searched. In the case exemplified in steps 270, 455 and 11, '2468' as 'OTP function unique code and user organization password' matched to 'bani75 as user identification information' in the user DB 210 illustrated in FIG. 11 , respectively. and '1111' will be searched. In the case of the embodiment in which the OTP function-specific code storage is omitted in step 270, the 'Serial Number of the HOTP terminal' and the 'Serial Number of the password card' and the 'payment One of the 'account number of the account', 'mobile phone number' and 'e-mail address' may be searched for as 'shared ID and unique code of the OTP function'.

In step 465, the simple safety OTP calculation function is retrieved from the function storage unit 220 of the user organization server 200, and the random value calculation unit 230 calculates a shared random value by a predetermined method to the user organization server 200. determines the shared random value. The random value calculation unit 230 is shared random in the same way as the random value calculation unit configured in the 'simple secure OTP module before issuance stored in the module storage unit 120 of the identity authentication server 100' calculates the shared random value. It has the feature of calculating a value, since the 'simple safety OTP module before issuance stored in the module storage unit 120 of the identity authentication server 100' is installed in the user terminal 300, the same as in the user terminal 300 In this way, a shared random value is calculated. Therefore, in the case illustrated in step 440, if the time difference between the time at which step 440 is operated and the time at which step 465 is operated is negligible, the random value calculator 230 sets a time value corresponding to the current time of 9:15 ' 915' will be calculated as a shared random value.

In step 470, 'the searched OTP function unique code and user organization password' and 'the calculated shared random value' are substituted into the simple safety OTP calculation function to calculate the OTP. If it is the case consecutively exemplified in steps 450, 460 and 465, '2468' and '1111' are searched respectively as 'OTP function unique code and user organization password', respectively, and '915' will be calculated as a shared random value. Since the simple safety OTP calculation function is 'OTP function unique code + user organization password + shared random value', '2468 + 1111 + 915 = 4494' will be calculated as OTP.

In step 475, the identity authentication unit 240 compares the 'OTP calculated in step 470' and the 'OTP received in step 460' to determine whether or not there is a match. In the case illustrated in steps 455 and 470, the identity authentication unit 240 will determine that '4494 as the calculated OTP' and '4494 as the received OTP' match. According to an additional aspect of the present invention, when it is determined that a match is made in step 475, the 'consent information' for the 'consent application information for payment sent in step 410 by the user organization server 200' is verified. It is determined that it is, and an operation is performed to process the payment.

In step 480, the user terminal 300 transmits the 'consent information' to the user organization server 200 as a reply matched with the 'application information for payment consent received in step 410'. According to an additional aspect of the present invention, when the user organization server 200 receives the 'consent information' in step 480, the user organization server 200 transmits 'consent application information for payment in step 410 . It is determined that the 'consent information' for ' has been verified and operates to process the payment.


On the other hand, according to another aspect of the present invention for the case of storing the user organization password by one-way encryption using a hash function such that the user organization server 200 cannot decrypt the user organization password, steps 460 to 475 are as follows: Steps 460-1 to 475-1 may be substituted.

When the user organization server 200 receives 'user identification information and OTP' as a reply matched with the transaction information in step 460-1, the user DB 210 performs an 'OTP function unique code matched with the user identification information and Encrypted user organization password' is searched. In the case illustrated in steps 270, 455 and 11, '2468' as 'OTP function unique code and encrypted password' matched to 'bani75 as user identification information' in the user DB 210 illustrated in FIG. 11 , respectively and '1111 is an encrypted value' will be searched. In the case of the embodiment in which the OTP function-specific code storage is omitted in step 270, 'Serial Number of HOTP terminal' and 'Serial Number of password card' and 'payment One of the 'account number of the account', 'mobile phone number' and 'e-mail address' may be searched for as 'shared ID and unique code of the OTP function'.

In step 465-1, the 'inverse function of the simple safety OTP calculation function that calculates the user organization password' is searched for in the function storage unit 220 of the user organization server 200, and the random value calculation unit 230 uses a predetermined method. By calculating a shared random value, the user organization server 200 identifies the shared random value. If the simple safety OTP calculation function is as exemplified in step 350, the inverse function of the simple safety OTP calculation function for calculating the user organization password will be 'user organization password = OTP - OTP function unique code - shared random value'. The characteristics of the random value calculating unit 230 are the same as in step 465 .

In step 470-1, 'the received OTP', 'the searched OTP function unique code', and 'the calculated shared random value' are substituted into the inverse function of the simple safety OTP calculation function to inversely calculate the user organization password. If it is the case exemplified successively in step 455, step 460-1 and step 465-1, '4494' will be received as OTP, '2468' will be searched as OTP function unique code, and '915' will be a shared random value. will be calculated, and since the inverse function of the simple safety OTP calculation function is 'OTP - OTP function unique code - shared random value', '4494 - 2468 - 915 = 1111' will be calculated as the user organization password.

In step 475-1, the user authentication unit 240 determines whether the 'encrypted user organization password retrieved in step 460-1 matches' and the 'user organization password calculated in step 470-1'. In the case illustrated in steps 460-1 and 470-1, the identity authentication unit 240 encrypts the user organization password to store '1111 as the calculated user organization password' in the user DB 210. Calculate the encrypted value by substituting for ', and compare the '1111 encrypted value' with the '1111 encrypted value' found in step 460 to find out that they match, and determine that they match each other will be. An additional aspect in step 475 is the same as in step 375-1.

In the detailed description of the present specification so far, specific examples have been described, but these are used only for the purpose of describing the present invention and are not used to limit the meaning or scope of the present specification described in the claims. Therefore, the scope of the present specification should not be limited to the above-described embodiment, but should be defined by the following claims and their equivalents.

100: self-authentication server
110: module issuance DB
120: hair storage unit
200: user organization server
210: user DB
220: function storage unit
230: random value calculator
240: identity authentication unit
300: user terminal
310: simple safety OTP cap
311: OTP function unique code storage unit
312: secret information DB
313: function storage unit
314: random value calculator
315: reference solution storage unit

Claims (8)

delete delete delete delete The "user organization server" characterized in that "it is a computing device that can be connected to one or more of the identity authentication server and user terminal through a wired/wireless network and has an input unit, an output unit, a storage device, an arithmetic unit, and an OS" Receiving 'user identification information and OTP' that can be matched (A);
(B) the user organization server searching for 'OTP function unique code and user organization password' matched with the user identification information in the user DB;
(C) calculating, by the user organization server, a shared random value in the same way as the random value calculation unit configured in the simple secure OTP module before issuance stored in the identity authentication server calculates a random value;
The user organization server is the same as the 'pre-issued secure OTP module stored in the personal authentication server, a predetermined function stored to calculate OTP', and 'OTP function unique code, user organization password, and shared random value' as independent variables calculating OTP by substituting the 'OTP function unique code, user organization password, and shared random value' into the "simple safety OTP calculation function", which is characterized by calculating the OTP using (D);
(E) determining, by the user organization server, whether the calculated OTP is matched with the received OTP; Non-face-to-face authentication method using shared ID and simple safety OTP, characterized in that it includes a.
The "user organization server" characterized in that "it is a computing device that can be connected to one or more of the identity authentication server and user terminal through a wired/wireless network and has an input unit, an output unit, a storage device, an arithmetic unit, and an OS" Receiving 'user identification information and OTP' that can be matched (A);
retrieving, by the user organization server, 'OTP function unique code and encrypted user organization password' matching the user identification information in the user DB (B');
(C) calculating, by the user organization server, a shared random value in the same way as the random value calculation unit configured in the simple secure OTP module before issuance stored in the identity authentication server calculates a random value;
The user organization server is the same as the 'pre-issued secure OTP module stored in the personal authentication server, a predetermined function stored to calculate OTP', and 'OTP function unique code, user organization password, and shared random value' as independent variables Inverse calculation of the user organization password by substituting the 'OTP and OTP function unique code and shared random value' into the inverse function of the "simple safety OTP calculation function", characterized in that the OTP is calculated using (D');
determining whether the user organization server matches the inversely calculated user organization password and the searched encrypted user organization password (E'); Non-face-to-face authentication method using shared ID and simple safety OTP, characterized in that it includes a.
7. In claim 5 or 6,
The 'OTP function unique code retrieved from the user DB' is 'The serial number of the OTP terminal, the serial number of the password card, the account number of the payment account, the mobile phone number, and the e-mail address matched with the user identification information in the user DB. Non-face-to-face self-authentication method using shared ID and simple safety OTP, characterized in that it is a value calculated using one of '.
In claim 6,
The step (E ') is,
calculating an encrypted value by substituting the 'user organization password calculated in step (D') into the 'function for encrypting the user organization password to store it in the user DB'; and
Non-face-to-face self-authentication using shared ID and simple safe OTP, comprising the step of comparing the 'encrypted user organization password' with the 'encrypted user organization password retrieved in step (B')' Way.

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