Abstract:
A method of authenticating a user of a terminal operating a server and connected to the terminal through a communication network, in which a password needed for authentication is inputted as icons, rather than numerals or characters, thereby preventing leakage or theft of the password. Through the present invention, security is improved in processing a password in an information processing device or a communication network, and furthermore, leakage of the password is fundamentally prevented in the process of inputting the password by a user. Therefore, an effect of securing reliability of the overall authentication process may be obtained.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a method of authenticating a user of a terminal operating a server and connected to the server through a communication network, in which a password needed for authentication is inputted as icons, rather than numerals or characters, thereby preventing leakage or theft of the password. 
     2. Background of the Related Art 
     Along with the advancements of electronic communication networks such as the Internet and mobile communications, electronic transactions are performed in a variety of areas including commercial businesses, banking, administrative affairs, communications and the like. Accordingly, a variety of authentication techniques have been developed and used for security of transactions. 
     In authentication techniques for electronic transactions performed through the electronic communication networks, a password may be regarded as the most common and essential element. The password may be practically a unique authentication means in an electronic transaction where face-to-face meeting between an authentication subject and an authentication object is excluded. 
     A password for an electronic transaction is generally configured as a numeric string, a character string, or a mixture of these strings. A user inputs the password by manipulating a keyboard or keypad of a terminal such as a computer, a mobile communication device, an automatic teller machine (ATM) or the like. 
     A password may be leaked through keyboard hacking or wiretapping in the process of inputting and transmitting the password by manipulating a keyboard or a keypad, and thus methods have been developed which can implement an input screen in the form of a keyboard or a keypad on a display of a terminal and input a password using a mouse or a touch screen. 
     However, the authentication method described above commonly uses a password based on numerals or characters, and has two problems in that the process of inputting a password is exposed to third parties in the neighborhood, and the password is inevitably leaked by a hacking program when the screen is transmitted. 
     SUMMARY OF THE INVENTION 
     Accordingly, the present invention has been made in view of the above problems, and it is an object of the present invention to provide a method of authenticating a user of a terminal using an icon password, in which security is improved in processing a password in an information processing device or a communication network. Leakage of the password is fundamentally prevented in the process of inputting the password by a user, thereby securing reliability on the overall authentication process. 
     To accomplish the above object, according to an aspect of the invention, there is provided a method of authenticating a user of a terminal using an icon password, the terminal being connected to a server through an electronic communication network, wherein an icon database and an authentication database are connected to the server, the icon database storing a plurality of icons assigned with unique values and the authentication database storing authentication information including passwords of respective users. The method comprises: an authentication requesting step, allowing the terminal to request authentication to the server through the communication network; an icon retrieve step, allowing the server to retrieve unique values and icons corresponding to the unique values from the icon database; an assigned value creation step, allowing the server to create the same number of assigned values as the retrieved unique values for each icon through a non-duplicate random number generation; an icon transmission step, allowing the server to transmit icon information containing the assigned values to the terminal through the communication network; an input waiting step, allowing the terminal to implement a password input screen based on the transmitted icon information; an input step, allowing the terminal to transmit authentication information containing assigned values of the selected icons to the server through the communication network; a conversion step, allowing the server to convert the assigned values contained in the transmitted authentication information to corresponding unique values; an inquiry step, allowing the server to query the authentication database using authentication information converted from the assigned values; and an authentication step, allowing the server to accept the authentication request if the authentication information is valid. 
     In the method of authenticating a user, the icon database stores a plurality of icons assigned with the same unique value, and the server randomly extracts a unique value and an icon from a plurality of icons of the unique value in the icon database in the icon retrieve step. In the method of authenticating a user, in which the icon database stores a plurality of icons assigned with feature values, and the authentication database stores the authentication information including passwords and feature value lists of respective users, the icon retrieve step comprises: a list inquiry step allowing the server to retrieve the feature value list from the authentication database; an icon extraction step of allowing the server to randomly extract an icon having a unique value as a feature value from the icon database; and an icon selection step of re-performing the icon extraction step when the extracted icon is a multi-icon having a plurality of feature values, and a plurality of duplicated values among feature values of the extracted icon are contained in the feature value list, or when the extracted icon is a multi-icon, the duplicated value is singular, and the duplicated value does not coincide with the unique value, wherein the icon extraction step and the icon selection step are repeatedly performed for each unique value. 
     According to the present invention, security is improved in processing a password in an information processing device or a communication network. 
     Furthermore, leakage of the password is fundamentally prevented in the process of inputting the password by a user. Therefore, an effect of securing reliability on the overall authentication process may be obtained. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a system configuration for performing the present invention. 
         FIG. 2  is a view showing an example of an input screen of the present invention. 
         FIG. 3  is a view showing an example of information stored in an icon database of the present invention. 
         FIG. 4  is a view showing a process of implementing an input screen by applying assigned values of the present invention. 
         FIG. 5  is a flowchart illustrating the present invention. 
         FIG. 6  is a flowchart illustrating the steps of processing a computer program of the present invention. 
         FIG. 7  is a view showing an example of information stored in an icon database according to a modified embodiment of the present invention. 
         FIG. 8  is a view showing an example of information stored in the icon database of the present invention, assigned with feature values. 
         FIG. 9  is a view showing the multi-icon of  FIG. 8 . 
         FIG. 10  is a flowchart illustrating the steps of retrieving icons in an embodiment of the present invention to which multi-icons are applied. 
         FIG. 11  is a view showing a process of selecting icons of the present invention. 
         FIG. 12  is a view showing an example of an input screen using multi-icons of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The detailed configuration of the invention will be hereafter described with reference to the accompanying drawings. 
     First,  FIG. 1  shows constitutional components for performing the present invention, comprising a server  10  and terminals  20  connected through an electronic communication network, in addition to an icon database  11  and an authentication database  12  connected to the server  10 . 
     Here, as shown in  FIG. 1 , the communication network may include a public switched telephone network (PSTN), a public switched data network (PSDN), a value added network (VAN), a local area network (LAN), a wide area network (WAN), the Internet, a mobile communication network, and the like. The communication networks listed above may not be an individual concept that can be physically and clearly distinguished. Since the present invention relates to a technique of authenticating a user, not to the configuration of the electronic communication network itself, or a technique of distributing information itself, claims on the electronic communication network are not specifically limited. 
     In the present invention, a variety of electronic devices having an input and output means, such as a computer, a mobile communication device, an ATM, or the like, may be used as the terminal  20 . As specific examples, the terminal may be a computer connected to the Internet through a modem and the PSTN or through a wired or wireless LAN, a cellular phone connected to the mobile communication network as a mobile station, a private ATM connected to the VAN, an ATM connected to a financial wide area network, and the like as shown in  FIG. 1 . 
     On the other hand, the icon database  11  for storing information related to icons for performing the present invention and the authentication database  12  for storing authentication information such as passwords of users are connected to the server to which the terminal  20  is connected through the electronic communication networks. The databases do not need to be physically separated from the server  10  and may be constructed within a memory device of the server  10 . 
     That is, the databases of the present invention may be constructed in a variety of forms, such as being constructed in the memory device within the server  10  or constructed as a server  10  or storage located at a remote place. Connectivity between the server  10  and the databases shown in  FIG. 1  is not limited to physical connectivity, but it means a logical connection between a server program performing authentication and the databases. 
     In addition, information stored in the databases may be encrypted to prevent hacking the server  10  or the databases or stealing by an operator. Since the encryption may be selectively performed by those skilled in the art, claims on the encryption are not specifically limited. 
     The present invention is fundamentally to shift away from a conventional numeral or character based password system. A password is configured not with a numeric string or a character string, but with a permutation or a combination of icons having identity. A password is inputted in a method of selecting icons configured on the screen of the terminal  20  as shown in  FIG. 2 . 
     That is, a user memorizes a password not as a numerical series such as “1, 2, 3, and 4”, but as a permutation of icons such as “car, flower, plane, and book”. On the other hand, a unique value is assigned to each of the icons as shown in  FIG. 3  to process the icons electronically. Although integers and symbols the same as those of a telephone keypad are assigned to twelve icons in the embodiment shown in  FIG. 3 , various kinds of data other than the integers, such as characters, combinations of characters and numerals, or the like, may be assigned as unique values. 
     Here, the unique values are data assigned to respective icons to identify an icon in electronic data processing. Since a user recognizes only icons configuring a password and does not recognize unique values assigned to respective icons, the same number of assigned values as the unique values are created and transmitted to the terminal  20  in place of the unique values when icon information is transmitted to the terminal  20 , and thus leakage of the unique values may be fundamentally prevented. 
     That is, the same number of non-duplicate random numbers as the unique values are created and assigned to respective icons as shown in  FIG. 4 , and icon information including the assigned values and the icons is transmitted to the terminal  20 . Therefore, the unique values stored in the icon database  11  may be prevented from being leaked outside. Although transmission information can be stolen by wiretapping the electronic communication network, or input and output information can be stolen by a hacking program in the terminal  20 , security of the password may be guaranteed since the original unique values of the icons may not be exposed. 
     In the embodiment shown in  FIG. 4 , integers from 0 to 9 are assigned as unique values, and each of the unique values specifies the location of a corresponding icon on the input screen. The assigned values are configured with the same number of integers from 0 to 9 as the unique values in the form of a changed order, through non-duplicate random number generation for generating integers in the range the same as that of the unique values. 
     The icon information comprising the assigned values created as such and icons is transmitted from the server  10  to the terminal  20 , and the terminal receiving the icon information implements an input screen. In the embodiment shown in  FIG. 4 , the assigned values specify locations of icons on the input screen. As a result, a user inputs a password through the input screen configured in the form that is randomly changed each time. 
     Since the values assigned to respective icons as described above are non-duplicate random numbers that are the same as the unique values in the number, the assigned values correspond one-to-one to the unique values. Therefore, if a user input a password in a method of selecting icons and authentication information including the assigned values assigned to the selected icons are transmitted to the server  10 , the server  10  converts the assigned values included in the authentication information to unique values based on the previously set correspondence relation, and accepts or rejects authentication by determining validity of the unique values. 
       FIG. 5  is a flowchart illustrating the present invention to which the icons, unique values, and assigned values are applied, which will be described below in detail. 
     First, the terminal  20  starts an authentication process of the present invention from the authentication request step S 10  for requesting authentication to the server  10  through a communication network. As the authentication request is received, the server  10  performs the icon retrieve step S 20  for retrieving unique values and icons respectively corresponding to the unique values from the icon database  11 . 
     The icon database  11  stores unique values and icons corresponding to the unique values. An icon may simply correspond to a unique value as shown in  FIG. 3 , or a plurality of icons may correspond to a unique value as shown in  FIG. 7 . In this case, icons assigned with the same unique value are configured to be recognized as icons having the same feature by users and distinguished from other icons. 
     As described, when the icon database  11  stores a plurality of icons assigned with the same unique value, the server  10  performs the icon retrieve step S 20  by randomly extracting a unique value and an icon among a plurality of icons assigned to the unique value from the icon database  11 . Accordingly, an input screen configured with icons of a variety of combinations may be implemented, and thus security may be ensured. 
     After completing the icon retrieve step S 20 , the server  10  performs the assigned value creation step S 30  for creating the same number of assigned values as the retrieved unique values for each icon through non-duplicate random number generation and the icon transmission step S 40  for transmitting icon information containing the assigned values to the terminal  20  through the communication network. 
     The icon information may contain information related to icons such as image data of the icons and the like, in addition to the assigned values, which are essential elements. The configuration of such icon information may be changed depending on communication loads or characteristics of the electronic communication network. If the image data of icons are not contained in the icon information, an input screen may be implemented in a method of storing image data of icons in a storage device of the terminal  20  and transmitting icon information containing information for identifying images of icons. 
     The terminal  20  receiving the icon information performs the input waiting step S 51  for implementing a password input screen based on the transmitted icon information. Then, if a user selects icons corresponding to a password, the terminal  20  performs the input step S 52  for transmitting authentication information containing assigned values of the selected icons to the server  10  through the communication network. The user inputs the password by selecting icons using a mouse, a touch screen, or the like. 
     When the server  10  receives the authentication information containing identification of the user, the icon password, i.e., the assigned values, and the like, the server  10  performs the conversion step S 61  for converting the assigned values contained in the authentication information to corresponding unique values. Then, the server  10  authenticates the user through the inquiry step S 62  for querying the authentication database  12  using the authentication information converted from the assigned values, and the authentication step S 63  for accepting the authentication request if the authentication information is valid. 
       FIG. 6  is a flowchart illustrating the steps of processing a computer program to perform the present invention. In the embodiment of the figure, array variables of “ICON”, “ORIG”, and “DIST” respectively having n elements are declared, and the variables are respectively used for icons, unique values, and assigned values. Although the icons, unique values, and assigned values are expressed as array variables in the embodiment, which means that certain memory capacities are allocated for electronic data processing, they are not limited to variables of mathematical meanings, but may have different constellations such as image data, numerals, characters, or the like. 
     The flowchart shown in  FIG. 6  is configured in three parts of left, middle, and right based on the process of transmitting and receiving a password through the electronic communication network. The three parts show the processes sequentially performed by the server  10 , the terminal  20 , and the server  10 . In the steps of the middle part performed by the terminal  20  and the steps of the right part performed by the server  10 , “EVENT” and “PW” are declared as array variables having m elements, and these variables respectively correspond to the icons selected by a user and a password of the user stored in the authentication database  12 . 
     On other hand, since icons constructing a password in the present invention are featured in that an icon may be recognized as a plurality of meanings unlike a numeral or a character, security in the authentication process may be enhanced through such a multi-icon. If a feature value is assigned to icons depending on internal meaning of the icons as shown in  FIG. 8 , multi-icons having a plurality of feature values may be derived as shown in  FIG. 9 . If such feature values are stored in the icon database  11  together with icons and used in implementing a password input screen, input intention of a user may not revealed although all the icons selected in the process of inputting a password are exposed. 
     That is, icons themselves are not used as a password, but meanings of the icons assigned with feature values are used as a password. In the embodiment to which the icons of  FIG. 8  are applied, a user does not memorize a password as a permutation of icons, but as a permutation of features such as “animal, plant, human, and food”. 
     However, since the user may be confused due to multi-icons in the process of selecting icons, needed icons are retrieved and an input screen is implemented through the process shown in  FIGS. 10 and 11  to allow the user to correctly input a password. 
     Since icons for constructing a password input screen should be selected depending on a password of the user when the multi-icons are applied as described, a process of querying a feature value list constructing a password should be preceded before the needed icons are extracted from the icon database  11 . Here, the feature value list is a combination of feature values configuring a password. If a password is a permutation of feature values, the feature value list is a combination of corresponding feature values. Since a permutation of feature values corresponding to a feature value list has a plurality of numbers of cases, it is advantageous for security to retrieve the feature value list instead of directly retrieving a password in the icon retrieve step S 20 , i.e., in the initial stage. 
       FIG. 11  shows an example of selecting icons to be used for a password input screen when a user memorizes a password as “weather, animal, sea, and sky” in an embodiment to which the icon database  11  formed as shown in  FIG. 8  is applied, i.e., when a password expressed in feature values is “4, 0, 7, and 6”. The selection of icons will be described below based on the steps shown in the flowchart of  FIG. 10 . 
     First, the server  10  performs the list inquiry step S 21  for retrieving a feature value list of a corresponding user from the authentication database  12  and the icon extraction step S 22  for randomly extracting an icon having a certain unique value as a feature value from the icon database  11 . 
     At this point, if the icon extracted in the icon extraction step S 22  is a multi-icon having a plurality of feature values, and a plurality of duplicated values among the feature values of the extracted icon are contained in the feature value list, or if the extracted icon is a multi-icon, the duplicated value is singular, and the duplicated value does not coincide with the unique value, the icon selection step S 23  of re-performing the icon extraction step S 22  is performed. 
     Here, the icon extraction step S 22  and the icon selection step S 23  are repeatedly performed for each unique value, and finally, the same number icons as the unique values are determined. 
       FIG. 12  shows an example of an input screen implemented by the embodiment shown in  FIG. 11 . If a user selects icons meaning “weather, animal, sea, and sky”, which are the user&#39;s password, unique values of “4, 0, 7, and 6” corresponding to the selected icons are transmitted as a password. In this case, since two of the selected icons are multi-icons, the number of cases of the password becomes 3 as shown in the figure. 
     As described above, through the icon password system of the present invention in which numerals and characters are excluded, further superior security may be achieved compared with a conventional numeral and character based password, and a further improved security effect may be obtained if the assigned values and multi-icons described above are used together. 
     While the present invention has been described with reference to the particular illustrative embodiments, it is not to be restricted by the embodiments but only by the appended claims. It is to be appreciated that those skilled in the art can change or modify the embodiments without departing from the scope and spirit of the present invention.