Abstract: Disclosure relates to a method of sharing a session key between wireless communication terminals using a variable-length authentication code. The method includes: generating a public key by using an own private key; generating a message including the public key and a first random number and encoding the message using an own secret key to exchange an encrypted message with the other terminal; decoding the encrypted message of the other terminal by receiving a secret key of the other terminal; generating an authentication code by calculating the first random number and a second random number included in the decoded message; obtaining a medium value from the authenticated code; and generating a session key by using a public key included in the decoded message of the other terminal.

Abstract: Provided are method and apparatus for authenticating a password of a user terminal. The method includes: pre-setting, by a user, a password and an identification image for identifying the password; moving a keypad window or an image window realized on a screen of the user terminal according to an action of the user; determining, when a plurality of images included in the image window and a plurality of keys included in the keypad window sequentially overlap with each other, whether a plurality of keys and the identification image corresponding to the password sequentially overlap; and authenticating the password when the plurality of keys and the identification image corresponding to the password sequentially overlap. Accordingly, password information may be protected from a third person observation as the user inputs a pre-set password in an indirect method without having to directly input the pre-set password through an authentication interface.

Abstract: Provided are method and apparatus for authenticating a password of a user terminal by using a password icon. The method includes: method of authenticating a password of a user terminal, the method including: pre-setting, by a user, a password icon corresponding to a password and a moving direction of the password icon; sequentially moving the icon according to actions of the user at a screen of the user terminal; when the icon is sequentially moved, determining whether the pre-set password icon and the pre-set moving direction of the password icon are matched; and authenticating the password when the password icon and the moving direction of the password icon is sequentially matched.

Abstract: Provided is a method and apparatus for authenticating a password, wherein the method includes: generating at least one input grid cell into which a password is input from among a plurality of grid cells realized on a screen of a user terminal; and authenticating the password when the password is identical to a number of identification grid cells included in an authentication range predetermined based on the at least one input grid cell, wherein the identification grid cells are set to authenticate the password from among the plurality of grid cells. Accordingly, password information may be prevented from being exposed to a third person observer since a variable password is input whenever a user tries password authentication in a terminal.

Abstract: Disclosure relates to a method of sharing a session key between wireless communication terminals using a variable-length authentication code. The method includes: generating a public key by using an own private key; generating a message including the public key and a first random number and encoding the message using an own secret key to exchange an encrypted message with the other terminal; decoding the encrypted message of the other terminal by receiving a secret key of the other terminal; generating an authentication code by calculating the first random number and a second random number included in the decoded message; obtaining a medium value from the authenticated code; and generating a session key by using a public key included in the decoded message of the other terminal.