Abstract: Disclosed is an apparatus for code obfuscation includes: an input unit that receives execution codes for android applications; a code analyzer that separates the input execution codes into sensitive codes that needs to be protected from application forgery attack and general codes except for the sensitive codes by analyzing the input execution codes; a dalvik to C code converter that creates native codes by converting the sensitive codes into a C code; an obfuscator that obfuscates the native codes and the general codes; a self code protector that encrypts the obfuscated native codes by adding a tamper-detection code to the obfuscated native codes and then creates self-modified native codes by adding a loading routine; and a code combiner that combines the self-modified native codes with the obfuscated general codes.

Abstract: Disclosed is an apparatus for code obfuscation includes: an input unit that receives execution codes for android applications; a code analyzer that separates the input execution codes into sensitive codes that needs to be protected from application forgery attack and general codes except for the sensitive codes by analyzing the input execution codes; a dalvik to C code converter that creates native codes by converting the sensitive codes into a C code; an obfuscator that obfuscates the native codes and the general codes; a self code protector that encrypts the obfuscated native codes by adding a tamper-detection code to the obfuscated native codes and then creates self-modified native codes by adding a loading routine; and a code combiner that combines the self-modified native codes with the obfuscated general codes.

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 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 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 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: A distributed Rivest Shamir Adleman (RSA) signature generation method in an ad-hoc network and a node of an ad-hoc network. The distributed RSA signature generation method in an ad-hoc network includes distributing key share information, which is generated using a maximum distance separable (MDS) code and a random symmetric matrix, to a plurality of nodes; generating, in a fewer number of nodes than the plurality of nodes, a partial signature using the distributed key share information; transmitting the partial signature to a signature generation node; and generating an RSA signature using the partial signature, in the signature generation node.

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: A mobile system, a service system, and a service providing method for securely transmitting private information for use in a service are provided. The mobile system maintains at least one user data and identification data with respect to the user data used for processing at least one service, sets a session key for the service system, and encrypts service data identified based on the identification data to transmit to the service system.

Abstract: A key generation method for self-configuration is provided which includes selecting existing nodes as many as a predefined reference number t from nodes which configure a network; transmitting a partial key request message to the selected existing nodes; and generating a node key based on randomized partial keys received in response to the partial key request. Accordingly, when a new node intends to join the network, the existing nodes forming the network can allocate a node key to the new node by themselves. Also, whether the node key of the new node is compromised or not can be verified using the error-checking witness.

Abstract: A mobile system, a service system, and a key authentication method to manage a key in a local wireless communication are provided. The mobile system and the service system may generate a hash value with respect to a public key of the service system using an identical hash function, and output a result corresponding to the hash value.

Abstract: A method of protecting a broadcast frame, the method comprising broadcasting a beacon and a maintenance beacon frame (MBF) from an access point (AP) to a plurality of terminals during a maintenance beacon waiting period (MBWP); and broadcasting broadcast management frames (BMFs) from the AP to the plurality of terminals during a broadcast management frame waiting period (BMFWP), wherein the MBF comprises a BMFs message integrity code (MIC) field including a BMFs MIC calculated from concatenated BMFs to be sent in a current beacon interval.

Abstract: A method and system for performing a distributed verification with respect to measurement data in a sensor network. The method of performing the distributed verification with respect to measurement data in a sensor network includes: verifying, by an aggregator, the measurement data received from each of a plurality of sensors; generating, by the aggregator, verification request data by using the verified measurement data; transmitting the verification request data to a verifier; and verifying, by the verifier, the aggregator via a predetermined number of sensors of the plurality of sensors and the verification request data. The method of performing a distributed verification with respect to measurement data in a sensor network further includes transmitting, by the aggregator, an aggregation result with respect to the measurement data to a base station when the aggregator is verified; and verifying, by the base station, the aggregation result.

Abstract: A batch verification apparatus and method wherein, the method includes: generating a plurality of secret keys, a plurality of public keys corresponding to the plurality of secret keys, and a plurality of verification values corresponding to the plurality of public keys; calculating a first batch verification value based on the plurality of verification values; calculating a second batch verification value based on the plurality of secret keys and the plurality of verification values; comparing the first batch verification value and the second batch verification value; and determining that a batch of the received plurality of verification values is verified when the first batch verification value is equal to the second batch verification value.

Abstract: A key calculation method and a shared key generation method, the key calculation method including: generating two keys to perform a key calculation; calculating a first value based on coefficients having an identical coefficient value among coefficients included in each of the two keys; and performing a coordinates operation or an exponentiation operation based on the first value, wherein the calculating of the first value is performed with respect to each of coefficient values included in the two keys, excluding 0.

Abstract: A tag authentication method, and a tag and reader performing the method are provided. The tag authentication method, including: a reader generating a first random number and transmitting the first random number to a tag; the reader receiving a second random number and a first verification value from the tag; the reader computing a second verification value based on the first random number and the second random number; and the reader comparing the first verification value and the second verification value.

Abstract: A distributed Rivest Shamir Adleman (RSA) signature generation method in an ad-hoc network and a signature generation node are provided, including steps for distributing key information to a plurality of nodes using an RSA parameter and a maximum distance separable (MDS) code, in a dealer node, generating a partial signature using the key information and transmitting the generated partial signature to a signature generation node, in the plurality of nodes, and generating an RSA signature using the partial signature, in the signature generation node, wherein the RSA signature is generated using the partial signature, received from a fewer number of nodes than the entire plurality of nodes.

Abstract: A method for generating, operating, and using a sparse w-NAF key for encryption is disclosed. The method for generating a key comprises generating a string of a number of coefficients, in which at most one coefficient, excluding 0, among a consecutive w number of coefficients, corresponds to a positive odd integer equal to or less than 2w (w being a natural number equal to or more than 2); and outputting the generated string as a key. Accordingly, an encryption is executed through an exponential operation or scalar multiplication using a sparse w-NAF key having the scarce coefficients, excluding 0, such that an encryption pace is improved.

Abstract: A public key generation method in Elliptic Curve Cryptography (ECC), and a public key generation system performing the method are provided. The public key generation method includes reducing a sequence length of the signed ternary ?-adic representation of the private key ‘k’ using properties of an elliptic curve, representing a reduced secret key ‘k’ in a signed ternary ?-adic representation; and computing a public key kP by multiplying the ?-adic representation of the private key ‘k’ whose sequence length is reduced on point P on the elliptic curve.

Abstract: A mobile system, a service system, and a service providing method for securely transmitting private information for use in a service are provided. The mobile system maintains at least one user data and identification data with respect to the user data used for processing at least one service, sets a session key for the service system, and encrypts service data identified based on the identification data to transmit to the service system.