Patent application number | Description | Published |
20090041231 | METHOD AND APPARATUS FOR PARTIALLY ENCRYPTING SPEECH PACKETS - Provided are a method and apparatus for partially encrypting speech packets, more specifically, a method and apparatus for selecting partial encryption sets used for a partial encryption technique in which compressed speech packets are partially encrypted to obtain the same effect as a full encryption technique. The method includes the steps of: (a) compressing respective speech files stored in a large-capacity speech database into the speech packets using a speech codec; (b) measuring single-bit loss distortion and sequential-bit loss distortion of the speech packets compressed in step (a); (c) generating standards for selecting partial encryption sets based on the measurement results of the single-bit loss distortion and sequential-bit loss distortion; (d) selecting the partial encryption sets according to the generated standards; and (e) encrypting the speech packets using the selected partial encryption sets. In this method, distortion sensitivity caused by loss of a speech packet can be exactly measured in various embodiments so that partial encryption sets can be efficiently and securely selected based on the measurement result. As a result, by reducing the amount of encryption operation, encryption services can be applied in various wireless communication environments. | 02-12-2009 |
20090113220 | ENCRYPTED BACKUP DATA STORAGE DEVICE AND STORAGE SYSTEM USING THE SAME - An encrypted backup data storage device and a storage system using the same are provided. A backup memory stores at least one of plain-text data and a secret key. A leakage current blocking circuit includes at least one inverter and a complementary metal oxide semiconductor (CMOS) NAND gate circuit and cuts off leakage current paths formed by the lines connected to the battery backup memory. | 04-30-2009 |
20100084682 | OHMIC ELECTRODE AND METHOD THEREOF, SEMICONDUCTOR LIGHT EMITTING ELEMENT HAVING THIS - There are provided an ohmic electrode, which includes a contact layer made of an Al alloy and formed on a nitride-based semiconductor layer functioning as a light emitting layer, a reflective layer made of Ag metal, formed on the contact layer and having some particles in-diffused to the semiconductor layer, and a protective layer formed on the reflective layer to restrain out-diffusion of the reflective layer; a method of forming the ohmic electrode; and a semiconductor light emitting element having the ohmic electrode. The present invention has strong adhesive strength and low contact resistance since the reflective layer and the light emitting layer directly form an ohmic contact due to the interface reaction during heat treatment, and the present invention has high light reflectance and excellent thermal stability since the contact layer and the protective layer restrain out-diffusion of the reflective layer during heat treatment. | 04-08-2010 |
20130156181 | APPARATUS AND METHOD FOR GENERATING SECRET KEY USING CHANGE IN WIRELESS CHANNEL ON WIRELESS COMMUNICATION NETWORK - A secret key generation apparatus and method are provided. The secret key generation apparatus includes at least one antenna, amplification/phase controllers, a transceiver, and a random sign& controller. The antenna receives a wireless signal from a counterpart terminal that performs wireless communication. The amplification/phase controllers control the amplification gain and phase of the wireless signal that is received via at least one antenna. The transceiver measures the status of a wireless channel using the wireless signal having the controlled amplification gain and phase, determines parameters based on results of the measurement, and generates a secret key based on results of the determination. The random signal controller controls the amplification/phase controllers so that the amplification gain and phase are adjusted whenever the transceiver generates a secret key. | 06-20-2013 |
20130163752 | APPARATUS AND METHOD FOR GENERATING GROUP KEY USING STATUS OF WIRELESS CHANNEL - An apparatus and method for generating a group key using the status of a wireless channel are provided. The apparatus includes a representative channel response selection unit for selecting a representative channel response signal from among pilot signals received from slave terminals. A key generation unit generates a group key based on a representative channel response value of the representative channel response signal. A hash value generation unit generates a hash value corresponding to the group key. A transmission pilot control unit adjusts power intensities of transmission pilots of the respective slave terminals using the channel response value of the representative channel response signal and channel response values and transmission power intensities of the slave terminals. A communication unit is individually connected to the slave terminals and configured to transmit pilot signals, power intensities of which have been adjusted, and the hash value to the slave terminals. | 06-27-2013 |
20140068780 | APPARATUS AND METHOD FOR REMOTELY DELETING CRITICAL INFORMATION - An apparatus and method for remotely deleting critical information is provided. The apparatus includes a storage unit, an identity determination unit, and a broadcast unit. The storage unit stores an input value and an output value for the input value with respect to a physically unclonable function (PUF) of each of a plurality of mobile terminals. The identity determination unit determines the identity of a corresponding mobile terminal based on received information about the loss of the mobile terminal. The broadcast unit extracts the input and output values of the PUF of the corresponding mobile terminal from the storage unit based on information transferred from the identity determination unit, and broadcasts the extracted input and output values to all the mobile terminals. | 03-06-2014 |
20140153725 | LOW-POWER ENCRYPTION APPARATUS AND METHOD - A low-power encryption apparatus and method are provided. The low-power encryption apparatus includes a mask value generation unit, a mask value application unit, a round key application unit, a mask operation unit, a shift operation unit, and a shift operation correction unit. The mask value generation unit generates a mask value M having the same bit length as input round function values. The mask value application unit generates first masking round function values by applying the mask value M. The round key application unit generates second masking round function values by applying round key values. The mask operation unit generates third masking round function values by performing a mask addition operation. The shill operation unit generates fourth masking round function values by performing a circular shift operation. The shift operation correction unit generates output round function values by performing an operation using the mask value M. | 06-05-2014 |