Samsung Electronics Co., Ltd.

Weon-il Jin

Dae-youb Kim

Hwan-joon Kim

Maeng-hee Sung

Sung-joon Park

Mi-suk Huh

Jung-Hee Cheon

Myung-hwan Kim

Eun-sun Yoo

Dong-Hoon Lee

Bae-eun Jung

Bum-Jin Im

Kyung-Hee Lee

Nam-Su Jho

Won-Keun Kong

Hee-jean Kim

Kyung-hee Lee

Jung-yeon Hwang

Chang-woo Seo

Nam-su Jho

Su-Myeon Kim

Sung-ioon Park

Hwan-ioon Kim

A tag generation method for generating tags used in data packets in a broadcast encryption system is provided. The method includes detecting at least one revoked leaf node; setting a node identification (node ID) assigned to at least one node among nodes assigned node IDs at a layer 0 and to which the at least one revoked leaf node is subordinate, to a node path identification (NPID) of the at least one revoked leaf node at the layer 0; generating a tag list in the layer 0 by combining the NPID of each of the at least one revoked leaf nodes at the layer 0 in order of increment of node IDs of the corresponding at least one revoked leaf nodes; and generating a tag list in a lowest layer by repeatedly performing the setting and generation operation down to the lowest layer.

Tag generation method in broadcast encryption system

A context aware apparatus is provided. The context aware apparatus includes an extracting unit configured to extract a terminological-box (T-box) from a semantic model, a first generating unit configured to generate a reasoning rule based on the extracted T-box, a second generating unit configured to generate a first assertion-box (A-box) based on sensing information, and a reasoning unit configured to infer a user context based on the reasoning rule and the first A-box.

Context aware apparatus and method

An assertion management method includes collecting a SameAs assertion from a plurality of assertions; searching the plurality of assertions for any assertion having a first individual of the SameAs assertion as an instance; and creating a new assertion having a second individual of the SameAs assertion as an instance from each found assertion.

Assertion management method and apparatus, and reasoning apparatus including the assertion management apparatus

A combination-based broadcast encryption method includes: assigning by a server a base group of different combinations to each user; producing and sending secret information for each user by using as a base the base group allocated to each user; producing and sending an inverse-base parameter value through calculations with integers used to produce the base group and key value information of one or more privileged users; and deriving a group key by using the key value information of the privileged users, encrypting a session key by using the derived group key, and sending the encrypted session key to each user. Accordingly, each user is assigned a different base through a combination, thereby having security against collusion attacks.

Combination-based broadcast encryption method

A user key management method for a broadcast encryption includes assigning node path identifiers (IDs) to nodes arranged in sequence; assigning random seed value keys to the nodes according to the node path IDs; generating key values by repeatedly applying a hash function to the assigned random seed value keys; and assigning the generated key values to the nodes in sequence. Accordingly, it is possible to reduce the transmission overhead that is most important matter in the broadcast encryption to less than the number of the revoked users. Further, there is an advantage that the transmission overhead of the exemplary embodiments of the present invention is remarkably reduced compared with the Subset Difference method.

Method of managing user key for broadcast encryption

An apparatus and method for generating a key for a broadcast encryption. The apparatus includes a node secret generator for managing a user that receives broadcast data in a tree structure and for generating a unique node secret for each node in the tree structure. The apparatus also includes an instant key generator for temporarily generating an instant key used at all nodes in common in the tree structure, and a node key generator for generating a node key for each node by operating the node secret generated at the node secret generator and the instant key generated at the instant key generator. Thus, key update can be efficiently achieved.

Apparatus and method for generating a key for broadcast encryption

A tag generation method for generating tags used in data packets in a broadcast encryption system is provided. The method includes detecting at least one revoked leaf node; setting a node identification (node ID) assigned to at least one node among nodes assigned node IDs at a layerand to which the at least one revoked leaf node is subordinate, to a node path identification (NPID) of the at least one revoked leaf node at the layer; generating a tag list in the layerby combining the NPID of each of the at least one revoked leaf nodes at the layerin order of increment of node IDs of the corresponding at least one revoked leaf nodes; and generating a tag list in a lowest layer by repeatedly performing the setting and generation operation down to the lowest layer.

A method for authorizing an off-line image device to play contents in use of a recording medium, including recording an encrypted key on a recording medium; recording contents on the recording medium using the encrypted key; and recording information as to a play right to play the contents recorded on the recording medium. Thus, the off-line image device can be authorized to play contents in use of the recording medium. As a result, the off-line image device can play contents that are recorded on the recording medium and must be authorized to play the contents.

Method for authorizing contents play rights in use of a recording medium

A user key allocation method for broadcast encryption is provided. The user key allocation method includes generating a plurality of subsets by dividing one group including a plurality of nodes to sub-groups and allocating key sets with respect to the subsets, respectively. The nodes included in the subset may be odd nodes and even nodes of the nodes of the group. The nodes are arranged so that privileged nodes are consecutive or there is only one privileged node. Accordingly, it is possible to reduce the data size transmitted from the server to the nodes by constituting one or more subsets from the nodes consecutively arranged and providing key sets with respect to the subsets.

User key allocation method for broadcast encryption

A user terminal apparatus with a security function and a security-control method are provided, which may prevent unauthorized use of the user terminal apparatus without requiring a user to lock up the user terminal apparatus. The user terminal apparatus includes an input sensing unit which senses a user's input to the user terminal apparatus, an information collecting unit which collects information regarding an input state, which is determined based on the user's input, and a transition of the determined state, and a security-control unit which determines whether the user is valid based on the collected information and controls a security function.

User terminal with security function and security-control method

A method of generating prevention and control data to verify validity of data to be transmitted, and an apparatus to perform the method, the method including generating the prevention and control data according to composing information of the data to be transmitted, and transmitting the prevention and control data along with the data to be transmitted to verify the validity of the data to be transmitted.

Apparatus and method of generating and detecting prevention and control data for verifying validity of data

A method and a system for managing a key of a home device in a broadcast encryption system are provided. A hierarchical structure of a group set comprising a plurality of nodes corresponding to the home server and a plurality of nodes corresponding to the home device is formed. A key set to be allotted to the node set is generated. The node group is allowed to correspond to the key set to generate key-node corresponding information according to a request of the home server.

Growing community of inventors

Suwon-si, South Korea

Weon-il Jin