Abstract: A system, method and program product for defending against man in the middle (MITM) attacks directed at a target server. A system is provided that includes an activity recording system that records an incoming IP address, userid, and time of each session occurring with the target server; an activity analysis system that identifies suspect IP addresses by determining if an unacceptable number of sessions are occurring from a single incoming IP address during a predefined time period; and a countermeasure system for taking action against suspect IP addresses.

Abstract: A method and apparatus for generating shared session keys. The method and apparatus does not rely on strong random number generation. The first node sends a timestamp and random sequence to the second node. The second node generates a message authentication code (MAC) using this data and a shared secret key. The MAC is then used to encrypt a reply containing a second timestamp and second random sequence from the second node. The first node receives this message and decrypts it by generating the same MAC. Both nodes then generate a session key using the shared set of timestamps and random sequences.

Abstract: Method for shared secret verification in secure data exchange, in which at least two parties, indicated as Alice and Bob, each have a secret and seek to determine whether they share the same secret or not without disclosing the secret itself to each other or any third party. Alice picks a random number RA, encrypts it using Bob's public key, adds the value of her secret, and sends the result K to Bob. Bob receives K, subtracts his secret, and decrypts that using his private key, generating L. Bob performs a one-way function on L and sends the result M to Alice. Alice takes her original RA, performs the same function and verifies whether the result equals the received M. Alice sends her original RA to Bob. Bob receives the RA and verifies whether it equals L, allowing Bob to determine if Alice shares the same secret.

Abstract: A method and system for secure communication is provided. The method for secure communication with devices includes: obtaining a parameter for protecting a content; authenticating each other by exchanging a certificate with the device; and exchanging a key with the device using a key authenticated through the certificate to establish a secure authenticated channel with the device. Accordingly, it is possible to establish the secure authenticated channel and perform secure communication by computing a secure authenticated channel key.

Abstract: An information handling system includes a memory and a processor to execute instructions stored in the memory, which causes the processor to at least: send identification information to a second information handling system in response to an identification request broadcast from the second information handling system via a short-range communication; receive first authentication information for a local application and a remote service from the second information handling system; receive a copy of the local application; authenticate a user for the copy of the local application and for the remote service prior to the user logging on to the information handling system; receive second authentication information from the user to access the information handling system; authenticate the user to the information handling system; and automatically initiate a secure session between the copy of the local application and the remote service when the user is authenticated to the information handling system.

Abstract: A mobile station, an access point, a gateway apparatus, a base station, and a handshake method thereof for use in a wireless network framework are provided. The wireless network framework comprises a first wireless network comprising the access point, and a second wireless network comprising the gateway apparatus and base station. There is an IP security tunnel between the access point and the gateway apparatus. When the mobile station handovers from the first wireless network to the second wireless network, it transmits a master session key to the gateway apparatus via the access point and the IP security tunnel. Additionally, when the mobile station handovers from the second wireless network to the first wireless network, it transmits a master session key to the access point. As a result, the authentication time, which is needed in handover procedure between the first wireless network and the second wireless network, is reduced effectively.

Abstract: According to an embodiment, a communication apparatus includes a security control unit. The security control unit establishes first and second secure communication channels to a first server which manages communication security keys and second server which provides a service regarding a smart meter, respectively when operation to the smart meter is started, performs mutual authentication with the first server and acquire a first key from the first server via the first secure communication channel, and relays mutual authentication with the first server and acquisition of a second key from the first server via the first secure communication channel for the smart meter.

Abstract: This invention concerns a safe data exchange method between two devices locally connected to one another. In a preferred embodiment, the first device (10) is a security module containing a first encrypting key, said private key (PAKV) of a pair of asymmetric encrypting keys. The second device is a receiver (11) comprising at least one second encrypting key, said public key (PAKB) of said pair of asymmetric encrypting keys. Furthermore each of the devices comprises a symmetrical key (13). The first device (10) generates a first random number (A), which is encrypted by said private key (PAKV), then transmitted to the second device (11), in which it is decrypted by means of the public key (PAKB). The second device (11) generates a second random number (B), which is encrypted by said public key (PAKB), then transmitted to the first device (10), in which it is decrypted by means of the private key (PAKV).

Abstract: A hardware-based security module is used to protect an electronic device, especially a portable electronic device. The security module may determine either via timeout of a watchdog timer or via an explicit message to encrypt selected data on the electronic device. In addition, the electronic device may enter a limited function mode that only allows display of simplistic messages and supports network traffic with a recovery service. The recovery service may be able to use the network traffic to locate the electronic device. The security module may include a secure memory, a cryptographic function, a timer, and support for direct display of data on a monitor.

Abstract: A method for authenticating an entity by a verifier, the entity having an identifier, the verifier having a pair of private and public keys, comprising: sending to the entity a first random number selected by the verifier; a step wherein the entity encrypts a value by means of the public key of the verifier, said value including the first random number and an authentication datum on which the identifier of the entity depends; and the entity of said encrypted value sending a reply to authenticate said entity. The invention can be applied to the field of low-cost cryptography, especially the field of radio-identification.

Abstract: The invention relates to a computer implemented method for performing a user authentication, wherein an asymmetric cryptographic key pair is associated with the user, said key pair comprising a public key and a private key, wherein the method comprises selecting the user to be authenticated using a pseudonym of said user, wherein said pseudonym comprises the public key of the user, the method further comprising performing a cryptographic authentication of the user using the asymmetric cryptographic key pair.

Abstract: A method includes receiving an authentication certificate of a voice mail account holder and/or an authentication certificate of a caller wanting to leave a voice mail message the holders' voice mail account. A voice mail apparatus that provides voice mail service for the voice mail account holder performs such receiving. The account holder and/or the caller are authenticated after receiving the authentication certificate of the party being authenticated. Authenticating the account holder and/or the caller is performed using authentication information contained within the respective certificate. After such authentication is successfully performed, a voice mail message record can be created in the account of the account holder. Such creating includes allowing the caller to store the message in the account of the account holder in addition to associating authenticated identification information of the caller with the message and/or providing authenticated identification of the account holder to the caller.

Abstract: An authentication and mass subscriber management technique is provided by employing a key table derived as a subset of a larger key pool, a network edge device, and authentication tokens attached on both the network edge device and on a subscriber's computing device. The network edge device and subscriber's computing device are provided with secure, tamper-resistant network keys for encrypting all transactions across the wired/wireless segment between supplicant (subscriber) and authenticator (network edge device). In an embodiment of the invention, a secure, secret user key is shared between a number of subscribers based upon commonalities between serial numbers of those subscribers' tokens. In another embodiment of the invention, a unique session key is generated for each subscriber even though multiple subscribers connected to the same network connection point might have identical pre-stored secret keys.

Abstract: A method for establishing an encrypted communication channel between a first apparatus and a second apparatus by using a session management apparatus. The method includes: establishing a first encrypted communication channel between the session management apparatus and the first apparatus by performing mutual authentication between the session management apparatus and the first apparatus; establishing a second encrypted communication channel between the session management apparatus and the second apparatus by performing mutual authentication between the session management apparatus and the second apparatus; and exchanging key information between the first apparatus and the second apparatus via the first encrypted communication channel and the second encrypted communication channel so as to establish an encrypted communication channel between the first apparatus and the second apparatus.

Abstract: A method for securely altering a platform component is provided, comprising: assigning certificates for public encryption and signature verification keys for the device; assigning certificates for public encryption and signature verification keys for an upgrade server; mutually authenticating a device containing the platform component and the upgrade server; causing the device and the upgrade server to exchange a session key; and providing an alteration to be made to the platform component from the upgrade server to the device using the session key.

Abstract: A wireless device may perform a local authentication to reduce the traffic on a network. The local authentication may be performed using a local web server and/or a local OpenID provider (OP) associated with the wireless device. The local web server and/or local OP may be implemented on a security module, such as a smartcard or a trusted execution environment for example. The local OP and/or local web server may be used to implement a provisioning phase to derive a session key, associated with a service provider, from an authentication between the wireless device and the network. The session key may be reusable for subsequent local authentications to locally authenticate a user of the wireless device to the service provider.

Abstract: The embodiments of the present disclosure disclose an authentication method, a system, a server, and a user node are disclosed herein. The method includes: generating, by a server, a server session key according to the identity information, at least one login information parameter, and the validity period included in the login information, generating at least one session key parameter of a user node according to the generator point of the algebraic curve, and sending at least one session key parameter of the user node to the user node; generating, by the user node, a user node session key according to at least one session key parameter of the user node; performing, by the server and the user node, mutual authentication according to the session keys. The authentication solution under the present disclosure is simple and practicable, and is also applicable to authenticating the user node in a grid computing platform.

Abstract: Systems and methods are provided for securing at least one mobile device. A server includes a controller and a non-transitory computer readable medium storing instructions executable by the controller. The executable instructions are configured to perform a method in which a secure communications session is established with a user and the user is allowed to input a list of a plurality of security actions to be performed at a mobile device associated with the user. A secure communications session is established with the mobile device, and the list of the plurality of security actions is provided to the mobile device simultaneously as a single instruction set.

Abstract: A method, device, system and computer program for providing a transport distribution scheme for a security protocol are disclosed. A first packet data connection is established to a remote node for transmitting packet data over a network with a security protocol. An authentication procedure is performed with the remote node via the first packet data connection for establishing a security protocol session with the remote node. At least one security parameter is negotiated with the remote node for transmitting packets through the first packet data connection. A second packet data connection is established to the remote node, and at least one security parameter is negotiated with the remote node for use with the second packet data connection. The first and second packet data connections are handled as packet data subconnections associated with the security protocol session.

Abstract: Disclosed herein are systems, methods, and tangible computer readable-media for detecting synthetic speaker verification. The method comprises receiving a plurality of speech samples of the same word or phrase for verification, comparing each of the plurality of speech samples to each other, denying verification if the plurality of speech samples demonstrate little variance over time or are the same, and verifying the plurality of speech samples if the plurality of speech samples demonstrates sufficient variance over time. One embodiment further adds that each of the plurality of speech samples is collected at different times or in different contexts. In other embodiments, variance is based on a pre-determined threshold or the threshold for variance is adjusted based on a need for authentication certainty. In another embodiment, if the initial comparison is inconclusive, additional speech samples are received.

Abstract: Various embodiments provide an ability to isolate execution of trusted content and/or script from execution of untrusted content and/or script. Separate contexts and/or execution environments can be used for the trusted content and untrusted content, respectively. A trusted context and/or execution environment associated with execution of trusted content can be configured to enable access to sensitive resources associated with a computing device. An untrusted context and/or execution environment associated with execution of untrusted content can be configured with limited and/or no access to the sensitive resources. Alternately or additionally, data generated within the untrusted context can be transferred to the trusted context in a benign manner.

Abstract: A domain key is securely distributed from a device in an existing network to a device outside the network. Each device generates the session key on its own using the first random number, the second random number, the Personal Identification Number, and the same key generation function. The device in the existing network sends the domain key encrypted with the session key to the other device.

Abstract: Systems and methods for authenticating a request submitted from a client device through a third party content provider to an electronic entity are described. In one embodiment, a method includes providing a trusted script to the third party content provider, passing a trust token to the third party content provider and to the client device, and, in response to a request submitted from the client device through the third party content provider, validating the trust token associated with the request with the token passed to the client device, and processing the request. The trusted script is configured to create a trusted window on the third party Web page displayed on the client computing device, receive a trust token from the electronic entity through the trusted window, and associate the trust token with requests submitted from the client computing device through the third party content provider to the electronic entity.

Abstract: Apparatuses, articles, methods, and systems for secure platform voucher service for software within an execution environment. An embodiment includes the ability for a Virtual Machine Monitor, Operating System Monitor, or other underlying platform capability to restrict memory regions for access only by authenticated, authorized and verified software components. A provisioning remote entity or gateway only needs to know a platform's public key or certificate hierarchy to receive verification for any component. The verification or voucher helps assure to the remote entity that no malware running in the platform or on the network will have access to provisioned material. The underlying platform to lock and unlock secrets on behalf of the authenticated/authorized/verified software component provided in protected memory regions only accessible to the software component.

Abstract: The invention discloses a method for implementing encryption and transmission of information and system thereof. The method comprises the following steps when a sender sends information to a receiver: a client of the sender encrypts the information by using a unique identifier of a receiver identity as a public key; the sender sends the encrypted information to the receiver; the receiver receives the encrypted information, and a client of the receiver performs decryption by using a user private key; wherein the client of the receiver obtains the user private key by one-off registration and the user private key matches with the unique identifier of the receiver identity. The system comprises an information transmission platform, a sender and a receiver connected to each other by the information transmission platform, clients provided in the sender and the receiver, and a registration component.

Abstract: A method of establishing secure communication between a first mobile computing device and a second mobile computing device includes receiving a first request from the first mobile computing device to securely communicate with the second mobile computing device via a Wi Fi hot spot, verifying that the first mobile computing device is trusted, generating a public key and a private key based on a trusted certificate, sending the private key to the first mobile computing device via the Wi-Fi hot spot, receiving a second request from the second mobile computing device to securely communicate with the first mobile computing device, verifying that the second mobile computing device is trusted, and sending the public key to the second mobile computing device.

Abstract: In general, this disclosure relates to maintaining security between an optical network terminal (ONT) and an optical network aggregation device in an Active Ethernet network. An optical network aggregation device includes one or more optical Ethernet switches that can be adaptively configured to support authentication of one or more ONTs. For example, the optical network aggregation device may include a controller with an authentication unit for managing ONT authentication and an optical Ethernet interface for transmitting and receiving data over the optical network. The authentication unit may exchange authentication request messages via the optical Ethernet interface with an ONT and grant the ONT access to the provider network based on the exchange, thereby preventing rogue devices from gaining access to the provider network.

Abstract: A computer-implemented method is provided for controlling use of a file on a user device. The method includes transmitting authentication information to a system and downloading the file from the system over the network upon successful authentication by the system. The method also includes limiting access of the file to a client application of the user device and preventing altering of the file, printing of the file and opening of the file outside of the client application. Notes corresponding to the file can be stored in a local storage area.

Abstract: Communication across domains is described. In at least one implementation, a determination is made that an amount of data to be communicated via an Iframe exceeds a threshold amount. The data is divided into a plurality of portions that do not exceed the threshold amount. A plurality of messages is formed to communicate the divided data across domains.

Abstract: A method, data processing system and program product is provided for performing double authentication for controlling disruptive operations on storage resources generated by a system administrator. A first request is received from a first user for generation of a first key. A first key is generated, provided to the first user and associated with the storage resource. An input is received from the administrator, the input comprises a second key and a command for performing the disruptive operation. The second key and the first key are compared. It is verified that the administrator is authorized as an administrator of the storage resource. The disruptive operation is performed on the storage resource if the second key and the first key match and the administrator is authorized. Otherwise, the performance of the disruptive operation is denied.

Abstract: Provisioning VLAN services in a network patching system includes receiving a request to provide a VLAN service to an individual communication channel, determining whether a switch connector port connected to the individual communication channel via a patch cord is configured to provide the requested VLAN service, and initiating the requested VLAN service to the individual communication channel in response to determining that the switch connector port is configured to provide the requested VLAN service. Verification that a user associated with the individual communication channel is authorized to access the requested VLAN service may be performed prior to initiating the requested VLAN service. An administrator may be notified that a VLAN service has been requested and/or initiated. The user associated with the communication channel may be notified when the requested VLAN service has been initiated.

Abstract: A method of authenticating a client to a service via a network includes retrieving a client ID and a lockstep code from a token interfaced with a client device, sending the client ID and the lockstep code to an authentication server as part of a verification request, at the authentication server, comparing the lockstep code to a confirmation lockstep code relating to the client ID, based on the comparison, sending an authentication message from the authentication server, at the authentication server, generating a new confirmation lockstep code, sending the new confirmation lockstep code to the client device, and updating the lockstep code of the token to an updated lockstep code that matches the new confirmation lockstep code.

Abstract: Secrecy of printed matter is raised and charges for a storing area are more accurately charged. According to the invention, a printing apparatus is instructed so as to store print data corresponding to a print request into one of a plurality of storing areas. The print data is transmitted to the printing apparatus. The user is notified of authentication information corresponding to the print data stored in one of the plurality of storing areas.

Abstract: In order to restrict a destination of data for security and facilitate acquisition of the data at the destination, a conference system includes an MFP and a projector, wherein the MFP prestores data for display in an HDD and includes an access key generating portion to generate an access key for an access to the display data and a data transmitting portion to transmit the display data on the condition that the access key is received from a PC, and the projector includes a wireless communication portion to wirelessly communicate with PCs within a predetermined distance, a projecting control portion to display the data stored in the HDD in the MFP, an access key acquiring portion to acquire the access key, and an access key transmitting portion to cause the wireless communication portion to transmit the access key when receiving a request from the PC via the wireless communication portion.

Abstract: A mobile node and its home system generate synchronized time-based codes at periodic time intervals. Each time-based code is valid for a predetermined time period. To facilitate anonymous operation when roaming, the mobile node identifies itself with a coded identifier instead of a public identifier. The coded identifier used at a given time includes the time-based code that is valid for that given time. To authenticate the mobile node, a serving system receives authentication information from the mobile node and forwards the authentication information to a home system. The authentication information includes the current time-based code and a timestamp. The home system identifies the mobile node from the current time-based code and the timestamp. The home system then uses the authentication information to authenticate the mobile node.

Abstract: The present invention provides an information processing device, an authentication system, etc. that save a server the trouble of updating a database, etc., even when a software module in a client device is updated, and that are capable of verifying whether software modules that have been started in the client device are valid. The terminal device A100 holds private keys 1 and 2, and performs authentication processing with the terminal device B101 using the private key 2. The private key 1 has been encrypted such that the private key 1 is decryptable only when secure boot is completed. The private key 2 has been encrypted such that the private key 2 is decryptable using the private key 1 only when the application module X that has been started is valid. When the authentication processing is successful, the terminal device B101 verifies that the terminal device A100 has completed secure boot and the application module X that has been started in the terminal device A100 is valid.

Abstract: An interactive multimedia presentation playable by a presentation system includes a media content component and an interactive content component. The interactive content component includes one or more applications, which provide instructions for organizing, formatting, and synchronizing the presentation of interactive objects to a user. Prior to playing the interactive multimedia presentation, an entity responsible for authoring or publishing one or more of the applications is digitally identified and authenticated, or it is determined that the applications are unsigned. Prior to and/or during play of the interactive multimedia presentation, authorization for performing certain actions (such as executing certain application instructions, especially those that access functionality of the presentation system, computer-readable media, or external networks) is granted via a permission-based model.

Abstract: Methods and apparatuses that enroll a wireless device into an enterprise service with a management server addressed in a management profile are described. The enrollment may grant a control of configurations of the wireless device to the management server via the management profile. In response to receiving a notification from the management server, a trust of the notification may be verified against the management profile. If the trust is verified, a network session may be established with the management server. The network session may be secured via a certificate in the management profile. Management operations may be performed for management commands received over the secure network session to manage the configurations transparently to a user of the wireless device according to the control.

Abstract: The present disclosure is directed to systems and methods including accessing a first private value, generating a first intermediate value based on the first private value, receiving a second intermediate value that is based on a second private value, generating a first comparison value based on the second intermediate value, receiving over the network a second comparison value that is based on the first intermediate value, comparing the first comparison value and the second comparison value to generate a result, and displaying the result, the result indicating that the first private is greater than the second private value when the first comparison value is less than the second comparison value, and the result indicating that the first private value is less than or equal to the second private value when the first comparison value is greater than the second comparison value.

Abstract: A method for protecting a digital document and user data typed into a digital document is presented. The method comprises computation of an authentication tag when the document is sent from a server. A similar authentication tag is computed when the document is shown on a client. When another document referenced in the document is requested by the client from the server, the authentication tag computed by the client is attached to the request for that other document. The server receiving the request compares the authentication tag it computed with the one it received to verify if the request came from an authentic copy of the document. The method is suitable for protection of online banking, online investment, online shopping, and other electronic applications.

Abstract: Disclosed are various embodiments of a system. In one embodiment, among others, a method comprises intercepting a communication between a first party and a second party in a communication forum, the communication including a first party proxy information as an intended recipient information. The method further comprises accessing a communication pair using the intended recipient information, the intended recipient information being associated with a second party proxy information, the second party proxy information being associated with a second party information. Additionally, the method comprises determining whether the identity of the sender is valid.

Abstract: An initiating user receives an authentication code and an associated confirmation word from a server system in response to an authentication code request. The initiating user initiates a communication session with an authenticating user and provides the authentication code to the authenticating user without providing the associated confirmation word to the authenticating user. The authenticating user is only able to obtain the associated confirmation word if the authentication code corresponds to an authentication code previously generated by the server system for the initiating user and no usage limitation on the authentication code has been reached. Subsequently, the initiating user receives a confirmation word from the authenticating user. The initiating user provides action instructions to the authenticating user when the confirmation word provided by the authenticating user corresponds to the associated confirmation word.

Abstract: A password-based cryptographic method is effected between a first party with a specified identity and secret password and a second party with a master secret. During a registration phase, a long-term password-based public key is generated for the first party from its password and the master secret of the second party. Subsequently, to generate matching keys, asymmetric or symmetric, for the parties for a specific interaction, the first party generates short-term secret x, and computes a short-term password-based public key that requires for its computation direct knowledge of the first party's password and secrets x; the second party then transforms this short-term password-based public key into an clement X, complimentary to x, by using its master secret and at least a first-party-specific constituent of the first party's long-term password-based public key. The secret x and element X are then used to provide matching keys for the parties.

Abstract: An information processing apparatus is provided which includes a plurality of encryption algorithm units which are respectively capable of performing mutual authentication with an external device by respectively using an encryption method or a cipher key being different from one another; and a data memory unit which stores a plurality of cipher-specific information being provided to each of the encryption algorithm units and including a cipher type which specifies an encryption method used by each of the encryption algorithm units and disabling control information for disabling at least one encryption algorithm unit among the plurality of encryption algorithm units; wherein at least a first encryption algorithm unit among the plurality of encryption algorithm units disables another encryption algorithm unit in accordance with the disabling control information which is stored at the data memory unit when a mutual authentication with an external device succeeds.

Abstract: An aggregation system, process, article, and necessary intermediates, illustratively the system includes: a device capable of both networking and executing software programs, the device programmed from memory so that the aggregation apparatus: connects to a plurality of servers via the Internet, and authenticates itself with each of the plurality of servers, and retrieves information from each of the plurality of servers, and parses the information from each of the plurality of servers so as to produce an aggregation of parsed information, and renders the aggregation as output.

Abstract: An authentication method authenticates between subscribers of a communications system using an asymmetric elliptic curve encryption algorithm. The method involves providing a first and at least one second subscriber having a first or second secret key known only to the respective subscriber and a public key; authenticating an inquiry transmitted by the first subscriber with respect to the validity of the first certificate contained therein and associated with the first subscriber; calculating the response of the second subscriber associated with the inquiry; randomized encryption of the calculated response and a second certificate associated with the second subscriber using the public key; decryption and authentication of the response transmitted by the second subscriber with respect to the validity of the second certificate contained therein.

Abstract: A method for verifying the identity of a communication partner, in particular in real-time communications, wherein a caller (A) sends a message towards a callee (B), and wherein the caller (A) attaches a self-signed certificate to the message, characterized in that the caller (A) and the callee (B) are part of a web-of-trust, wherein certificates of users within the web-of-trust are stored by one or more key-servers (3), wherein trust relationships between users within the web-of-trust are employed to compute a trust-chain between the caller (A) and the callee (B) based upon the certificate attached to the message and upon the callee's certificate, and wherein the further processing of the message received by the callee (B) is based on the length of the derived trust-chain. Furthermore, a corresponding system is described.

Abstract: Machine, method for use and method for making, and corresponding products produced thereby, as well as data structures, computer-readable media tangibly embodying program instructions, manufactures, and necessary intermediates of the foregoing, each pertaining to digital aspects of a computerized aggregation system. The system can include a user computer system interposed between a segment of a network allowing communication between the user computer system and at least one server system, and other segments allowing communication between the user computer system and a plurality of third party server systems. The one server system enables the user computer system to access the plurality of other servers. The access permits forming an aggregation of information obtained from the third party server systems.

Abstract: A printing device includes a processor, an attribute managing part configured to be activated by the processor to communicate with a host device and to control an authentication printing job received from the host device, a memory configured to store authentication printing job data and user information extracted from the authentication printing job data, and a deleting part configured to delete the authentication printing job data and the user information stored in the memory based on predetermined results of communication between the attribute managing part and the host device. As a result, the user is not required to consider whether the time for which the authentication printing data is stored should be extended.

Abstract: A security module is provided in a data recording medium, data to be written to the data recording medium is encrypted with an content key different from one data to another, and the content key is safely stored in the security module. Also, the security module makes a mutual authentication using the public-key encryption technology with a drive unit to check that the counterpart is an authorized (licensed) unit, and then gives the content key to the counterpart, thereby preventing data from being leaked to any illegal (unlicensed) unit. Thus, it is possible to prevent copyrighted data such as movie, music, etc. from being copied illegally (against the wish of the copyrighter of the data).