摘要:
A theft prevention system capable of preventing theft of a target object by disabling the authorized key of the target object in the case where the authorized key has been stolen. When the authorized key is lost, a mobile telephone instructs a vehicle control device to set a warning mode. On receipt of this warning mode instruction, the vehicle control device sets warning mode, generates an electronic key, and transmits the generated electronic key to the mobile telephone, which receives and stores the electronic key. Once the warning mode is set in the vehicle, locking and unlocking are only possible using the electronic key. If the authorized key is found, the mobile telephone instructs the vehicle control device to set the normal mode. Upon receipt of this normal mode instruction, the vehicle control device sets the normal mode in the vehicle.
摘要:
A theft prevention system capable of preventing theft of a target object by disabling the authorized key of the target object in the case where the authorized key has been stolen. When the authorized key is lost, a mobile telephone 100 instructs a vehicle control device 300a to set a warning mode. On receipt of this warning mode instruction, the vehicle control device 300a sets warning mode, generates an electronic key, and transmits the generated electronic key to the mobile telephone 100, which receives and stores the electronic key. Once the warning mode is set in the vehicle, locking and unlocking are only possible using the electronic key. If the authorized key is found, the mobile telephone 100 instructs the vehicle control device 300a to set the normal mode. Upon receipt of this normal mode instruction, the vehicle control device 300a sets the normal mode in the vehicle. Once the normal mode is set in the vehicle, locking and unlocking are only possible using the authorized key.
摘要:
A parameter generation apparatus for generating parameters causing no decryption error for an NTRU cryptosystem so that an encrypted communication can be carried out between an encryption apparatus and a decryption apparatus in a secure and reliable manner, is comprised of: a provisional parameter generation unit operable to generate a set of provisional parameters that do not cause any decryption errors, based on error condition information that is provided in advance, said error condition information indicating a condition for causing no decryption error; and an output parameter generation unit operable to generate an output parameter that does not cause any decryption errors, using said set of provisional parameters, based on a lattice constant that is calculated from said set of provisional parameters.
摘要:
In an encrypted communication system that includes a first and a second device, the first device encrypts a key using a public key of the second device to generate 1st encrypted data, which is then transmitted to the second device, receives 2nd encrypted data from the second device, which is then decrypted using a secret key of the first device to obtain a 2nd key, and generates, based on the 1st and 2nd keys, a 1st encryption key for use in communication with the second device. The second device encrypts a 3rd key using a public key of the first device to generate the 2nd encrypted data, which is then transmitted to the first device, receives the 1st encrypted data, which is then decrypted using a secret key of the second device to obtain a 4th key, and generates, based on the 3rd and 4th keys, a 2nd encryption key for use in communication with the first device. The first and second devices perform encrypted communication using the 1st and 2nd encryption keys.
摘要:
An encroption transmission apparatus and an encryption reception apparatus avoid attack that takes advantage of re-transmission request. A server apparatus encrypts a content key five times, thereby generating five encrypted content keys, calculates a hash value of the content key, and transmits the five encrypted content keys and the hash value. An image playback apparatus receives the five encrypted content keys and the has value, decrypts the five encrypted content keys thereby generating five content keys, calculates hash values each corresponding to the generated content keys, and compares the calculated hash values with the received hash value respectively. If at least one of the five calculated hash values matches the received hash value, the corresponding content key is considered correct. Conversely, if none of the five calculated hash values matches the received hash value, it is considered a decryption error.
摘要:
A computer system that makes it difficult to analyze the content of a calculation. A power operation unit (262) performs the following operations using the input data “a” and “b”: ga=ga mod n, gb=gb mod n. Next, a multiplication unit (264) performs the following calculation using ga and gb: gab=ga×gb mod n. Next, a discrete logarithm calculation unit (266) calculates ci mod pi−1 to satisfy gab=gci mod pi (i=1, 2, 3, . . . ,k). Next, a CRT unit (267) calculates “c” to satisfy ci=c mod pi−1 (i=1, 2, 3, . . . ,k) using the Chinese remainder theorem CRT.
摘要:
A content-related information delivery system for delivering information related to a content to a user-owned apparatus. The system is composed of a playback apparatus and a server. The playback apparatus monitors a current playback position of the content during playback, generates playback position information specifying a segment of the content, and transmits the generated playback position information to the server. The server receives the playback position information from the playback apparatus, acquires information related to the segment of the content specified by the received playback position information, and transmits the acquired related information to the user-owned apparatus.
摘要:
A content reproduction system that allow the user to rent or purchase any desired contents for reproduction without depending on a predetermined type of information of the user. The content reproduction system includes: a recording medium storing a license ticket including an encrypted master key; and a reproduction apparatus that receives from the user a request for a selected content and the information of the selected content, acquires distribution content information corresponding to the selected content, stores it in association with the license ticket into the recording medium. When reproducing the content, the reproduction apparatus generates a content using an encrypted content decryption key and an encrypted content that are contained in the distribution content information, and using a master decryption key information corresponding to the distribution content information, and reproduces the generated content.
摘要:
A content reproduction system that allow the user to rent or purchase any desired contents for reproduction without depending on a predetermined type of information of the user. The content reproduction system includes: a recording medium storing a license ticket including an encrypted master key; and a reproduction apparatus that receives from the user a request for a selected content and the information of the selected content, acquires distribution content information corresponding to the selected content, stores it in association with the license ticket into the recording medium. When reproducing the content, the reproduction apparatus generates a content using an encrypted content decryption key and an encrypted content that are contained in the distribution content information, and using a master decryption key information corresponding to the distribution content information, and reproduces the generated content.
摘要:
An encrypted communication system, capable of performing processing with the speed higher than the conventionally achieved speed, has an encryption device and a decryption device which share parameters that satisfy p=3 and q=2ˆk (k: an integer of 2 or greater) (S161), where the decryption device generates a public key and a private key using the parameters (S162-S165), the encryption device encrypts a plain text using the public key (S166-S170), and then, the decryption device decrypts the encrypted text using its own private key (S171-S173).