Abstract: A central processing unit (GT) comprises a private key in secrecy, and an encryption engine. Before the GT executes software, a license added to the software is entered into the GT. The license includes information obtained by encrypting a code encryption key used when the software is encrypted with a public key pairing with the private key. When the license is entered, the encryption engine obtains the code encryption key by decrypting the license with the private key, and decrypts the software with the code encryption key.

Abstract: A user terminal has a file exchanging capability provided with a transmission control unit, a reception control unit, and an entry unit. As the transmitting capability by the transmission control unit, the entry unit makes an entry in an external specific server. Unless a digital certificate can be obtained for an individual public key through the server, contents is unavailable. When contents are transmitted or enabled for transmission, the transmission control unit assumes that a signature has been placed without fail. The reception control unit checks the signature of the received contents, and controls the contents to be unavailable unless a correct signature has been placed.

Abstract: An LA (License Agent) (or a license chip having the same function as the LA) is disposed in a PC (Personal Computer), a content distribution server, and a medium attached to a PD (Private Device or Portable Device) that use a license for electronic data. A content and electronic data are encrypted corresponding to a license. The encrypted content and electronic data are distributed among them. However, the license is distributed between the LAs as safe communication means. Thus, the license can be correctly managed and transferred.

Abstract: Disclosed is a database management control system based on the client/server architecture including a client process operating on a client machine and a server process operating on a server machine, which prevents resources from remaining allocated without being properly relinquished. When a client makes a request for connection to the server, a starting order identifier notifying device notifies the server process of a starting order identifier indicating the starting order of an operating system on which the client process operates. An executing entity search device of the server process searches for executing entities under control of an executing entity control device, which are correlated to the same network address as a network address of the client machine on which the client process operates.

Abstract: The present invention discloses a message communication system and a distribution system. The feature of the present invention lies in various functions in the reception server, which is provided between the client server and the processing server. For example, the reception server performs reference processing, update processing, redundancy processing, etc. In the claimed invention, a reception server 20 is arranged between a client process 10, and a processing server 30. A demand discrimination stage 25 is provided for discriminating a demand only for a reference process and not requiring an update of medium and exclusive resources, and a demand for a reference process and reference and update process requiring a change of condition of the resource. The demand discrimination stage 25 classifies respective message communications systems into three aspects.