Abstract: Electric field communication that adopts a metal as a communication medium is performed. An electric field communication system communicating through an electric field, includes: a communication medium made of a material capable of transmitting the electric field; a first transmitter that generates an electric field dependent on a potential difference between a first electrode, which is disposed on a side of the communication medium and is connected to the communication medium via a coupling capacitance, and a second electrode connected to an earth ground via a coupling capacitance, with the first electrode being connected on a signal side of the transmitter, and the second electrode being connected on a ground side of the transmitter; and a first receiver disposed in contact with the communication medium, wherein the first transmitter and the first receiver communicate with each other through the electric field via the communication medium.

Abstract: Provided is a kernel program and so on capable of enhancing the confidentiality of data memorized in a storage device without using a file system on an OS kernel level. The kernel program is mounted on a computer operable to input and output data between an application program and a storage device, and causes the computer to function as: a socket establisher establishing a socket for connecting with the application program; a relational database operable to input and output data from/to the storage device through a device driver; and an access controller inputting a command from the application program through a message structure of the socket then to output the command to the relational database and inputting an execution result from the relational database then to output the execution result through a message structure of the socket to the application program.

Abstract: Provided is a kernel program and so on capable of enhancing the confidentiality of data memorized in a storage device without using a file system on an OS kernel level. The kernel program is mounted on a computer operable to input and output data between an application program and a storage device, and causes the computer to function as: a socket establisher establishing a socket for connecting with the application program; a relational database operable to input and output data from/to the storage device through a device driver; and an access controller inputting a command from the application program through a message structure of the socket then to output the command to the relational database and inputting an execution result from the relational database then to output the execution result through a message structure of the socket to the application program.