Patent ID: 8478984

Claim:
A data encryption apparatus for encrypting, in a unit of a predetermined encryption data size, data transferred from a first apparatus to a second apparatus, the data encryption comprising: a transfer request sending unit that establishes, upon receiving from the second apparatus a first data transfer request indicating a first receivable size, a second receivable size being equal to or greater than the first receivable size and being a multiple of the predetermined encryption data size, and that sends to the first apparatus a second data transfer request indicating the second receivable size thus established; a data encrypting unit that receives data of the second receivable size from the first apparatus in response to the second data transfer request sent by the transfer request sending unit, and that encrypts, in the unit of the predetermined encryption data size, the data received from the first apparatus; and a data sending unit that sends the data encrypted by the data encrypting unit to the second apparatus in units of the first receivable size, and upon remaining unsent data below the first receivable size after the data sending unit that sends the data, the data sending unit combining the unsent data with subsequent encryption data and sending the combined data to the second apparatus, the subsequent encryption data being subsequently encrypted by the data encrypting unit, wherein the data sent from the first apparatus contains data type information indicating a type of the data, and the data encrypting unit determines based on the data type information whether to encrypt the data, and encrypts the data upon determining to perform encryption, wherein the data sent from the first apparatus contains data type information indicating a type of the data, and the data encrypting unit determines based on the data type information whether to encrypt the data, and encrypts the data upon determining to perform encryption.