An apparatus includes a first-processor, and a programmable integrated circuit coupled to the first-processor; a second-processor, and a memory coupled to the second-processor, the second-processor being configured to access the first-processor; and a third-processor to manage the first-processor, wherein the first-processor is configured to write, to the rewritable-integrated circuit, a computation circuit to perform computation according to information from the second-processor, and an encryption circuit to generate encrypted data by encrypting a computation result computed by the computation circuit, by using an encryption key for the computation circuit, the third-processor is configured to manage the encryption key in association with the computation circuit and notify the second-processor of the encryption key for the computation circuit, and the second-processor is configured to read out the encrypted data from the memory for storing the encrypted data, and decrypt the read encrypted data by using the encryption key notified from the third-processor.