According to one embodiment, a master key management device generates, by using a first secret key stored in a first storage unit and a third public key, a re-encryption key used to re-encrypt a second secret key which is stored in a second storage unit and which is encrypted with a first public key to the second secret key encrypted with the third public key. The socket of the present invention includes a housing and a first plug, which is provided in an insertion part of the housing. The ink cartridge is stored inside the individual box so that the ink supply port is at the top when the box is in the normal upright position. The field programmable gate array based processing elements have the capability to alter data passing through it to and from an external interconnect fabric or device.