Abstract: A device for the securing of information systems, notably for a system used in the field of microcomputers, comprising at least one SCSI port having means for the enciphering of confidential information travelling through the system and comprising a peripheral communicating with the information system by an SCSI bus that has an interface between the SCSI bus and a bus internal to the peripheral, placing information management and storage means in a state of communication with the enciphering means contained in the peripheral as well as with an interface between a user and the peripheral, making it possible to provide the security services for the confidential information travelling through the peripheral, independently of the standards of the bus and operating system used by the information system.