Abstract: A system comprises: a representation of a network; a communications requirements file for an application to be executed by a node of said network; and a security policy file defining a security policy for said node of said network. Said files are processed to determine whether said security policy and said communication requirements are compatible.

Abstract: A system comprises: a representation of a network; a communications requirements file for an application to be executed by a node of said network; and a security policy file defining a security policy for said node of said network. Said files are processed to determine whether said security policy and said communication requirements are compatible.

Abstract: A method is presented for distributing cryptographic keys in a hierarchized network including at least one device in charge of a higher group of devices, wherein at least one of the devices of the group of devices is also in charge of a lower group of devices.

Abstract: A communications system (40) comprises a first entity (42), a first encryption device (48) and a network (46). The first encryption device (48) is adapted to decrypt, using a first decryption algorithm, data sent from a first destination to said first entity via said network (46). The first encryption device (48) is adapted to pass network metric data concerning at least one route between said first entity and said first destination to said first entity without subjecting said network metric data to said first decryption algorithm.

Abstract: A method of securing a computer comprising a microkernel and a system for interfacing with at least one virtualized operating system are presented. The microkernel includes a clock drive, a scheduler and an inter-process communication manager. The system for interfacing forms at least one virtual machine associated with each operating system and allows execution of the latter without modification. The method includes, at the level of the system for interfacing, the steps of:—intercepting any communication between a means external to the operating system and the operating system,—verifying that predefined rules of access to said external means are validated by said communication;—transmitting the communication to the recipient if the rules are validated.

Abstract: The surveillance system includes video detectors, and central aggregation device including a control device for controlling the video detectors, and a display device and image analysis device for displaying and analyzing images coming from one or more video detectors. The system further includes an intermediate aggregation device connected to a subset of the video detectors and to the central aggregation device, and including a merging device adapted to analyze the images from at least two video detectors of the subset of video detectors in order to trigger an alarm sent to the central aggregation device as a function of the result of the analysis.