Abstract: The invention concerns an encryption method and system particularly adapted to securing email. It makes it possible to prevent the encryption of the body of a message from generating certain symbols, called control characters, that can cause undesirable phenomena during the transmission of the message. The encryption uses a pseudo-random generator, pre-initialized in a known way. The successive values provided by this generator are used to encode the successive symbols in the body of the message, any control characters present in the plaintext message being transmitted without being modified.

Abstract: The invention concerns a server for management of authentication (S) and devices interconnected between each computer equipment needing to be made secure and the communication network. It enables to make secure said network in a distributed and dynamic manner. The device intercepts communications between a computer equipment (A) whereto it is connected and the network and enables to obtain, by means of an authenticating module, data concerning a user (U) and to define a security level for said device. The authentication management server (S), connected to the network, processes said data and said security level and authenticates the user (U). The server (S) manages the authentication and transmits to the network devices security parameters. Said parameters are stored and processed by the network devices.

Abstract: The invention pertains to a method for making secure a generator generating pseudo-random numbers. The generator is characterized by its internal status. The generator includes: a first storage zone containing status bits, representing the internal status of the generator; a computing unit performing arithmetic operations on the status bits to produce the pseudo-random numbers and to modify the status bits; a second storage zone containing the pseudo-random numbers; a single output for reading the pseudo-random numbers contained in the second storage zone. The method according to the invention includes the step of irreversibly and unconditionally inhibiting, in particular via logical and/or mechanical and/or electronic means, the reading and the writing of the status bits from outside the generator, including via the single output.