초록 ▼

The protection of the transfer of data between a videotex terminal (TVX) and a server (SE) is carried out by means of an additional package (BA) connected to a video adaptor connector (PPI) of the terminal (TVX). In a presession embodiment, the package acts on the switching device (AIG) of the termi

The protection of the transfer of data between a videotex terminal (TVX) and a server (SE) is carried out by means of an additional package (BA) connected to a video adaptor connector (PPI) of the terminal (TVX). In a presession embodiment, the package acts on the switching device (AIG) of the terminal by monitoring any other action on said switching equipment. The switching cabinet and the server conduct dialogue according to a predetermined sequence of operations comprising the definition of a transmitted session key encrypted in accordance with a basic key. Any anomaly occuring during this dialogue aborts the presession mode.

대표청구항 ▼

Exchanging data device comprising: (a) a videotex terminal having a switching control device, a line interface, a keyboard, a screen, a downstream video adapter connector and a power supply, (b) a package connected to said video adapter connector of said videotex terminal, said package comprising fi

Exchanging data device comprising: (a) a videotex terminal having a switching control device, a line interface, a keyboard, a screen, a downstream video adapter connector and a power supply, (b) a package connected to said video adapter connector of said videotex terminal, said package comprising first encryption/decryption means and first dialogue means constituted by: (i) a central processing unit acting as a microcontroller and having a transmission terminal and a receiving terminal connected to said switching control device of said videotex terminal, (ii) first storage means storing at least one encryption/decryption algorithm, at least one part of a basic key, a confidential code, and an authentication package code, (iii) voltage supplying means connected to said power supply of said videotex terminal, (c) a server comprising second encryption/decryption means and second dialogue means, constituted by second storage means storing said at least one encryption/decryption algorithm, at least one part of said basic key, and a server authentication code. (d) a telematic line connecting said videotex terminal and said server through said line interface of said videotex terminal, (e) said first and second encryption/decryption means of said package and said server and said first and second dialogue means of said package and said server operative in a first presession mode and in a second session mode subsequent to said presession mode, (f) wherein said presession mode includes: (i) carrying out a predetermined sequence of operations including inputting of said confidential code by a user via said keyboard of said videotex terminal, checking said confidential code in said package for validity, carrying out mutual authentication validity checks between said package and said server using said package and server authentication codes, (ii) sending from said server to said package a session key ciphered according to said basic key, said session key being then stored in said first storage means of said package, said central processing unit of said package acting on said switching control device of said videotex terminal to inhibit a linking between said keyboard and said line interface of said videotex terminal and monitoring any action on said switching control device having an origin external to said package, any such action leading to the presession mode being aborted, (g) said session mode including exchanging messages ciphered/deciphered according to said session key.