Abstract: The invention relates to a system for data exchange between at least two communication networks using the IP Internet protocol, a first network having a security level N1 higher than the security network N2 of a second network, and several terminals being connected to the first and second networks, characterised in that it comprises at least the following members: means for marking the flows based on their security level, a gateway between the first network (1) and the network (2) for carrying out a protocol interruption, and means for filtering the data flows suitable for checking the marking and to give authorisation for the broadcasting of the flow based on the relevancy between the marker and the sensitivity level of the communication, and visual means on the terminal for indicating to the user whether or not he communicates on a secured media.

Abstract: A communication system for transmission of signals between various terminal equipment connected to various intermediate equipment and connected to a communications network using the Ethernet protocol is disclosed. In one aspect, the terminal equipment is not master-controlled by a distributed clock and the intermediate equipment each includes at least one Ethernet access physical interface. In the communication system, reference time information is periodically transmitted by the reference clock generator and distributed as data transport packets to the intermediate equipment via the Ethernet access physical interface. Each intermediate equipment includes a local clock generator, the reference time information is received and processed by each intermediate equipment, so as to subordinate the local clock generator to the reference clock. The mechanism configured to process the signals is clocked by the local clock generator so as to obtain synchronous processing of the transmitted signals.

Abstract: The invention relates to a system for data exchange between at least two communication networks using the IP Internet protocol, a first network having a security level N1 higher than the security network N2 of a second network, and several terminals being connected to the first and second networks, characterised in that it comprises at least the following members: means for marking the flows based on their security level, a gateway between the first network (1) and the network (2) for carrying out a protocol interruption, and means for filtering the data flows suitable for checking the marking and to give authorisation for the broadcasting of the flow based on the relevancy between the marker and the sensitivity level of the communication, and visual means on the terminal for indicating to the user whether or not he communicates on a secured media.