Multiplexing unit, system and method for communication in a computer network

Multiplexing unit for communication in a computer network between a plurality of client machines (16) that supports client programs and several servers (17) that support application programs, can client programs and application incompatible, comprising the indicated media unit shipping and conversion means, characterized in that it comprises: - for each type of client machine (16), a management module input (18) receiving requests (20) from client programs and transmits the responses (21): - for a server (17) or a group of servers, a management module output (19) transmitting to the server the messages customers (22) that are targeted and transmit responses (21) management modules input (18) of client machines (16) and by the fact that: - the sending means (24, 30, 29, 34) are connected to the management modules input (18) and output (19) and suitable to define the identity deal least one management module outlet (19) for processing a request (20) and to determine the identity of the client machine (16) to which the message (23 ) from the target server (17) should be addressed; - The conversion means (28, 33, 25, 31) are suitable to convert, if necessary, the content of the request (20) in a client message (22) compatible with the application program target server (17) and the content of the message (23) from the target server (17) in a response (21) compatible with the client program.