A method, a device and a program are provided for processing data. The method is implemented within an intermediary module. The data is transmitted between a customer module and a server module connected through a communications network. The method includes: receiving, from one among the customer and server modules, an intermediation request identifying an operation of intermediation to be performed relative to a stream of encrypted data exchanged between the customer module and the server module; and processing relative to said encrypted data as a function of said operation of intermediation.