Method for enabling a user already connected to a virtual private network to communicate with a communication device not belonging to this virtual private network and corresponding network access server

The invention relates notably to a method for enabling a user registered in an Network Access Server as already connected to a Virtual Private Network to communicate with at least a communication device not belonging to the Virtual Private Network. The Network Access Server enables access over a data communication network to the communication device as well as to a plurality of Virtual Private Networks. According to the invention, the method consists in sending messages belonging to a communication between the user and the communication device over a logical channel between the Network Access Server and the communication device, where the logical channel refers to an identifier of the Virtual Private Network.