Patent ID: 8326994

Claim:
A method for setting up a communications path between a first communications sub-network and a second communications sub-network by means of an intermediate sub-network, in an extended communications network, said extended communications network comprising a plurality of sub-networks, each sub-network comprising at least one tunnel end-point to enable the interconnection of said sub-network with at least one other sub-network of said plurality of sub-networks by means of at least one communications tunnel, wherein said intermediate sub-network comprises at least two tunnel end-points and in that an input tunnel end-point of said intermediate sub-network performs the following steps: receiving, from a tunnel of said input tunnel end-point, a relay activation message to set up said path, said message referring to a local relay involving said input tunnel end-point; determining, from said relay activation message, an output tunnel end-point of said intermediate sub-network involved in the local relay; activating the local relay for a part of said path between said first sub-network and said second sub-network, which enables setting up of the communications path for communications from the second sub-network to the first sub-network while selectively blocking communications relayed on the intermediate sub-network by an output tunnel end-point to the first sub-network by activation or deactivation of a relay function of the input tunnel end-point; and transmitting the relay activation message to said output tunnel end-point, wherein said relay activating step includes a step of stopping a filtering of the data frames coming from said second sub-network by elimination of an address associated with said output tunnel end-point in a frame filtering table of the input tunnel end-point, and wherein said filtering is performed on a source address field of said data frames, said field corresponding to a virtual address which is allocated by the tunnel end-point of said intermediate network having received said data frames and which represents the tunnel via which said frames have been received.