Method for secure exchange of data over an ad-hoc network using an Xcast broadcast service and associated node

A method for the secure exchange of data over an ad-hoc network implementing an Xcast broadcasting service and an associated node are disclosed. The method includes providing a security graph for the network and a communication graph for the network, routing a data item between the sender node sending the data and each receiver node receiving the data along a secure route on the security graph. The method also includes generating, between one relay node and a subsequent relay node of the secure route, an appropriate message, containing the data protected in accordance with a security association shared between the relay node and the subsequent relay node. The method further includes routing the message from the relay node to the subsequent relay node along a communication route on the communication graph.