A method for reserving resources in a packet communication network, preferably an IP protocol network. The method includes sending an active packet containing a request for reservation of resources for an active data flow, receiving the packet by an active node in the network, and reserving resources of the node according to the request. In this method, an active packet communication network node, in particular an IP active router, reserves resources for processing data of an active data flow according to a resource reservation request for this active data flow contained in this active packet received by the node.