A method for the allocation of resources for the transmission, in a communications network, of a data stream from an intermediate device to a sink device, said data stream comprising a plurality of data applications packets and being transmitted from a source device to the intermediate device in the form of data transport packets according to a communications protocol.The intermediate device performs the following steps: reception of data transport packets according to the communications protocol; obtaining application time-stamp information included in the data of the data stream contained in the data transport packets received; determining a bit rate, called an application bit rate, from said application time-stamp information obtained and a piece of information on quantity of data of the data stream received by the intermediate device; determining a value of bandwidth to be allocated as a function of the application bit rate to transmit the data stream from the intermediate device to the sink device; allocation of the value of bandwidth to be allocated to the transmission of the data stream from the intermediate device to the sink device.