A method for reserving physical resource blocks of a mobile access network, implemented by a content server configured to send a data stream requested by a terminal connected to the mobile access network with a determined level of quality. The method includes: determining a value of a number of blocks to be reserved, as a function of parameters related to the data stream, and the determined level of quality; sending a first request for reserving resource blocks, including the determined value of the number of blocks to be reserved, to a control entity of the mobile access network; and receiving a response for allocating resource blocks originating from the control entity, including a value of a number of blocks allocated to the content server.