A method for determining differential delay of at least two bonded links is described. The method comprises a step of providing, on the part of a transmitting entity, at least some of the data packets transmitted from the transmitting entity to a receiving entity with time stamps, the time stamps indicating a point of time when a respective data packet has been generated, and a step of deriving a propagation delay from a time stamp of a data packet and a time of arrival of the data packet at a receiving entity. The method further comprises a step of determining a differential delay of a link from the propagation delay of the link and a propagation delay of a reference link.