The invention concerns a method of controlling the synchronization in a data packet communication network (10) having at least two serial communication buses (D, E) interconnected by a bridge (PDE) and each defining successive time cycles each having a duration specific to the said bus under consideration, the said method having the following steps: detection (C3, C4) of a relative drift between the respective cycles of the said at least two serial communication buses, transmission (C10, C12; C18, C17) of a command for modifying the duration of the cycle of one of the said at least two serial communication buses, characterised in that the said method includes at least one delay phase (C6, C7; C2, D1, D2) before at least one of the preceding steps.