The invention concerns a method for routing a packet in a packet switching network in disconnected routing mode, implemented by a router, comprising the following steps: —receiving (E1) the packet; —reading (E2) a field, called the longevity field of the packet, intended to be decremented when traversing a router; —decrementing (E5) the value of the longevity field using a step of a predefined value, called the decrementation step; —deciding (E6) on the routing of the packet on the basis of the value of the decremented longevity field, the packet being destroyed (E7) when said value is less than or equal to zero; the method further comprising, prior to the step of decrementing, the following steps: —obtaining (E3) at least one item of information from a group of items of information comprising an item of information relative to routing conditions of the packet and an item of information relative to parameters of the packet; —determining (E4) the value of the decrementation step on the basis of at least the obtained information.