Routing method reducing the consequences of microloops
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 (E 1 ) the packet; —reading (E 2 ) a field, called the longevity field of the packet, intended to be decremented when traversing a router; —decrementing (E 5 ) the value of the longevity field using a step of a predefined value, called the decrementation step; —deciding (E 6 ) on the routing of the packet on the basis of the value of the decremented longevity field, the packet being destroyed (E 7 ) when said value is less than or equal to zero; the method further comprising, prior to the step of decrementing, the following steps: —obtaining (E 3 ) 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 (E 4 ) the value of the decrementation step on the basis of at least the obtained information.
1. A method for routing a packet within a packet switching network in non-connected routing mode, implemented by a router over a first link associated with an input interface and a second link associated with an output interface, comprising
reading a field, called lifetime field of a received packet, from the first link associated with the input interface, intended to be decremented when passing through the router;
decrementing the value of the lifetime field packet by a pitch of predetermined value, called decrementation pitch;
decision on routing of the packet depending on the value of the decremented lifetime field packet, the packet being destroyed when said value is less than or equal to zero;
the method being characterized in that it furthermore comprises, prior to the decrementation step, the following steps:
obtaining lifetime field packet of the router for the packet;
determining that the value of the pitch is not decremented of the lifetime field packet if the second link associated with the output interface is a tunnel whose destination is not a router directly neighboring the router.
2. A non-transitory computer readable storage medium comprising program instructions executable-by a router-to:
read a field, called lifetime field of a received packet, from a first link associated with an input interface, intended to be decremented when passing through a router;
decrement the value of the lifetime field packet by a pitch of predetermined value, called decrementation pitch;
deicide on routing of the packet depending on the value of the decremented lifetime field packet, the packet being destroyed when said value is less than or equal to zero;
the method being characterized in that it furthermore comprises, prior to the decrementation step, the following steps:
obtain lifetime field packet of the router for the packet;
determine that the value of the pitch is not decremented of the lifetime field packet if a second link associated with an output interface is a tunnel whose destination is not a router directly neighboring.
3. The non-transitory computer readable storage medium of claim 2 , wherein the program instructions are further executable to determine the output interface communications protocol is Fast Reroute (FRR).
4. The non-transitory computer readable storage medium of claim 2 , wherein the program instructions are further executable to determine the output interface communications protocol is Virtual Private Network (VPN) MPLS.
5. The non-transitory computer readable storage medium of claim 2 , wherein the program instructions are further executable to determine the output interface communications protocol is Interior Gateway Protocol (IGP).
6. The method for routing a packet as claimed in claim 1 , wherein, the output interface communications protocol is determined to be Fast Reroute (FRR).
7. The method for routing a packet as claimed in claim 1 , wherein, the output interface communications protocol is determined to be a Virtual Private Network (VPN) MPLS.
8. The method for routing a packet as claimed in claim 1 , wherein, the output interface communications protocol is determined to be Interior Gateway Protocol (IGP).