Routing method reducing the consequences of microloops
View Patent ↗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, comprising:
reading a field, called lifetime field of a received packet, intended to be decremented when passing through a 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 augmented if the lifetime field packet 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:
obtain link information on an output interface of the router for a received packet;
obtain lifetime field information from the packet;
determine if the link information is a tunnel whose destination is not a router directly neighboring the router;
augment a predetermined value called the decrementation pitch when the link is determined to be a tunnel;
decrement a value of the lifetime field by the decrementation pitch when passing through the router; and
wherein the program instructions are configured to destroy the packet when said value of the lifetime field is less than or equal to zero.
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).
9. A router system designed to route packets within a communications network in non-connected mode comprising a processor; and a memory storing program instructions executable by the processor to:
obtain link information on an output interface of the router system for a received packet;
obtain lifetime field information from the packet;
determine if the link information is a tunnel whose destination is not a router directly neighboring the router system;
augment a predetermined value called the decrementation pitch when the link is determined to be a tunnel;
decrement a value of the lifetime field by the decrementation pitch when passing through the router system; and
wherein the program instructions are configured to destroy the packet when said lifetime field value is less than or equal to zero.
10. The router system of claim 9 , wherein the program instructions are further executable to determine the output interface communications protocol is Fast Reroute (FRR).
11. The router system of claim 9 , wherein the program instructions are further executable to determine the output interface communications protocol is Virtual Private Network (VPN) MPLS.
12. The router system of claim 9 , wherein the program instructions are further executable to determine the output interface communications protocol is Interior Gateway Protocol (IGP).