Micro-loop prevention using source packet routing
First Claim
1. A method comprising:
- detecting, by a near-side point of local failure (NPLR), a failure of a communication link that couples the NPLR and a far-side point of local failure (FPLR), wherein the NPLR and the FPLR are each network devices that implement a Source Packet Routing in Networking (SPRING) protocol to forward network packets using node labels according to an initial network topology of a network that comprises a plurality of other network devices, wherein the NPLR, the FPLR, and any of the other network devices operating in accordance with the SPRING protocol exchange the node labels using at least one link-state interior gateway protocol (IGP);
responsive to detecting the failure of the communication link, applying, by the NPLR and for a defined time duration, one or more adjacency labels in accordance with the SPRING protocol to network packets destined for a destination network device, wherein the one or more adjacency labels define a set of one-hop tunnels corresponding to a backup sub-path that circumvents the failed communication link;
forwarding, by the NPLR and according to a temporary network topology that is based on the set of one-hop tunnels that provide the backup sub-path, the network packets; and
upon expiration of the defined time duration, forwarding, by the NPLR and according to a new network topology that is not based on applying the one or more adjacency labels that define the set of one-hop tunnels, network packets destined for the destination network device.
1 Assignment
0 Petitions
Accused Products
Abstract
In general, techniques are described for reducing or otherwise preventing micro-loops in network using Source Packet Routing in Networking (SPRING). In some examples, a method includes detecting a failure of a communication by a network device that implements a Source Packet Routing in Networking (SPRING) protocol to forward network packets using node labels according to an initial network topology. Responsive to detecting the failure of the communication link, the network device may apply, for a defined time duration, one or more adjacency labels to network packets to define a set of one-hop tunnels corresponding to a backup sub-path that circumvents the failed communication link. Upon expiration of the defined time duration, the network device may forward, according to a new network topology that is not based on applying the one or more adjacency labels that define the set of one-hop tunnels, network packets destined for the destination network device.
102 Citations
20 Claims
-
1. A method comprising:
-
detecting, by a near-side point of local failure (NPLR), a failure of a communication link that couples the NPLR and a far-side point of local failure (FPLR), wherein the NPLR and the FPLR are each network devices that implement a Source Packet Routing in Networking (SPRING) protocol to forward network packets using node labels according to an initial network topology of a network that comprises a plurality of other network devices, wherein the NPLR, the FPLR, and any of the other network devices operating in accordance with the SPRING protocol exchange the node labels using at least one link-state interior gateway protocol (IGP); responsive to detecting the failure of the communication link, applying, by the NPLR and for a defined time duration, one or more adjacency labels in accordance with the SPRING protocol to network packets destined for a destination network device, wherein the one or more adjacency labels define a set of one-hop tunnels corresponding to a backup sub-path that circumvents the failed communication link; forwarding, by the NPLR and according to a temporary network topology that is based on the set of one-hop tunnels that provide the backup sub-path, the network packets; and upon expiration of the defined time duration, forwarding, by the NPLR and according to a new network topology that is not based on applying the one or more adjacency labels that define the set of one-hop tunnels, network packets destined for the destination network device. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. A network device, wherein the network device is a first point of local failure (PLR), the network device comprising:
-
at least one processor; at least one module operable by the at least one processor to; detect a failure of a communication link that couples the first PLR and a second PLR, wherein the first PLR and the second PLR are each network devices that implement a Source Packet Routing in Networking (SPRING) protocol to forward network packets using node labels according to an initial network topology of a network that comprises a plurality of other network devices, wherein the first PLR, the second PLR, and any of the other network devices operating in accordance with the SPRING protocol exchange the node labels using at least one link-state interior gateway protocol (IGP); responsive to detecting the failure of the communication link, apply, for a defined time duration, one or more adjacency labels in accordance with the SPRING protocol to network packets destined for a destination network device, wherein the one or more adjacency labels define a set of one-hop tunnels corresponding to a backup sub-path that circumvents the failed communication link; forward, according to a temporary network topology that is based on the set of one-hop tunnels that provide the backup sub-path, the network packets; and upon expiration of the defined time duration, forward, according to a new network topology that is not based on applying the one or more adjacency labels that define the set of one-hop tunnels, network packets destined for the destination network device. - View Dependent Claims (12, 13, 14, 15, 16)
-
-
17. A method comprising:
-
receiving, by a non-point of local failure (non-PLR) network device of a plurality of network devices in a segment routing domain, a link state advertisement that a communication link has failed between a near-side point of local failure (NPLR) and a far-side point of local failure (FPLR) that are each included in the segment routing domain, wherein the non-PLR, NPLR and the FPLR are each network devices that implement a Source Packet Routing in Networking (SPRING) protocol to forward network packets using node labels according to an initial network topology of a network that includes the plurality of network devices, wherein the non-PLR, the NPLR, the FPLR, and any of the other network devices operating in accordance with the SPRING protocol exchange the node labels using at least one link-state interior gateway protocol (IGP); responsive to receiving the link state advertisement, initiating, by the non-PLR network device, a timer; configuring, before the timer has expired, a forwarding state of the non-PLR network device, to forward network packets according to a new network topology; and forwarding, while the timer has not expired and by the non-PLR network device, network packets destined for a destination network device according to a temporary network topology that is different than the new network topology, wherein the temporary network topology is based on one or more adjacency labels in accordance with the SPRING protocol that define a set of one-hop tunnels corresponding to a backup sub-path that circumvents the failed communication link between the NPLR and the FPLR. - View Dependent Claims (18, 19)
-
-
20. A method comprising:
-
receiving, by a non-point of local failure (non-PLR) network device of a plurality of network devices in a segment routing domain, a link state advertisement that a communication link has failed between a near-side point of local failure (NPLR) and a far-side point of local failure (FPLR) that are each included in the segment routing domain, wherein the non-PLR, the NPLR and the FPLR are each network devices that implement a Source Packet Routing in Networking (SPRING) protocol to forward network packets using node labels according to an initial network topology of a network that includes the plurality of network devices, wherein the non-PLR, the NPLR, the FPLR, and any of the other network devices operating in accordance with the SPRING protocol exchange the node labels using at least one link-state interior gateway protocol (IGP); responsive to receiving the link state advertisement, initiating, by the non-PLR network device, a timer; configuring, before the timer has expired, a forwarding state of the non-PLR network device, to forward network packets according to a new network topology; forwarding, while the timer has not expired and by the non-PLR network device, network packets destined for a destination network device according to a temporary network topology that is different than the new network topology, wherein the temporary network topology is based on one or more adjacency labels in accordance with the SPRING protocol that define a set of one-hop tunnels corresponding to a backup sub-path that circumvents the failed communication link between the NPLR and the FPLR; and responsive to the expiration of the timer, forwarding, by the non-PLR network device, network packets destined for the destination network device according to the new network topology, wherein forwarding network packets destined for the destination network device according to the new network topology further comprises; applying to a first network packet destined for the destination network device, by the non-PLR network device, a first node label that is different than a second node label, wherein the second node label was applied to a second network packet based on the original network topology, wherein the second network packet was destined for the destination network device.
-
Specification