Conditional routing delivery in a compromised network

1 . A computer-implemented method for conditionally routing a data packet in a network node, the computer-implemented method comprising:

determining a level of deterioration of a primary path between the network node and a destination node, the determined level of deterioration based at least on a non-congestion-related loss for a primary link associated with one or more subsequent hops of the data packet from the network node towards the destination node along the primary path;

parsing the data packet to determine a threshold; and

comparing the determined level of deterioration of the primary path to the threshold, and based on the determined level of deterioration of the primary path being above the threshold:

changing the primary path to an alternate path from the network node to the destination node; and

forwarding the data packet to a next network node on the alternate path, wherein:

the data packet includes a conditional command specifying at least a condition and a command;

the condition specifying the threshold for the level of deterioration of the primary path; and

the command specifying the changing of the primary path to the alternate path when the determined level of deterioration of the primary path is above the threshold.

2 . The computer-implemented method of claim 1 , wherein:

the determining the level of deterioration of the primary path includes determining a non-congestion-related loss for a next link associated with a next hop of the one or more subsequent hops of the data packet along the primary path; and

the changing the primary path to the alternate path includes:

changing the next link in the primary path to a next link in the alternate path; and

forwarding the data packet to the next link in the alternate path.

3 . The computer-implemented method of claim 2 , wherein the next link associated with the next hop is directly coupled to the network node, and wherein:

the determining the level of deterioration of the primary path includes determining the non-congestion-related loss for a remote link along the primary path, the remote link being at least one hop away from the next link; and

the changing the primary path to the alternate path includes:

changing the next link in the primary path to a next link in the alternate path based on the non-congestion-related loss for the remote link; and

forwarding the data packet to the next link in the alternate path.

4 . The computer-implemented method of claim 3 , wherein the changing the next link in the primary path to the next link in the alternate path includes:

determining the non-congestion-related loss for the next link in the alternate path; and

changing the next link in the primary path to the next link in the alternate path when the next link in the alternate path exhibits less non-congestion-related loss than the next link in the primary path.

5 . The computer-implemented method of claim 4 , wherein the determining the non-congestion-related loss in the next link in the alternate path includes:

sending, by the network node, a probe packet to the destination node using the alternate path; and

determining a measure of non-congestion-related loss of the next link of the alternate path based on a response to the probe packet received from the destination node.

6 . The computer-implemented method of claim 5 , wherein the determining the non-congestion-related loss for the next link in the alternate path or the next link in the primary path includes determining a bit error rate (BER).

7 . The computer-implemented method of claim 1 , further comprising notifying a network controller of the non-congestion-related loss.

8 . The computer-implemented method of claim 7 , further comprising:

determining a measure of congestion-related loss for the primary path; and

notifying the network controller of the measure of the congestion-related loss.

9 . The computer-implemented method of claim 1 , wherein the changing the primary path to the alternate path further includes determining that a service requirement for the data packet indicates a performance level that is greater than a second threshold.

10 . The computer-implemented method of claim 1 , wherein the primary path is a traffic-engineered (TE) path conforming to at least one service level objective (SLO), and the alternate path is a pre-provisioned alternate TE path conforming to the SLO of the primary path.

11 . The computer-implemented method of claim 1 , wherein the primary path is a best-effort (BE) path, and the alternate path is a loop-free alternative (LFA) path, remote loop-free alternative (RLFA) path, or an Internet protocol fast reroute (IP FRR) path.

12 . The computer-implemented method of claim 1 , wherein the changing the primary path to the alternate path is based on execution of the command.

13 . A system for conditionally routing a data packet in a network node, the system comprising:

a memory storing instructions; and

at least one processor in communication with the memory, the at least one processor configured, upon execution of the instructions, to perform the following steps:

determining a level of deterioration of a primary path between the network node and a destination node, the determined level of deterioration based at least on a non-congestion-related loss for a primary link associated with one or more subsequent hops of the data packet from the network node towards the destination node along the primary path;

parsing the data packet to determine a threshold; and

comparing the determined level of deterioration of the primary path to the threshold, and based on the determined level of deterioration of the primary path being above the threshold:

changing the primary path to an alternate path from the network node to the destination node; and

forwarding the data packet to a next network node on the alternate path, wherein:

the data packet includes a conditional command specifying at least a condition and a command;

the condition specifying the threshold for the level of deterioration of the primary path; and

the command specifying the changing of the primary path to the alternate path when the determined level of deterioration of the primary path is above the threshold.

14 . The system of claim 13 , wherein:

the determining the level of deterioration of the primary path includes determining a non-congestion-related loss for a next link associated with a next hop of the one or more subsequent hops of the data packet along the primary path; and

the changing the primary path to the alternate path includes:

changing the next link in the primary path to a next link in the alternate path; and

forwarding the data packet to the next link in the alternate path.

15 . The system of claim 14 , wherein the next link associated with the next hop is directly coupled to the network node and wherein:

the determining the level of deterioration of the primary path includes determining the non-congestion-related loss for a remote link along the primary path, the remote link being at least one hop away from the next link; and

the changing the primary path to the alternate path includes:

changing the next link in the primary path to a next link in the alternate path based on the non-congestion-related loss for the remote link; and

forwarding the data packet to the next link in the alternate path.

16 . The system of claim 15 , wherein:

the changing the next link in the primary path to the next link in the alternate path includes:

determining the non-congestion-related loss for the next link in the alternate path; and

changing the next link in the primary path to the next link in the alternate path when the next link in the alternate path exhibits less non-congestion-related loss than the next link in the primary path; and

the determining the non-congestion-related loss in the next link in the alternate path includes:

sending, by the network node, a probe packet to the destination node using the alternate path; and

determining a measure of non-congestion-related loss of the next link of the alternate path based on a response to the probe packet received from the destination node.

17 . A non-transitory computer-readable media storing computer instructions for conditionally routing a data packet in a network node, that configure at least one processor, upon execution of the instructions, to perform the following steps:

determining a level of deterioration of a primary path between the network node and a destination node, the determined level of deterioration based at least on a non-congestion-related loss for a primary link associated with one or more subsequent hops of the data packet from the network node towards the destination node along the primary path;

parsing the data packet to determine a threshold; and

comparing the determined level of deterioration of the primary path to the threshold, and based on the determined level of deterioration of the primary path being above the threshold:

changing the primary path to an alternate path from the network node to the destination node; and

forwarding the data packet to a next network node on the alternate path, wherein:

the data packet includes a conditional command specifying at least a condition and a command;

the condition specifying the threshold for the level of deterioration of the primary path; and

the command specifying the changing of the primary path to the alternate path when the determined level of deterioration of the primary path is above the threshold.

18 . The non-transitory computer-readable media of claim 17 , wherein:

the determining the level of deterioration of the primary path includes determining a non-congestion-related loss for a next link associated with a next hop of the one or more subsequent hops of the data packet along the primary path; and

the changing the primary path to the alternate path includes:

changing the next link in the primary path to a next link in the alternate path; and

forwarding the data packet to the next link in the alternate path.

19 . The non-transitory computer-readable media of claim 18 , wherein the next link associated with the next hop is directly coupled to the network node, and wherein:

the determining the level of deterioration of the primary path includes determining the non-congestion-related loss for a remote link along the primary path, the remote link being at least one hop away from the next link;

the changing the primary path to the alternate path includes:

changing the next link in the primary path to a next link in the alternate path based on the non-congestion-related loss for the remote link; and

forwarding the data packet to the next link in the alternate path; and

the changing of the next link in the primary path to the next link in the alternate path includes:

determining non-congestion-related loss for the next link in the alternate path; and

changing the next link in the primary path to the next link in the alternate path when the next link in the alternate path exhibits less non-congestion-related loss than the next link in the primary path.