Hi, I would like to provide feedback on this informational draft.
*Background: * When an operator is building a network a careful planning and consideration is given to size links according to anywhere from 60%-80% of expected traffic patterns/demands. So when congestion occurs it is usually reason of either: A) topology change (already single failure active in the network) or B) traffic demand (hopefully transiently) exceeded the expectations. *Observation: * If congestion is triggered by B) usually already path from ingress to egress will expect congestion on egress interfaces. If this is A) then the number of nodes experiencing congestion of active paths depends on the location of the failure in the topology. *Proposed action:* The proposal is suggesting that each node acting autonomously should enable in a FRR fashion at PLRs a bypass of congested link. I think practically this can lead to complete network meltdown for number of reasons: - End to end protocols will need to adjust to new transit times - Bypass paths maybe already saturated with traffic causing even further traffic oscillations - It ruins operators intended end to end TE (if in place) which can potentially result in skipping some of the expected actions to be done on packets in certain nodes *Conclusion: * Do not do it. Possible risks exceed the potential gains. Kind regards, Robert. PS. Section 3.1 is written purely theoretical. Practical networks use QoS and there is usually a number of queues with different treatment applied to various traffic packets. Take as an example congestion of the best effort queue does not mean anything serious ... It is best effort after all. It can be safely dropped.
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