Ability to detect swapped/merged LSPs

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>From the current base draft "If the Your Discriminator field is nonzero, it MUST be used to select the session with which this BFD packet is associated. If no session is found, the packet MUST be discarded."

If a node receives a BFD packet with a Discriminator field that it doesn't have a session for then there is a problem somewhere in the network, so why is the packet simply dropped and no further action taken?

If we get a swapped LSP (e.g. due to a corrupted forwarding table or configuration error) then all BFD packets received for the corresponding session will be dropped and the session will be declared down as a detection timeout will occur. However, if we get a merging defect where a node receives both valid BFD packets in addition to invalid BFD packets then this defect will not be detected.

In both cases, traffic is being forwarded onto the wrong destination and therefore these defects need to be detected and appropriate actions taken, e.g. raise an alarm and inform the LSP source (using the appropriate BFD status code) that a defect has occurred so that the source can stop forwarding packets or switch over to an alternative path if one exists.

I know that the idea behind the BFD draft is to keep it as simple as possible, but speaking as an operator, I would consider these defects to be just as important as loss of connectivity defects. They might not occur as frequently but are potentially more dangerous, e.g. I don't want to unknowingly be sending packets from customer As network to customer Bs network. 

By adding new processing rules and status codes, both of these defects could be detected using BFD. An alternative would be to use LSP ping but it would not provide the same defect detection speed, i.e. an LSP might only get tested using LSP pings every 30mins or maybe every hour in a large network with hundreds of thousands of PWs/LSPs, as opposed to BFD packets that can be sent every second.

Does anyone have any arguments for/against adding the ability to detect these defects into BFD?

Thanks,
Richard