headers-edge.txt mpls

[ytti]

I don't think you can reliably recognize protocol below MPLS (line 37..42)

You're now presuming reading BOS + IP version is reliable, but IANA assigns OUIs randomly since several years, so in many cases DMAC may look like IP version, causing misclassification in the naive approach. Potentially causing reordering as ECMP guarantees might not apply.

I wonder if there even is proper/cheap fix? Or do you just need to assume IP based on IP version, until IP checksum fails (ipv4) => presume it's eth, or IPv6 until L4 checksum fails? Which seems terribly expensive.