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Interesting measurement, thanks for the time you put into it. I'm confused however, about this part : == The expected value for the TTL of queries is 333. However, since multiple probes can use the same resolver, we can expect some TTLs to be slightly smaller than 333. However, no queries should have a TTL above 333. == I thought each probe queried its own, individual RR ? If that is so, surely no probe should see a value of 320 <= x <= 333 ?