[cluda01]

I'm not sure if this is possible. According to Wolfram Alpha the distance between NYC and Tokyo is ~10879 Kilometers (as the crow flies, not as the cable lies). The speed of light in Kilometers per second is 299,792.458

If we evaluate (10879 / 299792.458) * 1000 = 36.28. This is for a single leg. So we get 72.57 milliseconds just for as the crow flies transport. This does not include other factors that contribute to latency (network, processing, etc.)

For "round trip" as you say then this number should be multiplied by 2 as it has to go NYC -> Tokyo, Tokyo -> NYC.

Have you developed some sort of faster than the speed of light communication mechanism we haven't heard of? Inquiring minds demand to know.

Edit: One possible explanation is that you are using multiple time sources that are not synchronized. E.g. if you send a FIX message to an ECN and use the clock available on your machine and then use the ECN's timestamps somewhere in your calculation this renders the measurement invalid because you can't ensure that your clocks are synchronized.