Using TCP Acks to measure latency to a server?

Posted by Ted Graham on Stack Overflow See other posts from Stack Overflow or by Ted Graham
Published on 2010-05-05T15:18:38Z Indexed on 2010/05/06 3:08 UTC
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tcp

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latency

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Performance

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low-latency

I am trying to measure latency to a server that I don't control. This is in a colocated environment, so the latency is on the order of 500 us (.5 ms).

I understand that Cisco gear frequently deprioritizes ICMP traffic, making ping times unreliable. Is there a way for me to tell if this is the case on the gear I am traversing?

Can I use TCP acknowledgements to determine the minimum latency to the remote server? To do this, I would somehow need to force the remote server to send a TCP ack immediately on receiving my data.

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