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Hey guys,

I have a basic question which I'm stucked....

Im trying to use the TSecr (tcp.options.timestamp.tsecr) in order to help me calculate RTT since its stores time info from the sending server...

I just dont have any clue how to transform the values of Tsecr into time information in order to calculate the RTT. As far as I understood RTT would be RTT = Actual Time (for ACK) - TSecr but since it seems that TSecr is a field of 32 bits I have no clue how to transform it into time reference in order to help into RTT calculations.

Kind Regards Bruno

asked 17 Jul '12, 00:39

bmaia18's gravatar image

accept rate: 0%

The value of the TSecr field are in 'ticks' where the advise is to use a value between 1ms and 1s for each tick. But each system uses it's own tick value. So in order to use the TSecr value to calulate a time difference, you must first calculate the tick value for the specific host.

See RFC 1323 paragraph 4.2.2

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answered 17 Jul '12, 01:26

SYN-bit's gravatar image

SYN-bit ♦♦
accept rate: 20%

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question asked: 17 Jul '12, 00:39

question was seen: 6,068 times

last updated: 17 Jul '12, 01:26

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