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Given that the ISN of a packet of a TCP flow is 4290000000 and the sequence number of the FIN packet is 100000, how do i find the size of the total file?

asked 21 Apr '15, 19:30

Alicia%20Soh's gravatar image

Alicia Soh
accept rate: 0%

You don't, at least not reliably, because the sequence number is "only" 32 bits and you can't say for sure how often it wrapped during the file transfer. Also, there may be multiple files transferred in one TCP session, which again denies deduction of the file sizes.

It's usually better to use the high level protocol fields carrying the file size to determine it.

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answered 22 Apr '15, 02:07

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Jasper ♦♦
accept rate: 18%

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question asked: 21 Apr '15, 19:30

question was seen: 2,475 times

last updated: 22 Apr '15, 02:07

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