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TCP header format

I am bad at memorizing things. So could anyone recommend me some mnemonics, so that I can remember the fields of the header...

Thank you.

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    $\begingroup$ Related -- Recall advice here that it's best to get away from relying on mnemonics: matheducators.stackexchange.com/questions/19289/… $\endgroup$ – Daniel R. Collins Jan 5 at 4:22
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    $\begingroup$ Aside from that: Do you have an instructor who actually said you need to memorize that packet format? That would be mind-boggling. $\endgroup$ – Daniel R. Collins Jan 5 at 4:24
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    $\begingroup$ Perhaps presenting some of the sample questions would be helpful for people to understand what the point is. $\endgroup$ – Daniel R. Collins Jan 5 at 6:29
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    $\begingroup$ Out of 54 questions on that site, I see only 2 that are possibly answered by memorizing the TCP header format. Question 29 would require this plus 3 other packet formats being memorized. Question 51 just requires recognizing some of the names here. I suggest that memorizing the packet format is not a good use of energy (as usual). $\endgroup$ – Daniel R. Collins Jan 5 at 7:57
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    $\begingroup$ @DanielR.Collins ok, once again thanks for the guidance... $\endgroup$ – Abhishek Ghosh Jan 5 at 8:30
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The first bit is where it is going. An intermediary needs this to forward it. It goes first so that at least in theory it can start forwarding before it has finished receiving. Next is the symmetrical data (where it is from). This is common to most protocols (ethernet mac-addresses, IP addresses, tcp/udp ports, …).

Next the two sequence numbers, in the same order as before: to (the sequence number of this segment), from (the sequence number of the last segment that I got from you).

Next the length of what remains, you need the length before you can start reading the rest (there is no other way to know where the the end is.

Then various flags, the window size and the rest.

Of this I only remember the first two (the two addresses). The rest I look up.

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