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1) if tcp syn request wants a 1576 byte "put/write" transfer, will it be sent along with syn request or must send data transfer wait until the syn recieves an ack?

2) does the answer change if the syn request needs a 1576 byte "get/read" transfer?

3) can tcp syn be rejected due to a syn window parameter that isnt supported by the other side?

4) can the response accept the syn but throttle the syn window value proposal?

asked 16 Oct '13, 01:46

rtrauben's gravatar image

rtrauben
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converted to question 16 Oct '13, 02:01

grahamb's gravatar image

grahamb ♦
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1 & 2) SYN is not a request containing data, it is a session setup signal. So in classic TCP you have to do the Three Way Handshake first before transmitting data requests. There are some TCP protocol modifications that aim at sending data with the SYN, but they're not widely used at the moment. Some also have risks regarding the security of the connection, like T/TCP.

3) No. Well, theoretically a node can always refuse a session by sending an RST, yes, but it doesn't happen in the real world - at least not because of the Window size.

4) No. Window size is per node, so each node decides what Window to advertise. The other node has no saying in how large it should be.

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answered 16 Oct '13, 02:36

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Jasper ♦♦
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There are some TCP protocol modifications that aim at sending data with the SYN, but they're not widely used at the moment.

is that part of an RFC?

(16 Oct '13, 03:05) Kurt Knochner ♦

Nice. Thanks!

(16 Oct '13, 13:37) Kurt Knochner ♦
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question asked: 16 Oct '13, 01:46

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last updated: 16 Oct '13, 13:37

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