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TCP window full message after receiving ACK?


link textThe client's window size is 2836, the client requested http on frame 4. The server start sending data on frame 5, my question is on frame 8, why wireshark says TCP window full given the client already acked on frame 6? my understanding is that tcp window full only displays when the server send the amount of data equal to client's window size without getting an ack back, in my case, the ack was received on frame 6.

appreciate anyone provides some explanations. thanks.

asked 12 Dec '13, 09:18

czhang's gravatar image

accept rate: 0%

edited 12 Dec '13, 09:24

One Answer:


Well, you do not have packet sizes in your screenshot, but the ACK in frame 6 has a window size of 1488 bytes, which is most likely filled in packets 7 and 8. And since it is full in frame 8 Wireshark tells you so.

answered 12 Dec '13, 09:30

Jasper's gravatar image

Jasper ♦♦
accept rate: 18%

thanks Jasper. I appreciate it.

(12 Dec '13, 09:58) czhang

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(13 Dec '13, 01:38) grahamb ♦