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I have captured two wireshark file captures through wireless and wired connections from same source desktop to a destination file server. Wireless capture works fine and download time is within 20seconds. Same file while downloading from wired connections i am getting below errors. TCP ACKEDunseen segment TCP Dup ACK 852#1

Above errors are receiving multiple times from destination server and not able to get the issue. The duplex settings are correct on both wired and wireless connetcions (full duplex 1000M)

Can you please help to understand the exact issue?

asked 03 May '17, 09:01

gokulkurunthasalam's gravatar image

accept rate: 0%

"TCP ACKed unseen segment" is not an error in your environment, it means that Wireshark has seen an acknowledgement packet for TCP data that it didn't see. So a data packet was sent and acknowledged, but Wireshark only saw the acknowledgement - this means that your capture PC was too slow to capture the data as well.

Dup ACKs happen every once in a while, usually for packet loss - but they're not always bad. Sometimes you see them for out-of-order arrivals. So I wouldn't worry about the expert messages you see, they're probably harmless.

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answered 03 May '17, 09:20

Jasper's gravatar image

Jasper ♦♦
accept rate: 18%

Thank you. I have attached the wireshark captured file fom source system. can you please analyze the issue and advise me? Destination - please give me url to attach the file

(03 May '17, 09:27) gokulkurunth...

You can share a capture in a publicly accessible spot, e.g. CloudShark, Google Drive, DropBox etc.

(03 May '17, 10:07) grahamb ♦
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question asked: 03 May '17, 09:01

question was seen: 1,771 times

last updated: 03 May '17, 10:07

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