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TCP ACked Unseen Segment


Hi all,

I am getting the TCP ACKed Unseen segment. Could anyone explain the stats of these packets. Why is it like this? 760 10:11:22.438873 TCP 58 [TCP ACKed unseen segment] 42161→3200 [RST, ACK] Seq=322 Ack=2420 Win=0 Len=0 761 10:11:22.438878 TCP 58 [TCP ACKed unseen segment] 3200→42161 [RST, ACK] Seq=2420 Ack=322 Win=0 Len=0

asked 24 Sep '15, 23:38

rcrkollam's gravatar image

accept rate: 0%

edited 25 Sep '15, 02:37

grahamb's gravatar image

grahamb ♦

One Answer:


"TCP ACKed unseen segment" means that this packet acknowledges data that wasn't captured. It was transferred okay, and the receiver acknowledges it, but Wireshark can't find the packet in the capture. This usually happens when the capture device wasn't fast enough.

answered 25 Sep '15, 02:16

Jasper's gravatar image

Jasper ♦♦
accept rate: 18%