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The question is that my application does not send ACK packet after receiving SYN,ACK response from server. I've managed to get dump when using different connection, but i could not find any critical differences between request-responses, which would result in such an issue.


Here is short version for "wrong" session, initiated by client:

[SYN] Seq=0 Win=65535 Len=0 MSS=1460 SACK_PERM=1 TSval=17625416 TSecr=0 WS=64

[SYN, ACK] Seq=0 Ack=1 Win=65535 Len=0 MSS=1440 SACK_PERM=1 WS=256

[SYN] Seq=0 Win=65535 Len=0 MSS=1460 SACK_PERM=1 TSval=17625720 TSecr=0 WS=64

[SYN, ACK] Seq=0 Ack=1 Win=65535 Len=0 MSS=1440 SACK_PERM=1 WS=256

[SYN, ACK] Seq=0 Ack=1 Win=65535 Len=0 MSS=1440 SACK_PERM=1 WS=256

[SYN] Seq=0 Win=65535 Len=0 MSS=1460 SACK_PERM=1 TSval=17626322 TSecr=0 WS=64

[SYN, ACK] Seq=0 Ack=1 Win=65535 Len=0 MSS=1440 SACK_PERM=1 WS=256

[SYN, ACK] Seq=0 Ack=1 Win=65535 Len=0 MSS=1440 SACK_PERM=1 WS=256

[SYN] Seq=0 Win=65535 Len=0 MSS=1460 SACK_PERM=1 TSval=17627524 TSecr=0 WS=64

[SYN, ACK] Seq=0 Ack=1 Win=65535 Len=0 MSS=1440 SACK_PERM=1 WS=256

[SYN, ACK] Seq=0 Ack=1 Win=65535 Len=0 MSS=1440 SACK_PERM=1 WS=256

here is short version for correct session:

[SYN] Seq=0 Win=65535 Len=0 MSS=1460 SACK_PERM=1 TSval=76086 TSecr=0 WS=64

[SYN, ACK] Seq=0 Ack=1 Win=65535 Len=0 MSS=1380 SACK_PERM=1 WS=256

[ACK] Seq=1 Ack=1 Win=65536 Len=0

[PSH, ACK] Seq=1 Ack=1 Win=65536 Len=259[Packet size limited during capture]

[ACK] Seq=1 Ack=260 Win=16128 Len=0

I'm totaly stuck here - i can find any evidence for what could happen with client-side.

share|improve this question
    
welcome, could you please provide provide more details? It's hard to understand the problem without context – user130370 Dec 28 '12 at 10:25
    
Well the situation is: I have an android application for podcasts. Sometime it gets stuck while downloading podcast list. Since i have some network-related software on my phone - I suspect, that it might cause some malfunction. The issue occurs only over wifi connection - when using 3G i face no problems. This makes me think, that it is some network-related issue, however, i have no evidence for that. – user151065 Dec 28 '12 at 10:36

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