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Wireshark-users: [Wireshark-users] Why does server resend SYN+ACK?

From: Andrej van der Zee <andrejvanderzee@xxxxxxxxx>
Date: Sun, 6 May 2012 14:00:48 +0900
Hi,

I am experiencing some weird behavior in the network traffic between a
mobile device and an Apache server 2.2 running on Linux (tried Ubuntu
and CentOS). See attachment for a packet capture on the server.

The client establishes a connection with the server in packet 1-3.
Then, for some unknown reason, the client does not send any HTTP
request. After 3 seconds, the server resends the SYN+ACK. I am trying
to understand what is going on here and why would TCP/IP resend the
SYN+ACK in packet 4?

Thanks,
Andrej

Attachment: NSURLConnection.png
Description: PNG image