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Wireshark-users: [Wireshark-users] TCP retransmit, HTTP and web page not loading

From: Steve Bertrand <steve@xxxxxxxxxx>
Date: Wed, 25 Jun 2008 09:19:46 -0400
Hi everyone. This is my first post here, so I hope I'm within context, and within any list charter with my post (which I could not find ;). By going through the archives, it appears as though I'm in the right place.

I'll get right to my point. I have a client whom I supply a 100Mbps Ethernet over fibre connection to, as well as an ADSL connection. One website in particular, www.tigerdirect.ca works fine over the ADSL connection.

The same computer connected via fibre can not view the site (well, not visually...).

I run tcpdump (saved to a Wireshark compatible output file) on my VLAN switch at my end prior to going to the client end over the fibre. I can see the communication from workstation to the site and vise-versa, and it *appears* as though all is well.

The only difference between what I see on ADSL and fibre is the numerous 'TCP Retransmission' errors for one particular GET command on the fibre. I have two questions (I am not hugely familiar in the frame level aspects of network communication. I am more in the business of routing the packets).

There is a screen cap of the final communication between the server and client if anyone could possibly have a look if they can answer my questions.

http://ibctech.ca/screencap/fibre_communication.jpg

A) Will a TCP session finish successfully even if some frames could not be ultimately received?

B) From what I have in the screencap without the frames expanded, is it safe to assume that the file mentioned in the retransmission message did not get transferred?

Symptoms are the Title of the site appears in the browser, it spins it's wheels, then stops.

Thanks for any guidance,

Steve