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

From: Steve Bertrand <steve@xxxxxxxxxx>
Date: Wed, 25 Jun 2008 13:01:25 -0400
Frank Bulk wrote:
What do you suspect is setting the "do not frag bit"?  I'd be interested if
the customer's PC(s) are doing that, their attached router, or something
between their router and the switch in your office.

I'll have to find this out. If it is CPE router, it's only setting the flag when it comes across the fibre, and not the ADSL.

If it is their workstations, I would suspect that they would see the same result (or 'not' see a result in this case) on either connection.

My manual request for global.css also had the don't frag bit set, but I received the data anyway, in two 1434 byte segments.

If a PMTU discovery of 1500 bytes is attainable from other locations on the 'net, then I'll have to figure if it's one of our transits.

Steve