Question about Window Scaling

[J65nko]

On 8/30/07, Shah, Baiju-p98993 <Baiju.Shah at gdc4s.com> wrote:
> Greetings.
>
> We currently use Espion appliance running FreeBSD 4.9 as a mail interceptor for SPAM.  We have one customer who has their mail gateway hard coded with Window Scaling (WS=9).  Their mail gateway fails to establish SMTP hello connection with WS=9.  However if they set their Window Scaling to 7, it works.
>
> Where can I go on the FreeBSD to see its configuration for Window Scale?  How can I modify that configuration?  Please email me with your recommendation to baiju.shah at gdc4s.com. Any and all help are appreciated.  Thank you in advance.
>
[snip]

A not well configured firewall also could cause problems with TCP
window scaling. See the section "Create TCP states on the initial SYN
packet" of
 Daniel Hartmeier's article at
http://undeadly.org/cgi?action=article&sid=20060928081238

=Adriaan=