[4.9-R]Can I Make My DSL Connect Go Faster ? (OSX nat hint)

[Darcy Buskermolen]

On May 4, 2004 11:50 am, Chuck Swiger wrote:
> The Jetman wrote:
> [ ... ]
>
> >     Wes:  I've used a couple of Internet speed tests, at different times,
> > but always w/ the same configs.  Neither config has been modified.  All
> > of the results are the same.  I use ADSLGuide and DLSReports as my speed
> > tests, which are in different continents, but both report the same
> > speeds.  I use different browsers, but Java is what does the deal.
>
> If you're using a DSL provider like Verizon which uses PPPoE, you might try
> adjusting your MTU down to 1490 or so, or else you will fragment large data
> packets and encounter quite a slowdown.
>
> Use something like this in your /etc/rc.conf file:
>
> ifconfig_fxp0="inet 192.168.1.2 netmask 255.255.255.0 mtu 1490"
>
> ...or run ifconfig directly and see whether this helps.

On this exact note (and for sake of saveing hours for someone else...) , I 
recently turned a Macintosh G3  box running OSX 10.3 into a firewall/nat box 
without using their brain dead "internet shareing" tool.  What I found was 
their natd sucked wind unless you had the apple vender extention of 
"clamp_mss yes" in your natd.conf

From the natd man page:
     -clamp_mss
                 This option enables MSS clamping.  The MSS value is derived
                 from the MTU of the interface specified in the -interface
                 option.

I know this option isn't valid in FreeBSD's natd and I'm not sure if perhaps 
it is handleded transparently.  But with out this option under OSX I saw 
simular problems as to what you are describing when natting packets, even 
though the same download form the gateway were AOK

(Perhaps soemone a bit more versed on the internals of nat can comment on this 
under FreeBSD)
--
Darcy Buskermolen
Wavefire Technologies Corp.
ph: 250.717.0200
fx:  250.763.1759
http://www.wavefire.com