RE: Request for feedback on ip-nat

["Joris L." <jorislambrecht () pandora be>]

Op di 03-02-2004, om 21:33 schreef Shawn Jackson:
> > From: Joris L. [mailto:jorislambrecht () pandora be]
> > I'm currently investigating possible reasons for client-programs 
> > to a im network to disconnect for no real apparent reason. What 
> > could be the possible causes, what could cause a time-out to 
> > occur ? 
>
> Some 'cheap' NAT boxes will clear their connection cache, or at
> least the oldest connections, to conserve memory. I've noticed
> this on older Netgear and some linksys boxes at busy offices.

I'm using Linux with iptables. For my home-fw i have no issues with
this. I've even tried-out switching hardware because of possible
link-layer/framing issues but that doesn't seem to be an option.

> Additionally some real cheap boxes have a limitation to the
> actual number of NAT connections they can route. I don't
> know the detail of the MSN protocol, but it could be experience
> a timeout due to latency.

That's worth investigating, i'll check that.

> Does is die under use? Or while it's idle? Are you connecting
> to the I-Net or to another network? Are there any security
> policies in place on the NAT box? Is the NAT box a firewall?
> What model/type?

No, it is quite a performant box but there's indeed some issue wich is
pretty awkward to get hold of. The nat-box is set up for ip-masquerading
with the iptables firewall for policy, all is running on the same
machine.

> Shawn Jackson
> Systems Administrator
> Horizon USA
> 1190 Trademark Dr #107
> Reno NV 89521
>
> www.horizonusa.com
> Email: sjackson () horizonusa com
> Phone: (775) 858-2338
>              (800) 325-1199 x338

Thanks.

J.


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