On Monday, February 24 2003, "Jiri Kuthan" wrote to "[EMAIL PROTECTED], [EMAIL 
PROTECTED], [EMAIL PROTECTED]" saying:

> On Fri, 21 Feb 2003 [EMAIL PROTECTED] wrote:
> 
> > I have always assumed that even if a proxy is used as an outbound 
> > proxy, an ACK (or any request within a dialog for that matter) does not
> > get sent to that outbound proxy unless the outbound proxy has
> > record-routed.
> 
> That's not the case always. Many phones keep sending ACK to outbound 
> proxy.
> 
> > Having said that, I would expect that a stray ACK arriving at a proxy
> > would just be dropped since it arrived there by accident. I also think
> > that this might be implementation specific. 
> 
> That would cause the INVITE transaction to never complete in the case 
> I mention.

So what do you recommend for the stray-ACK problem?

I was wrong to say that ACK proxying is non-amplifying -- forwarding an ACK
can cause a single UDP packet to trigger a DNS lookup and a TCP or TLS
connection attempt.

-- 
Jonathan Lennox
[EMAIL PROTECTED]
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