TCP RST+data!

Mike Silbersack silby at
Mon Nov 26 07:43:15 PST 2007

On Mon, 26 Nov 2007, Ian FREISLICH wrote:

> Yet, a colleague managed to configure the phone using his Mac over
> that very slow link - analog leased line at 28.8kbps.  I do
> occasionally see resets even when not using delayed ack.

Hrm.  Maybe the phone determines the RTT based on how quickly the SYN-ACK 
was acknowledged, then drops the connection after 2xRTT?  Sounds crazy, 
but it would be no more crazy than the rest of the phone's TCP stack. :)

> I'm in communication with the vendor, so hopefully this will get
> fixed.  Interestingly, this is one of the few phones that I've been
> able to interact with web and telnet while it's busy on a call.
> Guess you win some... and loose some.
> Thanks for confirming my suspicions.
> Ian

Ah, good.  I hope that you are able to convince them to improve the phone; 
it sounds like it should not be that difficult for them to fix the 
RST-related issues.  The lack of sliding window is just a performance 
issue, so they can live without that.


More information about the freebsd-current mailing list