[jdev] tcp acknowledged sequence number

[Justin Karneges]

On Tuesday 12 October 2004 11:57 am, Alexey Nezhdanov wrote:
> В сообщении от Вторник 12 Октябрь 2004 22:17 Jacek Konieczny написал(a):
> > On Tue, Oct 12, 2004 at 09:31:46PM +0400, Alexey Nezhdanov wrote:
> > > When time out will be hit - connection will broke so I need to know
> > > wich packet was delivered last and wich were just dropped by tcp/ip
> > > stack to re-send them later when client come back online.
> >
> > You may always use one of the JEPs providing delivery notifications
> > (JEP-12 or JEP-79) provided the recipient client supports the extension.
>
> That's the main problem: lack of client support. I'm just trying to improve
> things with existing clients.
>
> > TCP ack doesn't mean the client read the data
> > from the socket buffer or its internall IO buffer.
>
> It's their problem. If data is delivered to client it is completely
> client's work to not loose it.
>
> And finally - didn't anybody else noticed these mail that I'm referring to
> - an example of socket call to extract "ack position" ?

I wrote about how to track the TCP outbound queue in Linux here:

https://www.jabber.org/standards-jig/2003-December/004570.html

However, I think it would be more preferrable if we had JEP-Ack, because not 
everyone has access to such information about their TCP/IP stack, and JEP-Ack 
also covers the proxy situation.

http://delta.affinix.com/specs/jep-ack.html

Don't worry, this is a very well known problem and I'm trying to push a 
solution for it.

-Justin