[Freeciv-Dev] Re: Network bandwidth, and other things.

[Christian Knoke <chrisk@xxxxxxxx>]

On Wed, Nov 06, 2002 at 03:39:38PM -0500, Jason Dorje Short wrote:
> Christian Knoke wrote:
> >On Wed, Nov 06, 2002 at 02:40:40PM -0500, Jason Dorje Short wrote:
> >
> >>Christian Knoke wrote:
> >>
> >>
> >>>What happens with TCP/IP, when a single packet got lost? I think, in the
> >>>first place, _nothing_ happens. Neither of both endpoints of the 
> >>>connection
> >>>gets aware of this (But I may be wrong here!). Only after another packet 
> >>>is
> >>>sent in the same direction, or a specific amount of time passes, the
> >>>receiver gets notified of this and resends the packet.
> >>
> >>After each packet sent an "ACK" packet is sent in return.  If the ACK 
> >>does not arrive in a reasonable timeframe (which is a very difficult 
> >>subject in itself), the packet is resent.
> >
> >
> >Yes, that's the question! If the timeframe is 10 sec or greater, the above
> >applies.
> >
> >
> >>So, this is not a problem.
> >
> >
> >Not?
> 
> Right, not.

[...]

Thank you for your explanation, it enlightens me much :-)

> The conclusion is: TCP performance is really awful over a high-latency 
> connection.  It is also really awful when any significant portion (even 
> just 1%) of packets get dropped.  And by resending packets, it is likely 
> to congest the network even more causing the drop rate to increase.

Just thinking what happens if we change to UDP ... :)

> jason

Christian

-- 
Christian Knoke     * * *      http://www.enter.de/~c.knoke/
* * * * * * * * *  Ceterum censeo Microsoft esse dividendum.