UDP for pixel data transmission

[Celine Fages]

Will, thanks for the answer !

Will Dean a =E9crit :

> The most significant advantage of UDP over TCP is that you don't have t=
o go
> through a performance to establish a connection each time you want to s=
end
> data.  VNC doesn't break and re-establish a TCP stream each time it sen=
ds a
> rectangle, so there wouldn't be a create deal saved.  It opens a socket
> when you connect a client and then disconnects it when you disconnect.
>

I agree with this but could the control (by sending ack) that TCP makes f=
or
each sent packet, have a significant influence on performance (when these
packets are very numerous) ? this in comparison with UDP which doesn't ma=
ke
this control ?

>
> The main disadvantage of UDP is that packets can go missing without any=
one
> knowing - this might not matter for VNC mouse updates, but would, in
> general, be unacceptable.  (Try considering a text editor where some of=
 the
> characters were updated and some weren't.)
>

yes, I forget this... So, we could use UDP only for applications which ha=
ve a
lot of updates and can accept to lose some data ?

>
> Myself, I can't see much mileage in it, but I might have missed somethi=
ng.
>
> Cheers,
>
> Will
>
> --
> Will Dean - Industrial Computing Ltd
> Cambridge, UK

thanks again
c=E9line
--
C=E9line FAGES
SILOGIC
http://www.silogic.fr
78 chemin des 7 deniers
31200 TOULOUSE
FRANCE



---------------------------------------------------------------------
To unsubscribe, send a message with the line: unsubscribe vnc-list
to majordomo "at" uk.research.att.com
See also: http://www.uk.research.att.com/vnc/intouch.html
---------------------------------------------------------------------