Would Fast Ethernet help?

Tristan Richardson tjr "at" orl.co.uk
Mon, 02 Mar 1998 20:17:05 +0000


> 
> I've modded the VNC client to show you a decaying average of bandwidth
> in the console window while the X program runs. The result is most
> interesting and shows that really VNC wants about 256kbits+ to be useful
> at the moment.

You need to be careful about how you test the bandwidth used by VNC.  The VNC
(RFB) protocol is quite good at adapting to the bandwidth you have available. 
If you have a busy desktop with lots of things changing and the bandwidth to
cope with it then VNC (or Xvnc at least) will update frequently.  But on a
slower link you'll see fewer updates, a bit like reducing the frame rate with
video.

How much bandwidth you need also depends a lot on what you're doing inside
your VNC desktop - and also how fast you expect it to be!  I've been
pleasantly surprised how many people have commented that VNC is totally usable
over a modem.

Having said all that, I think your estimate of 256kbits is in the right ball
park.  It's around the threshold where VNC starts to feel really usable and
you find yourself waiting for the remote applications to do their stuff rather
than simply waiting for the display to update.


Cheers

Tristan

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