DSL problems and compression

Frank Evan Perdicaro frank "at" dsea.com
Wed, 02 Jan 2002 23:47:44 +0000


> Subject: DSL system and no screen update
> Jeff,
> 
> > The modem connection worked and continues to work. The DSL connection
> > refuses to work. We can ping all available machines, have put a
> > sniffer on the server and verified that viewer packets are being sent
> > and received. However whenever we connect we enter the password, with
> > no error, the initial grey screen comes up, displays "initial screen
> > loading" and just sits there. The connection is eventually closed
> 
> I'm not saying this is the fix, but it sounds like you've got a funny MTU size set 
> on the DSL router.

Although I do not have the exact reference handy, some rather famous
high-speed-at-home hardware has bugs.  Perhaps 6 weeks ago I read
Steven Hanes column in Forbes on buggy network hardware.  Yeah, that is
the same guy with the television show.  Only one of his tools -- a
remote backup program -- excercised the hardware enough to find the
problem.  A search at Forbes.com should find the reference.  Nasty,
hard-to-find problem.

Naturally the hardware vendor did a good Clinton act -- deny, deny,
deny, obfuscate and delay.


> Subject: Re: Windows layer storage/transmission.
> 
> On Wed, 2002-01-02 at 03:55, A friend wrote:
> > Why not, for the server, for the client it's no problem for sure. Is it not
> > possible to capture the image from within a single window within MS-Windows?
> > I think it is, since Alt-PrintScreen does the same thing. Monitoring window
> > creation/deletion must be possible too.
> 
> Hmmm, yes, I didn't think of that. However, wouldn't a global pixmap
> cache solve the same problem in a more general way? For example, the
> server would scan the screen for patterns that tend to repeat, and then
> send them to the client only once, thereafter sending only a reference
> number. Things like font characters, window borders, buttons, icons,
> etc. could then all be saved at the client, and the server would only
> send their arrangement.

Keep running down that road and you will end up next door to me.  While
you are caching things, change the color space of the LRU items to BW,
and lower the resolution.

Has anybody else noticed the close parallels of this approach to "Part
1: Discrete Noiseless Systems" of Shannon's "A Mathematical Theory of
Communications" (1948)?

Yes, what is proposed above will work!
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