Re: Two computers in one: two users each with their own accounts, monitor, and keyboard?

[Albretch Mueller <lbrtchx@gmail.com>]

>>  The only extra cost here would be the special video cards for each

>> seat but even they are commercial nowadays and making multi-seat work

>> would be our job right?

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> You're still missing the overall picture here.  In your living room or basement, or in a library or lab with a 30 foot long desk, this concept may work, somewhat.

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 OK, lets go into the details and by the way I am a tech monkey myself
(more into soft than hardware) but when I think about matters I also
think about their business sense even if not in the details of it

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> ... you end up spending more on in wall cabling, baluns, wall plates, and other devices than if you put a complete PC in each room

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 Well, provided that computer was networked "wall cabling, baluns,
wall plates" were present already. The long shielded monitor cables we
are talking about would be thicker but that would be pretty much it. a
100 ft CAT5 cable on ebay

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 http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=170386214077

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 costs you $10. cablesdirect.com sales a 100 ft VGA cable for some $125

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 http://www.cablesdirect.com/pricewatch.asp?txtPartNo=CC320B-100&txtSellingPrice=104.369

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 yet you can find the same thing on ebay for less some $35

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 http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=330393097609

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 so the difference would be $25 and again I expect for them to become
much cheaper if such industries happen. Networking is already a mass
market technology

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> A cheap VGA + KVM balun kit runs about $130.50 USD: http://www.rackmount-devices.com/019-4068.html

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 No need for it to be this way, each seat would have its own keyboard,
mouse, monitor and data connection (through the monitor cable as they
do right now)

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> The cheapest USB balun I've found is $39.99 USD: http://www.mcmelectronics.com/product/83-11534&CAWELAID=293709399

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 I think the best way to do multiseat is using the shielded monitor
(being used nowadays to transfer video, audio and USB-based data) to
also serve as a true USB hub (this is technically a non issue)

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> Now to get sound to each seat ...

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 You already got sound through the monitor cable

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> Don't forget, because we're having to use USB baluns we're limited to USB 1.1 speeds of 12MB/s.

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 In my sense, not true. Notice that HP's LP2475w (very ;-)) high end
monitor comes with 6 USB 2.0 connectors. SOme of which -may- be even
used for the keyboard and mouse and it comes with an upstream USB 2.0
connection (which I think only works with pen drives (I would only be
nicely surprised to learn that it reliably handles micro drives, too))

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 http://h18000.www1.hp.com/products/quickspecs/13134_na/13134_na.pdf

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 tomshardware.com: lbrtchx "Which LCD displays can handle bus-powered
2.5" microdrives?"

 tomshardware.com: lbrtchx "Any experience with 4 head low
profile/small form factor video cards?"

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> This doesn't include a video card for each seat in the host

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 San, buddy, I think you may want to read up on/tinker a more bit with
the whole multiseat idea. This is exactly what you don't need. I
looked for the newegg link, but they don't offer you the number of
heads in a card as a search option and on ebay (very good) Matrox
4-head video cards are being practically given out

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> Our sum total is $130.50 + $39.99 + $12.99 + $7.99 + $32.99 = $224.46 USD.

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 That sum should be reconsidered ;-)

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> This doesn't include the additional runs of in wall CAT5 to support USB (two runs total).

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 In a friendly and technically honest way, what the f#ck are you
taking about? I would like to understand you because I am not
primarily a hardware guy. Why would you need "CAT5 to support USB"?

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> You can't beat the marketplace, ever.  You can only adapt what it offers to best meet your needs.  From a total ROI standpoint, a cheap PC at every desk offers the best ROI.

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 ...

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> The point being, the industry and corporate worlds have already done all of the ROI, and concluded exactly the argument I'm making here.

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 I would like to read up on their business analysis (which honestly
and as I have detailed here I find "questionable" from a technical
point of view) Could you provide me/us with some studies/data on which
these analysis are based? and as we well know the industry and
corporate worlds milk moneys the way they (know how to) do.
Technically speaking, it doesn't mean that things -must- be a certain
way. besides I have worked for the industry and corporate worlds and
these (in general and like politicians) aren't specially
smart/honest/infallible people

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> What happens when you blow up your X.org config after and upgrade?  Or anything else breaks after an upgrade?  It affects all seats.  With individual PCs ...

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 As we technical people well know "things don't just break". You could
keep your X.org config file (if that is what you mean) in a directory
you mount read-only, protect with SELinux and check once in a while
with smartmontools this would be in addition to safely keep your
backups updated. You could even get a little more paranoid and use one
of those SCSI drive which you can physically set as read only and
ensure that the box is getting a stable power supply with no a little
spikes and brown outs ...

You could keep your X.org config file in a directory you mount
read-only, protect with SELinux and check once in a while with
smartmontools this would be in addition to safely keep your backups
updated

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> For each reason to do multi-user computing on one host there are 10 reasons against it, cost and otherwise.

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 From which model? Do you mean the fat server/thin client one? This is
not what multiseat is all about!!! Multiseat-managed environments
haven't even been exploited yet! That is why so many people have a
hard time even articulating the idea

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 I have also pointed out a number of technical issues that need to be
resolved for multiseat technologies to be truly feasible

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 Thanks

 lbrtchx