Re: Mainframe -> PC -> Mainframe

Thus quoth Chris Knadle on Mon, Aug 25, 2003 at 01:27:51PM -0400:
> 
> Mainframe -> PC
>    Years ago, mainframes were very expesnive (and thus rare) and storage space 
> was a premium.  Users were generally limited in the program sizes they could 

8 KB of memory might have been dandy for a mainframe by 1960, but by 1980 it
would be more like 1 MB, by which time microcomputers sported 8 KB. 

> PCs and users
>    The real point of personal PCs (in my opinion) was mostly a matter of 
> having a system in front of the user that didn't unexpectedly change, as well 
> as giving the user the ability to have constant access to the user's work, 
> something previously impossible for most people.  

The ability to control your own computer was an important benefit for the 
Personal Computer. The lower price made it affordable for menial tasks like
word processsing. 

> As computers got faster and 
> easier to use, user expectations grew.  This ease of use came at a cost: 
> users did not have to do any difficult setup or debugging of their machine, 
> but were also typically _shielded_ from that information, making it more 
> difficult for them to learn.  [The the typical "help" from some of the newer 
> operating systems from "a popular software company" is a prime example.]  It 

A microcomputer would be inherently simpler than a mainframe, which required a
team of operators. (if only to feed the printers and distribute printouts and
fetch the tapes from the cellar). The 'help' command on a mainframe would be
for sending some request message to the operator. 

Mainframes had complex operating systems and other software to shield the
user from the hardware. On early micros the user had access to the hardware,
might solder their own extension boards and program in assembly language. 
The main advantage of MS-DOS is that it does not shield the hardware from you.

If you go further back to 1950, a mainframe was in fact run by a single person
at a time, and a user got maybe an hour to run her programs before the next
one. Mainframes started about as simple and primitive as microcomputers in
the seventies. By 1990 the personal computers had become complex with
multitasking Operating Systems and GUIs, which helped to manage the complexity
somewhat by shielding the user from the innards. 

>    The question in my mind is: are their drawbacks to having free software on 
> PCs that will eventually drive that away yet again back to commercial 
> software?  Is that cyclic?
 
Mainframe software was and is expensive, but when amortised over a thousand
users, a mainframe can be cheaper than a PC solution. The free software
community was mostly found on universities, banks used commercial software.
A new free software movement was centered around the early microcomputers,
which users had to build themselves. There is still lots of shareware for
MS-DOS. 

When IBM introduced its Model PC in 1981, it quickly became standard office
equipment, and the commercial software market grew very fast. Microsoft
makes the bulk of its income from the commoditised Windows OS and Office 
application suite. As PCs became more capable and complex, they hardly
got cheaper, and today's information professional prefers the notebook
over the cheaper desktop. (notebooks break more easily, get stolen more
often, are harder to upgrade, and you get RSI faster unless you hook
up an external keyboard, external mouse, and external monitor). 

Linux was the killer app of the Free Software / Open Source movement, 
and it commoditised the OS and Office suite. It also commoditised the
server software. Linux is also making inroads in the supercomputing world.
In the PDA and mobile phone business it is struggling hard with Windows CE.

Commercial software has a future in every place where free software does
not meed the user's needs. Companies and governments continue to buy
tailor-made software. There is no reason why a piece of software could not
be sold commercially under the GPL license.

The recession caused the software market to shrink, and helped to foster
cheaper alternatives. The (earlier) dot-com boom left us with a large
number of (web, e-commerce) servers, with a demand for managing them. 
Following 11 sept.'01 the demand for security grew, and the continuing
computer virus epidemics foster them. These demands remain unfulfilled 
because companies cut back on IT budgets. 

Most of the commercial potential is probably in system and network
administration and management. Linux is rather laborious to manage.
The big vendors are all working on complex software, and intend to 
make money from it. The number of system administrators (and their
cost) is starting to exceed the number of application programmers.

Kind regards,


Daniel von Asmuth

-- 
	wat heb je nodig bij een uitzichtloos leven? euthanasie?
	nee, windows.
	van microsoft?
	nee, van glas.