Mark Weiser's 1991 article "The Computer for the 21st Century" predicted the rise of ubiquitous computing through specialized hardware and software connected by wireless networks. Weiser envisioned tabs, pads, and boards - mobile devices of varying sizes integrated into everyday life. While technical challenges remained around interoperability and transmission speeds, many of Weiser's predictions have come to pass, with smartphones, tablets, and digital displays now ubiquitous. Weiser was accurate in anticipating how mobile devices would evolve to fit customized tasks and interact seamlessly through wireless protocols. His ideas for microkernel operating systems and cryptography to ensure privacy also reflected the future of computing.

1. IS 746 - ASSIGNMENT 1: The Computer for the 21st Century
"Ubiquitous Computing" and
“Comparing Advancements (in terms of software, hardware and network)
in mobile computing today with the ideas of Mark Weiser in 1991”
Fatih Özlü
1777762
Middle East Technical University
10 April, 2011
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2. Ubiquity and Mark’s Ideas Compared to Today
As people are starting to use the most common technologies just about anywhere, at any time,
as a result they become as a part of our everyday life, though mostly we are not aware of the
fact that any technology is accessible to us at shop, at home, at work, or even from your car
via mobile devices, pads, laptops or embedded systems. This phenomenon is named as
“ubiquity”, as Mark Weiser mentioned about that this kind of ubiquity calculation would
become a part of environment in the forms of live boards, pads, tabs, etc in different sizes and
with different abilities, in his article (Computer for the 21st Century, 1991).
In addition, he gives example of engines that evolves and started to be used in many areas like
for locking and unlocking doors, cleaning the windshield, and so on. So these technologies are
very common and we are not aware of them where they are used until to think about them, in
detail. The introduction sentence of the article reveals the main idea: “Specialized elements of
hardware and software, connected by wires, radio waves and infrared, will be so ubiquitous
that no one will notice their presence.”
Mark supposes that ubiquities computers will be common to help people in all areas of the life
in different sizes, each assigned to a particular task. As he describes, in the “embodied
virtuality”, tabs, pads and boards (yard size displays) participate at every part of the people
life like wall notes, clocks, thermostats, or even a small piece of paper. The smallest ones are
the tabs that will be used as pocket calculator or organizer that can make simple tasks of
people by keeping tracks of people. These components could interact with other mobile
computers, so they can exchange information, for example by shrinking a window onto the
tab. The other ones, Pads about in the size of papers, will become alternative to the windows
and will fulfill many more of paper’s functions. Boards which have large displays will serve a
lot with its screen for meetings, or other forms of collaborations for conference rooms and
open areas.
Compared to today, many similar devices are being used in our everyday lives as Mark has
foreseen. IPods and IPhones or such mobile devices are very common, and people got
accustomed to using them almost as the first necessity. In addition, examples of the boards
can be seen at many areas for advertising of show cards, or scoreboards at stadiums, etc. So
when thinking of these devices could interact between computers or other devices with many
messaging protocols via Bluetooth or infrared, Mark is said to be good at foreseeing.
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3. In the article, Mark adds that “Prototype tabs, pads and boards are just the beginning of
ubiquitous computing.” and specifies that the real power of the concept comes from
interaction of all of them. He takes attention to the fact that linking wired and wireless
networks has some obstacles like common communication protocols or efficient data
transmission rates.
Although these issues are also important to be taken into consideration, the technology is as
advanced as Mark foresighted. The mobile networks are now more interoperated and data
transmission rate is fairly high, so as a result video telephone calls are even available by
mobile phones.
Another Mark’s prediction is about “micro-kernel” operating systems to perform specific
functions can be added or removed without shutting down computers or mobile systems. He
thinks future operating systems based on this principle can shrink quickly “to fit the changing
needs of ubiquitous computation”.
Such an approach to this kind of problem is also important for today’s systems and most
applications have tendency to have a base platform to be developed, though they have not
need to be working mostly while adding a new functionality or removing. At now, most
systems have these abilities.
Last issue to be mentioned is about privacy, as considered in many information systems
applications. Mark specifies that cryptographic techniques can be applied while sending
messages one computer to another one to ensure private data is isolated from the public.
Maybe, today’s the one of most important problems is privacy and to be ensured to safeguard
private information. As Mark suggests his solution to this problem by cryptography, it is one
of the choices can be applied to provide a total private information guard.
As a result, by looking over the article itself, it is not possible to believe that it is an article
with ideas from 1991. Each detail and issue has been nearly implemented or used in the real
life, so it could be said that Mark had come up with exact practical ideas.
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4. REFERENCES
 Mark Weiser, Palo Alto Research Center, Xerox, CA, USA, (September, 1991). The
Computer for the 21st Century.
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