Ubiquitous computing, also known as pervasive computing, refers to a post-desktop model of human-computer interaction where computing is integrated into everyday objects and activities in a way that is invisible to the user. The document discusses the history and definitions of ubiquitous computing, including Mark Weiser's vision of making many computers available throughout the physical environment but making them effectively invisible. It also covers related areas like augmented reality, ambient intelligence, and properties of ubiquitous computing systems like being networked, distributed, context-aware, and able to operate autonomously.

1. Ubiquitous computing
Priti Punia
mailpriti@gmail.com
Abstract-Ubiquitous or Pervasive (omnipresent) computing is a
post-desktop model of human-computerinteraction in which
information processing has been thoroughly integratedinto
everyday objects and activities. As opposed to the desktop
paradigm, in which a single userconsciously engages a single
device for a specializedpurpose, someone "using" pervasive
computing engages many computational devices and systems
simultaneously, in the course of ordinary activities, and may not
necessarily even be aware that they are doing so, (or in other
words it means availability andinvisibility). Ubicomp
environments involve the interaction, coordination, and
cooperation of numerous, casually accessible, andoften invisible
computing devices. The world is no more a desktop. Digital
devices getting themselves adjustedin human world, behaving
like human assistantsin an invisible way to make it more easy
and fast for humans.
This paper describes the history of Ubiquitous Computing,
present scope, and the ongoing progress in this fieldby the
various organizations aroundthe world along with the challenges
this technology is facing.
Introduction
Definitions-
Ubiquitous computing is the method of enhancing computer
use by making many computers available throughout the
physical environment, but making them effectively invisible
to the user – Mark Weiser ,Father of Ubiquitous Computing
Ubiquitous computing, or calm technology,is a paradigm shift
where technology becomes virtually invisible in our lives.
-- Marcia Riley
(Georgia Institute of Technology,Atlanta.) A few thousand
years ago people of the Fertile Crescent invented the
technology of capturing words on flat surfaces using abstract
symbols: literacy. The technology of literacy when first
invented, and for thousands ofyears afterwards, was
expensive, tightly controlled, precious. Today it effortlessly,
unobtrusively,surrounds us.Look around now: how many
objects and surfaces do you see with words on them?
Computers in the workplace can be as effortless, and
ubiquitous,as that. Long-term the PC and workstation will
wither because computing access will be everywhere: in the
walls, on wrists, and in "scrap computers" (like scrap paper)
lying about to be grabbed as needed. This is called "ubiquitous
computing", or "ubicomp".
Ubiquitous computing has as its goal the enhancing computer
use by making many computers available throughout the
physical environment, but making them effectively invisible
to the user. A number of researchers around the world are now
working in the ubiquitous computing framework. Their work
impacts all areas of computer science, including hardware
components (e.g. chips), network protocols,interaction
substrates (e.g.software for screens and pens), applications,
privacy, and computational methods
Ubiquitous computing is not virtual reality, it is not a Personal
Digital Assistant (PDA) such as Apple's Newton, it is not a
personal or intimate computer with agents doing your bidding.
Unlike virtual reality, ubiquitous computing endeavers to
integrate information displays into the everyday physical
world. It considers the nuances ofthe real world to be
wonderful, and aims only to augment them. Unlike PDA's,
ubiquitious computing envisions a world of fully connected
devices, with cheap wireless networks everywhere; unlike
PDA's, it postulates that you need not carry anything with you,
since information will be accessable everywhere. Unlike the
intimate agent computer that responds to one's voice and is a
personal friend and assistant,ubiquitous computing envisions
computation primarily in the background where it may not
even be noticed.
History:
Mark Weiser coined the phrase "ubiquitous computing"
around 1988, during his tenure as Chief Technologist of the
Xerox Palo Alto Research Center (PARC). Both alone and
with PARC Director and Chief Scientist John Seely Brown,
Weiser wrote some of the earliest papers on the subject,
largely defining it and sketching out its major concern.
Related Aereas to Unicomp-

2.  Augmented reality :
Augmented reality (AR) is considered as an extension of
Virtual Reality. Virtual Reality (VR) is a virtual space where
the player immerses themselves into that exceed the bounds of
physical reality. Augmented Reality is a live, direct or
indirect, view of a physical, real-world environment whose
elements are augmented by computer-generated sensory input
such as sound,video, graphics or GPS data. It is related to a
more general concept called mediated reality, in which a view
of reality is modified (possibly even diminished rather than
augmented) by a computer. As a result, the technology
functions by enhancing one’s current perception of reality. By
contrast,virtual reality replaces the real world with a
simulated one.
Wikitude World Browser on the iPhone 3GS uses GPS and a
solid state compass
Research explores the application of computer-generated
imagery in live-video streams as a way to enhance the
perception of the real world. AR technology includes head-
mounted displays and virtual retinal displays for visualization
purposes,and construction of controlled environments
containing sensors and actuators.
Ambient intelligence :
In computing, ambient intelligence (AmI) refers to electronic
environments that are sensitive and responsive to the presence
of people. Ambient intelligence is a vision on the future of
consumer electronics, telecommunications and computing. As
these devices grow smaller, more connected and more
integrated into our environment, the technology disappears
into our surroundings until only the userinterface remains
perceivable by users.The ambient intelligence paradigm builds
upon pervasive computing, ubiquitous computing, profiling
practices, context awareness,and human-centric computer
interaction design and is characterized by systems and
technologies that are :
- embedded: many networked devices are integrated
into the environment
- context aware: these devices can recognize you and
your situational context
- personalized: they can be tailored to your needs
- adaptive: they can change in response to you
- anticipatory: they can anticipate your desires without
conscious mediation.
 Context-aware pervasive systems
 Human-centered computing
Human-centered computing (HCC) is an emerging,
interdisciplinary academic field broadly concerned with
computing and computational artifacts as they relate to
the human condition. Some researchers focus on
understanding humans,both as individuals and in social
groups,by focusing on the ways that human beings adopt,
adapt, and organize their lives around computational
technologies.
 Human-computer interaction
Human–computer Interaction (HCI) involves the study,
planning, and design of the interaction between people
(users) and computers
 Smart device
A smart device is an electronic device that is cordless (unless
while being charged), mobile (easily transportable),always
connected (via WiFi, 3G, 4G etc.) and is capable of voice and
video communication, internet browsing, "geo-location" (for
search purposes)and that can operate to some extent
autonomously.The most famous devices at time of writing are
the Apple iPhone and iPad, followed by devices such as the
Samsung Galaxy tablet. The term can also refer to a
ubiquitous computing device: a device that exhibits some
properties of ubiquitous computing including artificial
intelligence. Smart devices can be designed to:
 support a variety of form factors
 support a range of properties pertaining to ubiquitous
computing
 be used in any combination of three main system
environments: physicalworld, human-centred
environments and distributed computing
environments.

3. Form factors
Mark Weiser proposed three basic forms for ubiquitous
systemdevices: tabs, pads and boards.[1]
 Tabs: accompanied or wearable centimeter sized
devices, e.g., smartphones,smart cards
 Pads: hand-held decimeter-sized devices, e.g.,
laptops
Ubiquitous Computing Properties
Weiser’s vision for ubiquitous computing can be summarized
in terms of three core properties:
 Devices need to be networked, distributed and
transparently accessible.
 Human Computer Interaction with devices is hidden
to a degree from its users.
 Devices exhibit Context awareness of an
environment in order to optimise their operation in
that environment.
It is proposed that there are two additional core types of
properties for UbiCom systems [2]:
 Devices can operate to some extent autonomously,
i.e., without human intervention, be self-governed.
 Devices can handle a multiplicity of dynamic actions
and interactions, governed by intelligent decision-
making and organizational interaction. This may
entail some form of [artificial intelligence] in order
to:
o handle incomplete and non-deterministic
interactions
o cooperation and competition between
members of organizations
o richer interaction through sharing of
context, semantics and goals etc.
However, It is hard to fix a closed set of properties that define
all ubiquitous computing devices because of the sheerrange
and variety of ubiquitous computing research and
applications. Rather than to propose a single definition for
ubiquitous computing, a taxonomy of properties for
ubiquitous computing has been proposed,from which
different kinds or flavours of ubiquitous systems and
applications can be composed and described.[2]
Environments
The term Smart Device Environments has two meanings. First,
it can refer to a greater variety of device environments. Three
different kinds of environments for devices can be
differentiated [2]:
 Virtual computing environments that enable smart
devices to access pertinent services anywhere and
anytime.
 Physical environments that may be embedded with a
variety of smart devices of different types including
tags,sensors and controllers. These can have
different form factors ranging from nano to micro to
macro sized.
 Humans environments: humans, either individually
or collectively, inherently form a smart environment
for devices. However, humans may themselves be
accompanied by smart devices such as mobile
phones,use surface-mounted devices (wearable
computing) and contain embedded devices (e.g.,
pacemakers to maintain a healthy heart operation).
Second, the term Smart Device Environments can also refer to
the concept of a smart environment which focuses more
specifically on the physical environment of the device. The
physical environment is smart because it is embedded or
scattered with smart devices that can sense and control part of
it.
Smart Devices versus Services
Devices may access oroffer one or many services from other
devices. Services may be split across several devices or be
offered by multiple types of services. Service models tend be
oriented towards virtual computing environment service use
and Internets with seemingly unbounded resources.Devices
embody bounded resources that constrain service use.Weiser
has referred to this concept of devices being ubiquitous yet
bounded as embodied virtuality.

4. Smart Devices
 Ubiquitous learning
uLearning may use more context awareness to provide
most adaptive contents forlearners.Here is another
meaning for "ubiquitous learning", saying, how to lower
the barriers for end users to learn how to handle/controlor
even co-design ubiquitous apps in future ubiquitous
computing (ubicomp) environments. Ubicomp is
extending the computing domain from desktop computers
to sensor-augmented smart objects (e.g., smart furniture,
smart cups). By analyzing the sensed intelligence from
smart objects,ubicomp applications can sense the
ambient context change and adapt their behavior to assist
users.Compared to desktop applications, ubicomp
applications are more deeply and widely embedded into
our daily lives which requires more complex knowledge
on userrequirement understanding,heterogeneous sensor
data processing,application/device administration, and
hardware/software failure handling.
 Virtual reality
Virtual reality (VR),is a term that applies to computer-
simulated environments that can simulate physical
presence in places in the real world, as well as in
imaginary worlds. Most current virtual reality
environments are primarily visual experiences, displayed
either on a computer screen or through special
stereoscopic displays,but some simulations include
additional sensory information, such as sound through
speakers or headphones.Some advanced, haptic systems
now include tactile information, generally known as force
feedback, in medical and gaming applications.
Furthermore, virtual reality covers remote communication
environments which provide virtual presence of users
with the concepts of telepresence and telexistence or a
virtual artifact (VA) either through the use of standard
input devices such as a keyboard and mouse, or through
multimodal devices such as a wired glove, the Polhemus,
and omnidirectional treadmills. The simulated
environment can be similar to the real world in order to
create a lifelike experience—for example, in simulations
for pilot or combat training—or it can differ significantly
from reality, such as in VR games. In practice, it is
currently very difficult to create a high-fidelity virtual
reality experience, due largely to technical limitations on
processing power, image resolution, and communication
bandwidth; however, the technology's proponentshope
that such limitations will be overcome as processor,
imaging, and data communication technologies become
more powerful and cost-effective over time.
 Virtual reality is often used to describe a wide variety
of applications commonly associated with
immersive, highly visual, 3D environments.
U.S. Navy personnelusing a VR parachute trainer
 Wearable computer
Wearable computers are miniature electronic devices that
are worn by the bearer under, with or on top of clothing.
This class of wearable technology has been developed for
general or special purpose information technologies and
media development. Wearable computers are especially
useful for applications that require more complex
computational support than just hardware coded logics.
I'm Watch smartwatch with Android.jpg

5. One of the main features of a wearable computer is
consistency.There is a constant interaction between the
computer and user, i.e. there is no need to turn the device on
or off. Anotherfeature is the ability to multi-task. It is not
necessary to stop what you are doing to use the device; it is
augmented into all otheractions. These devices can be
incorporated by the user to act like a prosthetic.It can
therefore be an extension of the user’s mind and/orbody.
 Task computing
A Task Computing Framework (TCF) is a framework that
supports TaskComputing, by providing support for:
- The workflows of Task Computing, i.e., at a
minimum, Discovery, followed by Composition and
Execution
- Semantic description of tasks and services
- Specification, Execution and Re-Usability of tasks by
end-users
- Manipulation including creation and disposalof
services by the end-users
Ubicomp Systems : Progress, Opportunities, and Challenges
Two key visions—Calm Computing and Ambient
Intelligence. In 1991, Weiser envisioned a world where
interaction occurs with everyday but computationally
augmented artefacts using natural interactions, our senses,and
the spoken word—Sal’s alarm clock senses when to interact
with her to trigger the brewing of coffee; augmented reality
window displays add first to her perception of her
neighbourhood’s movements, then the activity of her remote
colleagues. It’s a calm world where information seamlessly
moves in and out of attention as automation gives way to
human interaction. Digital and physical are tightly integrated:
Sal locates a missing manual by virtue of its embedded tag;
her ‘foreview mirror’ helps her transit to work and park more
efficiently. Particularly radical at the time, Sal accesses not
one computer but many, and these work together as a single
seamless entity.It’s a future where computation augments the
senses, and the interconnectedness of information, the
environment, and devices enables them to work in concert to
support everyday life—for convenience and enhanced
productivity.We should consider how ubicomp technologies
can be designed to augment the human intellect so that people
can perform ever greater feats, extending their ability to learn,
make decisions, reason, create,solve complex problems and
generate innovative ideas
Challenges
A. UbiquitousData
In the current social and political climate, we cannot imagine
any kind of technology being relied upon as a sufficient
guarantorto enable us to pass through airport security without
close scrutiny—could we ever trust a ubicomp environment to
do this? This scenario raises several important questions about
the ‘data in ubicomp’, its trustworthiness,and access to it:
1) When can we infer with certainty? One reason we might
not trust ubicomp with recognising our identity is that sensed
interactions are imprecisee observations of the world, often
taken from multiple sensors and at varying points in time—
ubicomp environments need to weigh this evidence and make
a judgement of when and how to react. The severity and
importance of the outcome is certainly application- and
context-dependent
2) Where is ubiquitous data located?
Ubiquitous access to data raises the important question of
where ubiquitous data lives. Certainly, a global ubiquitous
data store is not practicable for capacity, bandwidth, latency,
and availability reasons.But neither is it desirable. For many
environments such as rooms, homes, companies, and
hospitals,the demands for security and privacy require
enforcement of conventional or physical ‘boundaries’.
3) How long should data persist and who can access it? What
does the environment know about us? What should it know
and what should we trust it with? How long should data be
retained? What is transient and what should persist? Can we
delete it, and can be forgotten? To enact the foreview mirror,
Sal needs access to information about free space in the car
park. Intuitively it seems acceptable that this is public
information. However, if the data is more intrusive and can
identify particular vehicles or persons,then suddenly the uses
to
which it can be put are more insidious and the need for tighter
control more exigent. In typical ubicomp systems, data is
closed to the experimenters who deploy the systemor
experiment, and the choice as to what’s kept and forgotten by
the systemis often under articulated, so this issue is not
addressed.To enable open scientific use of ubicomp sensing,
or even, ubicomp crime-scene forensics, the issue of data
persistence and access control
comes to the fore. This is even more challenging in ubicomp
as often notions of identity are weak.
4) How do we express our privacy wishes? What is tracked
and shared by the environment, and what remains private to
the individual, is still very much unsolved.
A key challenge of creating ubicomp systems that can be
deployed in more than one environment and for substantial
periods of time, is the degree of change or volatility
experienced:
1) Volatility:
The changing environment. Not only does the world change
(and thus so should our computational understanding of it, as
alluded to above), but so the set of users,devices and software
components in an environment change over time—far more
frequently in ubicomp systems than in conventional
distributed systems.This implies the creation and destruction

6. of associations— logical communication relationships—
between software components resident on the devices.It also
implies failures where communication is no longer possible
between them. But change also brings opportunities,as new
resources with different capabilities come into play. The
systemmust be designed to incorporate change and failure
within normal operating parameters and gracefully adapt or
degrade appropriately.
2) Responding to volatility:
Adaptation.
3) Evolution:
Adapting to the unexpected. The goal should be ‘open loop’
adaptation,i.e. the ability for the environment to cope with
users,devices and software it has not seen before.
Various otherchallenges-
Work on ubiquitous computingis still atan early phase.Most
work now is concentratingon the mobileinfrastructurefor
wireless networking. Because ubiquitous computing
envisions hundreds of wireless computers in every office, its
need for wireless bandwidth is prodigious.For instance,I
work in a not-very-large buildingwith 300 other people. If
each of us has 100 wireless devices in our offices,each
demanding 256kbits/sec,we are using7.5 gigabits of
aggregate bandwidth in a singlebuilding.This isdifficultto
achievewith currently envisioned wireless technologies.
A second challenge of the mobile infrastructure is handling
mobility. Networking developed over the past twenty years
with the assumption that a machine's name, and its network
address,was unvarying. However, once a computer can move
from network to network this assumption is false. Existing
protocols such as TCP/IP and OSI are unprepared for to
handle machine mobility without change.A number of
committees and researchers are now working on methods of
augmenting or replacing existing protocols to handle mobility.
A third challenge of the mobile infrastructure is window
systems.Most window systems,such as those for the
Macintosh and for DOS, are not able to open remote windows
over a network. Even window systems designed for
networking, such as X, have built into them assumptions
about the mobility of people. The X window systemprotocol,
for instance,makes it very difficult to migrate the window of a
running application from one screen to another, although this
is just what a person traveling from their office to a meeting
might want.
Networking,Mobility,Scalability,Realiability in short are
issues to be considered.
III. Opportunitiesfor growing the infrastructure
A. Utility Computing in the Cloud
Utility computing can help realize the ubiquitous computing
vision by providing large-scale and long-lived storage and
processing resources for personal ubicomp applications. The
notion of a utility that makes computing resources available to
the public, analogous to an electric or telecommunications
utility.
This notion has become reality in recent years with the rise of
cloud computing services such as Amazon’s Elastic Compute
Cloud, which offers pay-as-you-use resources in the form of
virtual machines. For instance,they would allow individuals
to packages are installed on their virtual machines, and to
insist that any data formats used be open and portable. While
utility computing in the cloud can provide important backend
resources for ubicomp applications, it cannot provide all the
necessary infrastructure.
B. Internet of Things
In our opinion, a key problem in wider adoption of ubicomp is
the tight coupling with particular embedded infrastructure.
This has led researchers to become increasingly ingenious in
considering how they might exploit infrastructures out there
for other purposes,such as the cell phone network, power
lines, and frequently smart phones and users themselves.
Buildings incorporate sensors , motion-triggered lighting,
intruder detection,fault detection, and so on. Even domestic
homes increasingly have security and heating systems with
room-level sensors that detect motion and the opening and
closing of windows and doors. Some commercial appliances
(e.g. elevators, copiers) can already ‘call home’ for
engineering support in the event of failure. Our cars are
becoming increasingly densely sensed, not only for measuring
the ongoing operation of the car and the environment it
encounters,but also increasingly for the safety and comfort of
passengers.Then there are sensors in our civic infrastructure
and roads.All this increasing ‘smartness’ is surely an
opportunity to the ubicomp community, providing this
infrastructure were open to us.
Outlook for large-scale deployment
While there have been many successfulresearch prototypes of
ubicomp systems,we do not believe the technology in such
prototypes will see wide adoption until a number of difficult
issues are resolved. Two of the main issues are more
economic than technical: Who will pay for ubicomp systems
and who will manage them?
Conclusions
In the twenty years since Weiser articulated the ubiquitous
computing vision, a large and vibrant research community has
grown around the ubicomp concept. Numerous successful
prototypes have been built and evaluated, demonstrating the
utility of many different aspects ofubicomp systems.In that
same timeframe, digital technology has made great advances,
enabling products and services that are complementary to the
ubicomp vision and have become part of the everyday lives of
billions of people. Arguably the most successfulof these
products is the mobile phone,which places increasing
amounts of computing, sensing,and communication
capabilities in the hands of a significant portion of the earth’s

7. population. However, despite this progress and the continuing
opportunities
for further advances,formidable challenges remain to be
overcome before we can realize many of the core ubicomp
scenarios such as Calm Computing and Ambient Intelligence
on any large scale.
Current research:
Ubiquitous computing touches on a wide range of research
topics, including distributed computing, mobile computing,
sensornetworks, human-computer interaction, and artificial
intelligence.
Conclusion:
Strengths
• The paper identifies certain key features of
Ubiquitous applications
• Exemplifies these features with real-life projects
• Correlates SE challenges pertaining to such pattern of
application development
Accordingly, it proposes changes that need to be inculcated in
the stream of Software Engineering
Weakness
- The paper only looks into ‘Rapid Prototyping’
paradigm of application development
- It overlooks other models and approaches available
for UbiComp application development.
(probable challenges therein have not be catered for)
References
[Suchman 85]. Suchman, Lucy A. Plans and Situated Actions:
The problem of human-machine communication.Xerox PARC
Technical Report ISL-6. February 1985
[Weiser91] Weiser, Mark. The Computer for the Twenty-First
Century. Scientific American. September 1991. pp. 94-104.
Mark Weiser's original material dating from his tenure at
Xerox PARC:
 Ubiquitous Computing
Links referred:
 Context and Adaptivity in Pervasive Computing
Environments: Links with Software Engineering and
Ontological Engineering.
 Yesterday’s tomorrows: notes on ubiquitous
computing’s dominant vision, by Genevieve Bell &
Paul Dourish.
 http://www.interaction-
design.org/encyclopedia/context-
aware_computing.html
 Towards pervasive computing in health care – A
literature review, article in BMC Medical Informatics
and Decision Making (Open Access journal) by
Carsten Orwat, Andreas Graefe and Timm
Faulwasser.
 Pervasive Technology Lab (CIC) Pervasive
Technology to Help People with Mental Health
Problems.
 Wwikipedia/ubiquitous computing
 Google.com/images