14-06-2009, 01:33 AM
PERVASIVE COMPUTING
A SEMINAR REPORT
Submitted by
M.NESHA RANI
in partial fulfillment for the award of the degree
of
BACHELOR OF TECHNOLOGY
IN
COMPUTER SCIENCE AND ENGINEERING
SCHOOL OF ENGINEERING
COCHIN UNIVERSITY OF SCIENCE &TECHNOLOGY,
KOCHI-682022
AUGUST 2008Page 2
DIVISION OF COMPUTER SCIENCE & ENGINEERING
SCHOOL OF ENGINEERING
COCHIN UNIVERSITY OF SCIENCE &
TECHNOLOGY, KOCHI-682022
Certified that this is a bonafide record of the Seminar Entitled
PERVASIVE COMPUTING
Done by the following Student
M.Nesha Rani
Of the VIIth semester, Computer Scince and Engineering in the year 2008 in
partial fulfillment of the requirements to the award of Degree Of Bachelor of
Technology in Computer Science and Engineering of Cochin University of
Scince and Technology.
Mrs.Dhanya K Sudhish
Seminar Guide
Head of the Department
Date:
CertificatePage 3
ACKNOWLEDGEMENT
At the outset, I thank the Lord Almighty for the grace, strength and
hope to make my endeavor a success.
I also express my gratitude to Dr. David Peter, Head of the
Department and my Seminar Guide for providing me with adequate
facilities, ways and means by which I was able to complete this seminars. I
express my sincere gratitude to him for his constant support and valuable
suggestions without which the successful completion of this seminar would
not have been possible.
I thank Mrs.Dhanya, my seminar guide for her boundless
cooperation and helps extended for this seminars. I express my immense
pleasure and thankfulness to all the teachers and staff of the Department of
Computer Science and Engineering, CUSAT for their cooperation and
support.
Last but not the least, I thank all others, and especially my classmates
and my family members who in one way or another helped me in the
successful completion of this work.
M.Nesha RaniPage 4
ABSTRACT
Pervasive computing is a post-desktop model of human-computer
interaction in which information processing has been thoroughly integrated
into everyday objects and activities. As opposed to the desktop paradigm, in
which a single user consciously engages a single device for a specialized
purpose, 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 and invisibility).
Pervasive computing environments involve the interaction, coordination,
and cooperation of numerous, casually accessible, and often invisible
computing devices. These devices will connect via wired and wireless links
to one another as well as to the global networking infrastructure to provide
more relevant information and integrated services
At their core, all models of pervasive computing share a vision of small,
inexpensive, robust networked processing devices, distributed at all scales
throughout everyday life and generally turned to distinctly quotidian ends.
For example, a domestic pervasive computing environment might
interconnect lighting and environmental controls with personal biometric
monitors woven into clothing so that illumination and heating conditions inPage 5
a room might be modulated, continuously and imperceptibly. Another
common scenario posits refrigerators "aware" of their suitably-tagged
contents, able to both plan a variety of menus from the food actually on
hand, and warn users of stale or spoiled food.
TABLE OF CONTENTS
CHAPTER NO TITLE
PAGE NO
ABSTRACT
LIST OF FIGURES
iii
1.
INTRODUCTION
1
2.
VISION
2
2.1 A PERFECT EXAMPLE
2
3.
CURRENT EMBEDDED TECHNOLOGY
3
3.1 UBIQUITOUS COMPUTING
5
3.2 DISTRIBUTED COMPUTING
6
3.3 SOME PERSONAL USES
7
4.
SENTILLA
8
4.1 SENTILLA SOFTWARE
8
4.2 SENTILLA HARDWARE
9
4.3 SENTILLA SOLUTIONS
10
4.4 SENTILLA LABS
11
5.
SECURITY ,MANAGEMENT ISSUES
12
5.1 ESTABLISHED PRIVACY SOLUTIONS
14
5.1.1 HIP
14
5.1.2 TRUST BASED ARCHITECTURE 17Page 6
6.
FUTURISTIC PROPOSITIONS
19
6.1 CHALLENGES AHEAD
20
6.2 TECHNOLOGY FOR THE FUTURE
21
6.3 RESEARCH AREAS
22
i
6.4 RESEARCH PROJECTS
23
7.
CONCLUSION
24
8.
REFERENCES
25Page 7
ii
LIST OF FIGURES
NO
NAME
PAGE NO
1.
SENTILLA S\W
8
2.
PUBLIC KEYS
16
3.
TRUST BASED ARCHITECTURE
18Page 8
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Pervasive Computing
1. INTRODUCTION
What is Pervasive Computing?
Imagine a world filled with all sorts of gabby electronic devices - traditional desktop computers,
wireless laptops, small PDA ipaqs, smart cell phones, tiny wristwatch pagers, clever little coffee
pots. Imagine all these devices talking easily to one another to bring you the news you need when
you need it, regardless of where you are. You have just imagined the future of Pervasive Computing
(PvC).
Pervasive computing environments involve the interaction, coordination, and cooperation of
numerous, casually accessible, and often invisible computing devices. These devices will connect
via wired and wireless links to one another as well as to the global networking infrastructure to
provide more relevant information and integrated services. Existing approaches to building
distributed applications, including client/server computing, are ill suited to meet this challenge. They
are targeted at smaller and less dynamic computing environments and lack sufficient facilities to
manage changes in the network configurations. Networked computing devices will proliferate in the
userâ„¢s landscape, being embedded in objects ranging from home appliances to clothing. Applications
will have greater awareness of context, and thus will be able to provide more intelligent services that
reduce the burden on users to direct and interact with applications. Many applications will resemble
agents that carry out tasks on behalf of users by exploiting the rich sets of services available within
computing environments.
Mobile computing and communication is one of the major parts of the pervasive computing system.
Here data and computing resources are shared among the various devices. The coordination between
these devices is maintained through communication, which may be wired or wireless. With the
advent of Bluetooth and Ad hoc networking technologies the wireless communication has overtaken
the wired counter part.
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2. VISION
? Small inexpensive computers and sensors
? In every device, appliance and piece of equipment
? In buildings, offices, classrooms,homes
? People carrying portable devices and wearable computers
? Networked to each other and the Internet
? Sensing and reacting intelligently to the environment
? Information instantly accessible anywhere and anytime
? An emerging new paradigm for IT
? Enormous new global market
? Transforming the way people live and learn
2.1 A PERFECT EXAMPLE OF A SMART HOME
The Bill Gates home is a perfect example of a home where ground breaking technologies have been
applied to make the home more livable. It could serve as an epitome of the application of pervasive
computing. A hundred microcomputers and the software that controls them have been embedded in
the home and it makes you experience the home without paying any attention to the technology at its
heart. It provides an intelligent environment around with features like :
? It allows you to listen to your choice of music when you enter the room.
?
The lights goes on when you enter the room , its brightness adjusted to suit the weather
outside.
? High resolution displays present electronic versions of your favourite art on the walls of the
room.
? The room by itself adjusts to the temperature according to the time of the day.
? The home is also equipped with energy saving instruments.
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3. CURRENT EMBEDDED TECHNOLOGY
Embedded technology is the process of introducing computing power to various appliances. These
devices are intended to perform certain specific jobs and processors giving the computing power are
designed in an application oriented way.
Computers are hidden in numerous information appliances which we use in our day-to-day life.
These devices find there application in every segment of life such as consumer electronics, avionics,
biomedical engineering, manufacturing, process control, industrial, communication, defence etc¦
Embedded systems, based on there functionality and performance requirement are basically
categorized as:
? Stand alone systems
? Real time systems
? Networked systems
? Mobile devices
Stand alone systems work in stand alone mode, taking inputs and producing desired outputs. They
do not have any dependence on other systems. Embedded systems in which some specific work has
to be done in a specific time period are called Real time systems. Meeting the dead line is the most
important requirement of a real time system. In Hard real time systems, missing a deadline may lead
to a catastrophe and in Soft real time systems such problem is not present. Systems which are
provided with network interfaces and accessed by networks such as LAN or the Internet are called
Networked Systems. Networking may be wired or wireless. Mobile devices are devices which move
from one location to another, like mobile phones, PDAâ„¢S etc.
Today, many people carry numerous portable devices, such as laptops, mobile phones, PDAs and
mp3 players, for use in their professional and private lives. For the most part, these devices are used
separately i.e, their applications do not interact. However, if they could interact directly, participants
at a meeting could share documents or presentations, business cards would automatically find their
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way into the address register on a laptop and the number register on a mobile phone, as commuters
exit a train, their laptops could remain online; likewise, incoming email could now be diverted to
their PDAs.
In such a distributed environment where several embedded devices has to communicate and co-
ordinate with each other. For this a communication page link is required which may be wired or wireless.
In initial stages of Networked embedded system environments wired connection was preferred as it
provided a safer and faster channel for communication. But the cost, immovability and the cables
running around the floorboards became less attractive. On top of this, dishing out the cash for
network cards, cables and a hub/switch reserved this practice to the more elite computer users, until
wireless networking hit the scene.
Infrared communication was initially used for wireless communication because of the low cost
offered by it. But it suffered from the limitation that it can be used only within Line Of Sight. IEEE
introduced 802.11 as the international standard for wireless LANs. This used a 2.4GHz transmission
band while maintaining a steady 1-2 Mbps bandwidth rate. Being that this was extremely slow
compared to 100Mbit
wired LANs, it took a while for the 802.11 standard to develop into a viable solution, achieved
shortly after with the 802.11a, b and g standards, offering bandwidth ranging from 11Mbps to
54Mbps. Although this is still considerably short of the 100Mbit found in cabled networks, 802.1 x
wireless technologies is now literally regarded as the future of networking. Bluetooth, Wi-Fi, Wi-
Max are the latest solutions, under the 802.1x standard, for wireless communication over short,
medium and long range communication respectively.
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3.1 UBIQUITOUS \ PERVASIVE COMPUTING
Pervasive computing can be explained in two different perspectives:
? User view
? Technology view
User view
For an end user Pervasive approach act as a method of augmenting human abilities in context of
tasks. It provides Interaction transparency which means that the human user is not aware that there is
a computer embedded in the tool or device that he or she is using.
Technological view
It means access to information and software applications are available everywhere and any where.
Technically pervasive computing involves in embedding intelligence and computing power to
devices which are part of our daily life. As the word ËœPervasiveâ„¢ means, we create an environment
with intelligence and which can communicate with each other. This technology is intended for
mobile as well as localized devices. It must also posses the ability to locate an object or a user using
Pr visions such as Global Positioning System (GPS). After positioning, a dynamic page link must be setup
for communication which may use the recent concept of ADHOC networking. User can interact with
and control these devices using steerable interfaces, using voice and gesture recognition facilities.
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3.2 DISTRIBUTED COMPUTING ENVIRONMENT
The essence of that vision was the creation of environment saturated with computing and
communication capability, yet gracefully integrated with human users. The field of distributed
systems arose by the intersection of personal computer and Local Area Network. With the
appearance of wireless LANs embedded systems for mobile clients was introduced. These two laid
the foundation for the concept of Pervasive computing.
Ambient Intelligence
Objects in pervasive environment are considered to have Ambient Intelligence. Ambient Intelligence
refers to a vision of the future, in which people are empowered by an electronic environment that is
aware of their presence, and is sensitive and responsive to their needs. It aims at improving the
quality of life by
creating the desired atmosphere and functionality via intelligent, personalized interconnected
systems and services. The transition to such a world requires a paradigm shift in user-system
interaction. Speech and gesture recognition modalities address user benefits such as freedom of
movement, and are natural candidates for such interactions.
However, implementing these modalities in e.g. a home environment is radically different from
implementing known methods such as buttons, dials and remote controls. Smart objects may play an
important role in bridging this gap. People have a life-time experience in manipulating tangible
objects, and can perform these manipulation tasks with a minimal amount of attention.
Ambient Intelligence refers to electronic environment that are sensitive and responsive to the
presence of people. It builds on advanced networking technologies, which allow robust, ad-hoc
networks to be formed by a broad range of mobile devices and other objects. By adding adaptive
user-system interaction methods, based on new insights in the way people like to interact with
computing devices, digital environments can be created which improve the quality of life of people
by acting on their behalf.
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Key characteristics of such environments are: ubiquity, awareness, intelligence, and natural
interaction. Ubiquity refers to a situation in which we are surrounded by a multitude of
interconnected embedded systems, which are invisible and moved into the background of our
environment. Awareness refers to the ability of the system to locate and recognize objects and
people. Intelligence refers to the fact that the digital surrounding is able to analyze the context, to
adapt itself to the people that live in it, to learn from their behavior, and eventually to recognize as
well as show emotion. Natural Interaction finally refers to advanced modalities like speech-, gesture-
and object recognition, which will allow a more natural communication with the digital environment
than is possible today.
3.3 SOME PERSONAL USES
? Personal Information: PDA with wireless connections to web, broker, child's school,
appointments, telephone numbers
?
Flight Schedules: Your phone rings. Its the computer at American Airlines. Your flight
departure is delayed by 20 minutes.
?
Networked coffee shop: Wi-Fi at StarBuck's and Schlosky's .
?
Location: finding friends at the mall (or hiding from), texting .
? Home interaction: The networked coffee pot/an alarm clock sync'd with Outlook / Electricity
Peak Conservation/Thermostat/Hot Water Heater connected via wireless network (security
issues)
? Car: schedule oil change seamlessly w/ garage; maps; traffic; kid movies streamed to back
seat ("Only if its quiet back there")
? Finding Possessions: "Dude, where's my dog?"
? Luxury : The television infront tunes to your favourite channel of the time when you sit in
the sofa.
? Intelligent Equipment : A single remote to operate all electronic devices.
? Smart Devices : The devices portrays its extreme capabilities without user interference.
? Mobility : Access and control devices even while away at home.
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4. SENTILLA
Sentilla “ Business Organisation that has EXPLOITED this CONCEPT
About Sentilla
Whether saving money, saving lives, or saving the planet, Sentilla is transforming business. We
bring intelligence to places it has never been before, enabling applications in energy management,
security, greentech, and more. We created software designed to run on small, wireless devices
deployed by the billions throughout our world. And we use that software in concert with a hardware
platform and services team to create real applications solving real problems, right now.
4.1 SENTILLA SOFTWARE
Sentilla Software is central to a successful pervasive computing solution. It all starts with Sentilla
Point, Java-Powered software platform for pervasive-class computers. Sentilla Point contains the
operating system, virtual machine and system libraries that enable devices to effectively manage
power, form mesh networks, and create applications that manage energy usage in the real world.
Fig 4.1 : Sentilla S/w
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Sentilla Work, our Eclipse-based Integrated Development Environment, makes creating these
programs simple and easy. It provides you with a single environment for the development,
debugging, installation, and testing of solutions in a straightforward and familiar way.
Bringing it all together is Sentilla Server, our PC-class software that enables the pervasive
computers in your network to connect to your enterprise infrastructure. We take a service-oriented
architecture approach in this software, enabling companies to effectively integrate and manage a
pervasive-computing based solution using well-known, standard interfaces.
Contact a Sentilla sales representative today at sales[at]sentilla.com to learn about our flexible
software licensing programs and how Sentilla can help you complete your energy-management
pervasive computing solution.
4.2 SENTILLA HARDWARE
Sentilla Mini is the core of your pervasive computing solution. Combining the immensely popular
Texas Instruments MSP430 microcontroller with a TI/Chipcon CC2420 low-power wireless radio,
the Mini comes in a standard MiniSDIO form factor specifically designed for flexibility and
scalability.
More important, each Mini comes pre-bundled with Sentilla Point, the worldâ„¢s only Java-compliant
software platform for pervasive computers. The combination of standard hardware, in a standard
form factor, bundled with standard software means that developers, OEMs, and system integrators
can concentrate on building applications rather than platforms -- Sentilla has taken care of the rest in
a less than one-square-inch package. With the Mini, you can quickly and easily create a device that
allows you to manage your energy usage directly at the source of consumption.
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4.3 SENTILLA SOLUTIONS
? Energy Management
By embedding computers in the world around us, a new revolution in computing is making "the
invisible visible" by analyzing real world conditions directly at the source of power usage. Attached
to everything from residential power meters to massive metal smelters, pervasive computers control
energy consumption directly at the point of activity, consumption, or change. Take control of your
energy usage today.
? Safety and Security
Detection, assessment and response systems meld to form the core of our safety and security
infrastructure. However, this traditional approach is often slow to react since each disparate system
is frequently tens or even hundreds of miles apart from one other. Pervasive computing systems can
get you closer to the real-world situation, giving you a real-chance to stop real-problems. Sentilla's
solution services based on our unique software platform can combine detection, assessment and
response into a single system integrated directly into your existing infrastructure, giving you to the
instant-response capability you need to save lives and property.
? Logistics
Logistics and Asset Management is more than just keeping track of a warehouse full of goods. Itâ„¢s a
complex operation that has a seemingly infinite number of interacting parts, many of which are
constantly in motion. Current systems do a decent job of getting things where they need to go and
telling us when they get there. But pervasive computing can take you to the next level: providing the
real-world information about the condition of your goods in real-time, giving you a real advantage
against your competitors. Sentilla's solution services based on our unique software platform can give
you the operational insight you need where other technologies like RFID have failed.
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4.4 SENTILLA LABS
We can categorize the applications on Sentilla Labs into three buckets:
?
Bite-sized versions of large-scale industry applications. One project is a refrigerator
monitor. It uses two pervasive computers -- one inside a refrigerator and one outside -- to
alert us when someone leaves the fridge door open. The same application has been used to
retrofit large industrial refrigeration systems to save energy and control temperature.
?
Developer applications and prototype hardware. If you've wanted to set up a sensor to
detect when your kids come home late at night, here's the plan. The Motion Detector project
uses a Radio Shack infrared detector to alert you when there's movement. Think of it as a
programmable home security system. You could extend it to turn your lights on and off, just
like in your office.
?
Fun applications. No software product is complete without the presence of a game. And
what game is more fitting than the classic, Pong. Built using accelerometers in the Sentilla
Perk kit, two people go head-to-head and the score is shown on their pervasive computing
"paddle". One of my favorite applications to demo!
5. SECURITY AND MANAGEMENT ISSUES
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Security
? Interactions cross multiple organisational boundaries
?
Specification, analysis and integration for heterogeneous OS, databases, firewalls, routers
? Lessons from history:
? Cell phones, IR garage doors, CATV decoders
? Everything worth hacking gets hacked
? Need for secure Ëœout of the boxâ„¢ set up
?
Identify friend or foe - level of trust
?
Small communicators, with confidential data, are easily lost or stolen “ biometric
authentication.
? Necessary security technology exists
Privacy
?
Location service tracks movement to within metres (cf mobile phones but pay-as-you-go can
be anonymous).
?
Clearly indicate you are being sensed or recorded + user control to stop recording or control
distribution of information
? You are now predictable
? System can co-relate location, context and behaviour patterns
?
Do you want employer, colleagues or insurance company to know you carry a medical
monitor?
?
Tension between authentication and anonymity “ business want to authenticate you for
financial transactions and to provide Ëœpersonalizedâ„¢ service cf web sites
? Constant spam of context dependent advertising
Management “ the nightmare!
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? Huge, complex systems
? Billions of processors
? Multiple organisations
?
Managing physical world, controlling sensors, actuators
? Humans will be in the way
? Errors propagate to bring down complete regions
? Hacker and virus paradise
?
System propagates false information about individuals or organisation
?
Complexity of s/w installation on a workstation or server “ how do you cope with billions?
Management solutions
? Intelligent agents, mobile agents, policy
? Fat pipes and large storage can convert media streams to short traffic bursts in core network
but still needed for wireless links
? Adaptive self-management is the only answer
? Partitioned domains of responsibility
? Genetic algorithms may be suitable for long-term strategy but need more deterministic
solutions for short term decision making
? Remove human from the loop
5.1 SOME ESTABLISHED PRIVACY SOLUTIONS
.
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? Establish strong identity
?
Goal: Cryptographically strong identity to devices (endpoints)
? Means: Host Identity Protocol (HIP)
? Assign and manage trust and authority
?
Goal: Decentralised means for managing authorisation
? Means: SPKI certificates
5.1.1 HOST IDENTIFICATION PROTOCOL
The Host Identity Protocol (HIP) provides a method of separating the end-point identifier and
locator roles of IP addresses. It introduces a new Host Identity (HI) name space, based on public
keys. The public keys are typically, but not necessarily, self-generated.
PUBLIC KEYS
Public-key cryptography, also known as asymmetric cryptography, is a form of cryptography in
which the key used to encrypt a message differs from the key used to decrypt it. In public key
cryptography, a user has a pair of cryptographic keysâ€a public key and a private key. The private
key is kept secret, while the public key may be widely distributed. Incoming messages would have
been encrypted with the recipient's public key and can only be decrypted with his corresponding
private key. The keys are related mathematically, but the private key cannot be practically derived
from the public key.
Conversely, secret key cryptography, also known as symmetric cryptography uses a single secret key
for both encryption and decryption. To use symmetric cryptography for communication, both the
sender & receiver would have to know the key beforehand, or it would have to be sent along with the
message.
The two main branches of public key cryptography are:
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?
Public key encryption †a message encrypted with a recipient's public key cannot be
decrypted by anyone except the recipient possessing the corresponding private key. This is
used to ensure confidentiality.
?
Digital signatures †a message signed with a sender's private key can be verified by anyone
who has access to the sender's public key, thereby proving that the sender signed it and that
the message has not been tampered with. This is used to ensure authenticity.
Some encryption schemes can be proven secure based on the presumed hardness of a mathematical
problem like factoring the product of two large primes or computing discrete logarithms
[citation needed]
.
Note that "secure" here has a precise mathematical meaning, and there are multiple different
(meaningful) definitions of what it means for an encryption scheme to be secure. The "right"
definition depends on the context in which the scheme will be deployed.
In contrast to the one-time pad, no public-key encryption scheme can be secure against
eavesdroppers with unlimited computational power. Proofs of security therefore hold with respect to
computationally-limited adversaries, and give guarantees (relative to a particular mathematical
assumption) of the form "the scheme cannot be broken using a desktop computer in 1000 years".
The most obvious application of a public key encryption system is confidentiality; a message which
a sender encrypts using the recipient's public key can only be decrypted by the recipient's paired
private key.
Public-key digital signature algorithms can be used for sender authentication and non-repudiation.
For instance, a user can encrypt a message with his own private key and send it. If another user can
successfully decrypt it using the corresponding public key, this provides assurance that the first user
(and no other) sent it. In practice, a cryptographic hash value of the message is calculated, encrypted
with the private key and sent along with the message (resulting in a cryptographic signature of the
message). The receiver can then verify message integrity and origin by calculating the hash value of
the received message and comparing it against the decoded signature (the original hash). If the hash
from the sender and the hash on the receiver side do not match, then the received message is not
identical to the message which the sender "signed", or the sender's identity is wrong.
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To achieve authentication, non-repudiation, and confidentiality, the sender would first encrypt the
message using his private key, then a second encryption is performed using the recipient's public
key.
Fig 5.1.1 Public keys
5.1.2 TRUST BASED ARCHITECTURE FOR PERVASIVE SYSTEMS
Simple public key infrastructure (SPKI, pronounced spoo-key) was born out of a joint effort to
overcome the overcomplication and scalability problems of traditional X.509 public key
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infrastructure. It is specified in two Internet Engineering Task Force (IETF) Request For Comments
(RFC) specifications -- RFC 2692 and RFC 2693 -- from the IETF SPKI working group. These two
RFCs are at the EXPERIMENTAL maturity level of the IETF's RFC status. The SPKI specification
defines an authorization certificate format, providing for the delineation of privileges, rights or other
such attributes (called authorizations) and binding them to a public key. In 1996, SPKI was merged
with Simple Distributed Security Infrastructure.
History and Overview
The original SPKI had identified principals only as public keys but allowed binding authorizations to
those keys and delegation of authorization from one key to another. The encoding used was
attribute:value pairing, similar to RFC 822 headers.
The original SDSI bound local names (of individuals or groups) to public keys (or other names), but
carried authorization only in Access Control Lists (ACLs) and did not allow for delegation of
subsets of a principal's authorization. The encoding used was standard S-expression.
The combined SPKI/SDSI allows the naming of principals, creation of named groups of principals
and the delegation of rights or other attributes from one principal to another. It includes a language
for expression of authorization - a language that includes a definition of "intersection" of
authorizations. It also includes the notion of threshold subject - a construct granting authorizations
(or delegations) only when K of N of the listed subjects concur (in a request for access or a
delegation of rights). SPKI/SDSI uses S-expression encoding, but specifies a binary form that is
extremely easy to parse - an LR(0) grammar - called Canonical S-expressions.
SPKI/SDSI does not define a role for a commercial Certificate Authority (CA). In fact, one premise
behind SPKI is that a commercial CA serves no useful purpose. As a result of that, SPKI/SDSI is
deployed primarily in closed solutions and in demonstration projects of academic interest. Another
side-effect of this design element is that it is difficult to monetize SPKI/SDSI by itself. It can be a
component of some other product, but there is no business case for developing SPKI/SDSI tools and
services except as part of some other product.
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The most prominent general deployments of SPKI/SDSI are E-speak, a middleware product from HP
that used SPKI/SDSI for access control of web methods, and UPnP Security, that uses an XML
dialect of SPKI/SDSI for access control of web methods, delegation of rights among network
participants, etc.
Fig 5.1.2 Trust in pervasive computing environments.
John requests Susan for access to various services. Susan sends back a delegation certificate that
John sends to the security agent. The security verifies the certificate and, because Susan is trusted,
allows John to access the services.
6. FUTURISTIC PROPOSITIONS
Top 12 Areas for Innovation through 2025 : :Trend three: Pervasive Computing Washington
DC, December 17â€The DC-based research and consulting firm Social Technologies has
released a series of 12 briefs that shed light on the top areas for technology innovation through
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2025. The third innovation brief in the series, Pervasive Computing, was written by futurist
Christopher Kent, who explains that soon we will live in a world where everything is connected.
Pervasive computing will tie together billions of smart devices to expand connectivity and
human capabilities over a wider area than ever before, he says. This hyper-connectivity will
shift the Internet from the concept of being Ëœanytime, anyplace connectivity for anyone,â„¢ to
Ëœconnectivity for anything.â„¢ Hereâ„¢s why.
Drivers of the new technology Pervasive computing, or ubiquitous computing as it is often
called, is the idea that eventually almost every device or object in our lives will be both smart
and networked, Kent says. This will give rise to Ëœthe Internet of thingsâ„¢ that will push current
trends toward the convergence of computing, Internet access, voice communications, and
televisionâ€blurring categories of information and communication technology products and
services.
Consumers will be the beneficiaries, Kent believes, for they will have access to devices of
various sizes serving different needs, and devices with multifunctional capabilities. Of course,
this assumes the spread of wireless broadband communications.
Other technologies are sure to emerge to support new capabilities, he says, including:
smartphones, ambient user interfaces, set-top media boxes, fixed and wireless networking
technologies, and telematics.
6.1 CHALLENGES AHEAD
Although computing is growing in many areas, Kent points out significant obstacles will have to be
overcome before pervasive computing becomes real. Consider these:
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Network security. The more things are linked, the easier it becomes for outsiders to
access critical systems and information. For example, divorce attorneys on the east coast
of the US have begun to subpoena EZpass automatic toll records in order to discredit
philandering spouses.
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Managing increased data flows. Sensors, RFID tags, mobile networks, and wireless
networks all use different protocols for communicating, creating a technological Tower
of Babel. A unifying protocol would boost the developmentâ€but to date there is none,
and so far the benefits of proprietary protocols outweigh the need for open systems.
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Costs. Most sensor networks are still being assembled from off-the-shelf parts, making
them relatively expensive. Network analysts state that for sensor networks to be
economical, the cost of sensor assembly needs to drop to $20 from the current $100.
6.2 CONCEPTS AND TECHNOLOGY FOR THE FUTURE
Pervasive computing is the next generation computing environments with information &
communication technology everywhere, for everyone, at all times.
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Information and communication technology will be an integrated part of our environments: from
toys, milk cartons and desktops to cars, factories and whole city areas - with integrated processors,
sensors, and actuators connected via high-speed networks and combined with new visualisation
devices ranging from projections directly into the eye to large panorama displays.
The Centre for Pervasive Computing contributes to the development of
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new concepts, technologies, products and services
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innovative interaction between universities and companies
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a strong future basis for educating IT specialists.
Pervasive computing goes beyond the traditional user interfaces, on the one hand imploding them
into small devices and appliances, and on the other hand exploding them onto large scale walls,
buildings and furniture.
The activities in the centre are based on competencies from a broad spectrum of Research Areas of
relevance for pervasive computing. Most of the work in the centre is organised as Research Projects
involving both companies and universities.
6.3 RESEARCH AREAS
The activities in the centre are based on competencies from a broad spectrum of research areas
supporting pervasive computing. Currently, the centre involves the following research areas:
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Ambient Intelligence with Tangible Objects
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Center for Advanced Visualization and Interaction - CAVI
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Center for Pervasive Healthcare
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Computer Supported Cooperative Work
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Database Technology
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Design Anthropology
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Embedded Systems - Embodied Agents
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Interactive Workspace
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Mobile Systems and Wireless Communication
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Modelling and Validation of Distributed Systems
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New Ways of Working
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Object Technology
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Sound as Media
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Tangible User Interaction
Some research areas are well-established, like Object Technology, some are emerging. Each area is
headed by a research manager.
Most of the work in the centre is organised as research projects involving both companies and
universities. Many projects cut across research areas.
6.4 RESEARCH PROJECTS
Most of the work in the Centre for Pervasive Computing is organised around joint research projects
involving both companies and universities. Many projects cut across research areas and practically
all projects involve several traditional research disciplines.
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In this way, the joint research projects of the centre support sharing of knowledge across research
disciplines as well as between university-based research groups and partners from private enterprise.
List of projects currently associated Centre for Pervasive Computing.
It in the work place
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A Knowledge Company
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Common Information Spaces
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Interactive Room Appliances in the Flexible Office
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Nomadic Work and the Flexible Office
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Virtual Project Room - DMM
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WorkSPACE
Object Technology
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Distributed Objects in Embedded Systems
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Integrating the BETA Language with Eclipse
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Jini as a foundation technology for pervasive system
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Knight
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Objects in Appliances
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Object oriented language interoperability
7. CONCLUSION
We stand at the beginning of yet another epoc in computers. The battle lines are drawn for the heart
and soul of this new infrastructure. Let the games begin. The trends in pervasive computing are
increasing the diversity and heterogeneity of networks and their constituent devices Pervasive
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computing is expected to bring an explosion in the number of devices in our local environments.
This paper presents a vision of a future computing landscape characterized by the ubiquity of
computing devices, the autonomy, dynamicity and the heterogeneity of system components.
Sociologically, ubiquitous computing may mean the decline of the computer addict. In the 1910's
and 1920's many people "hacked" on crystal sets to take advantage of the new high tech world of
radio. Now crystal-and-cat's whisker receivers are rare, because radios are ubiquitous. In addition,
embodied virtuality will bring computers to the presidents of industries and countries for nearly the
first time. Computer access will penetrate all groups in society.
Most important, ubiquitous computers will help overcome the problem of information overload.
There is more information available at our fingertips during a walk in the woods than in any
computer system, yet people find a walk among trees relaxing and computers frustrating. Machines
that fit the human environment, instead of forcing humans to enter theirs, will make using a
computer as refreshing as taking a walk in the woods.
8. REFERENCES
? http://researchweb.watson.ibmjournal/sj/384/ark.html
? http://sentilla
? http://percom
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? http://youtubewatch?v=KsKne-fw-X0
? http://computerportal/site/ieeecs
