This document outlines key aspects of pervasive computing including:
1. It discusses the evolution of computing from mainframes to personal computers to the emerging era of pervasive computing.
2. It describes the architecture of pervasive computing including applications, middleware, intelligent computing, mobile computing, context-awareness and affective computing components.
3. It examines wireless communication technologies used in pervasive computing like Zigbee, Bluetooth, WiFi and discusses security issues with vulnerabilities in these wireless systems including denial of service attacks, eavesdropping and message injection.
2. Outline
I. Overview of Pervasive Computing
II. Architecture
III. Wireless Communication Technologies in Pervasive
Computing and Security Issues
IV. Wireless Vulnerabilities
V. Conclusion
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3. Pervasive Computing Overview
“Ubiquitous computing names the third wave in computing, just
now beginning. First were mainframes, each shared by lots of
people. Now we are in the personal computing era, person and
machine staring uneasily at each other across the desktop. Next
comes ubiquitous computing, or the age of calm
technology, when technology recedes into the background of our
lives.”
“The Computer for the 21st Century”
- September, 1991
Mark D. Weiser (July 23, 1952 – April 27, 1999)3
4. Pervasive Computing Overview
Development of computing technologies:
1st wave : Mainframe computing era
2nd wave : Personal computing era
3rd wave : Pervasive computing era
(initially called ubiquitous computing)
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5. What is Pervasive Computing
Integration of Information and Communications
Technology (ICT) into people’s lives and
environments, made possible by the growing availability
of microprocessors with inbuilt communication
facilities.
Goals:
People Oriented
Implicitly use of computers
People will focus on task, not tool
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6. Pervasive Computing Components
Three converging areas of ICT components:
Computing devices: communicate with each other and
act intelligently
Sensors: input devices
Processors: interpret and analyze data
Actuators: output devices
Communications: serve pervasive computing applications
Ex. Zigbee, Bluetooth, WiFi, Wimax /LTE /3G /4G …
User Interfaces: point of contact between ICT and human
Active: Users overtly control PC technologies and devices
Passive: PC covertly control in the background
Coercive: both Active and Passive
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7. Architecture
Application
Middleware and Security Interface
Various applications such as
Smart Room, Intelligent
Intelligent Computing
Mobile Computing
Navigation… can be built and
Context-Aware used
Affective Computing
Embedded Operating System
Hardware
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8. Architecture
Application Not only:
Middleware and Security Interface Heterogeneity
Scalability
Intelligent Computing
Mobile Computing Programming interface
Context-Aware
But also:
Affective Computing Service Discovery
Context-aware
Embedded Operating System
Hardware
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10. Architecture
Application
Middleware and Security Interface
An important aspect of the
Intelligent Computing
Mobile Computing difference between pervasive
computing and desktop
Context-Aware computing
Affective Computing
Embedded Operating System
Hardware
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11. Architecture
Mobile Computing:
•Automatic configuration, dynamic addressing and tracking system
•Free switch between heterogeneous networks
Affective Computing is the computing that relates to, arises
from, or deliberately influences emotions.
– Rosalind W. Picard
•computer science, sensor technology, psychology, physiology
•Key technologies: face recognitions, emotional signal
measurements and analysis
Context-aware Computing: senses environment context and
human context changes.
Key technologies: Location awareness, activities recognition
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12. Architecture
Application Hardware:
Middleware and Security Interface Fast processing speed
Small size
Intelligent Computing
Mobile Computing
Context-Aware Embedded Operating
System:
Affective Computing
Real-time services
Rational allocation
Embedded Operating System memories
Hardware
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13. Architecture
Structure of Embedded Operating System and Hardware
Network
Sensors I/O Device
Interface
Real-time Embedded Operating System
Pervasive Computing Hardware
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14. Wireless Communication
Many existing and emerging wireless technologies
serve in Pervasive Computing:
•Zigbee and Bluetooth - sensors and actuators - low
energy consumption, short distances (up to 10 meters)
•Wi-Fi - devices - middle ranges (several hundreds of meters)
•Wimax /LTE /3G /4G - a home gateway to Internet - long
ranges (several to tens of kilometres)
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15. Security Issues
Common vulnerabilities existing in wireless technologies:
Physical jamming
Passive eavesdropping and traffic analysis
Message injection and active eavesdropping
Message deletion and interception
Insider attacks to breach data confidentiality
Denial of service (DoS) attacks
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16. Security Issues
Various types of Attack to a Pervasive Computing can:
Compromise users’ data,
Crash an entire system
Render services unavailable
Potentially lead to the loss of property
Harm users and even lives
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17. Wireless Vulnerabilities
Wi-Fi MAC Protocol Attacks
Carrier Sense Multiple Access with Collision Avoidance
(CSMA/CA)
DoS attack: Clear Channel Assessment-Jamming
Virtual carrier sense
DoS attack: Repeat forged RTS/CTS messages with large
NAV leading network slowdown
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20. Wireless Vulnerabilities
Wi-Fi Security Protocol Attacks
Pre-Robust Security Network Association (Pre-RSNA):
security mechanisms in the IEEE 802.11-1997
Attacks on Wired Equivalent Privacy(WEP):
Shared Key management – key can be easily obtained from the
attackers
Weak RC4 encryption implementation – key can be easily broken
by the brute force attack
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21. Wireless Vulnerabilities
Robust Security Network Association (RSNA): security
mechanisms in the IEEE 802.11-2007,
consisting of 3 security algorithms:
Data confidentiality and integrity protocols
RSNA security association management
key management procedures
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22. Wireless Vulnerabilities
Attacks on RSNA
•Security level rollback attack: “Pre-RSNA only” beacons to force
the network to use WEP
•EAP attack: forged association requests - disconnect legitimate
users.
•Four-way handshake DoS attack: forged first unauthenticated
message - parallel incomplete Handshakes - exhaust queue
space
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23. Wireless Vulnerabilities
Attacks on RSNA (Cont.)
•RSN IE poisoning: fake beacons - fail at stage 3
•Reflection attack against four-way handshake: transmitted
data sent back to originator .
•Dos attack against TKIP: intercepted and modified packet - AP
and the client suspend their communication
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24. Conclusion
Confidentiality, Integrity, and Availability (CIA) are
essential to pervasive computing applications since
sensitive and real-time information may flow over any type
of wireless links
Many challenges and attacks have been proved. Each
operation and policy should be carefully examined against
any possible attacks.
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25. Reference
Liu, Y. & Li, F., PCA: A Reference Architecture for Pervasive Computing, 2006 1 st
International Symposium on Pervasive Computing and Applications, IEEE
04079121
Zhou, B, Marshall, A. & Lee, T. H., Wireless Security Issues in pervasive
computing, 2010 Fourth International Conference on Genetic and Evolutionary
Computing, IEEE 05715481
2006, Pervasive Computing, Parliamentary Office of Science and Technology
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First Wave - Mainframe computing: one computer shared by many people, via workstations.Second Wave - Personal computing: one computer used by one person, requiring a conscious interaction. Users largely bound to desktop.Third Wave – Pervasive (initially called ubiquitous) computing: one person, many computers. Millions of computers embedded in the environment, allowing technology to recede into the background.
Integrate between people’s lives and env. and make it available for the growth in number of microprocessors connected together using inbuilt (originally equipped with) communication technology such as wire or wireless technology and Internet.Goal of pervasive computing is the realization of computing people-oriented and ubiquitous, making the computer disappear from the eyes of the people, and people can't feel the presence of computer , so that people can only focus on the task rather than the tool - computer itself
actuators: output devices that respond to processed information by altering the environment via electronic or mechanical means. Zigbee and Bluetooth can be used to connect sensors and actuators with low energy consumption in short distances (up to 10 meters)Wi-Fi can be used to connect devices in middle ranges (several hundreds of meters);Wimax /LTE /3G /4G can be used to connect a home gateway to Internet in long ranges (several to tens of kilometres)
The function of services discovery is the faculty of middleware dynamic finding service. Once middleware found on service, it will start banding services and the corresponding procedures. It enables devices and services to properly discover, configure, and communicate with each other
Context-aware computing : For example: a context aware mobile phone may know that it is currently in the meeting room, and that the user has sat down. The phone may conclude that the user is currently in a meeting and reject any unimportant calls. - location awareness and activity recognition
Physical jamming: an adversary generates strong noises to prevent legitimate communications
EAP : Extensible Authentication Protocolsupports multiple authentication methods, such as token cards, one-time passwords, certificates, public key authentication and smart cards. IEEE 802.1x specifies how EAP should be encapsulated in LAN frames.
temporal key identity protocol (TKIP)When TKIP is used, a 20-bit message integrity check (MIC) is computed. Theoretically, it takes 2 minutes to crack MIC by brute force at 11 Mbps data rate. A countermeasure against this vulnerability is implemented with the temporal key identity protocol (TKIP): If two MIC failures are logged within one minute, communications are suspended for 60 seconds (this makes the brute force crack take 6 months). However, an attacker can attack against this countermeasure by intercepting a packet, modifying it so as to make the receiving station unable to calculate the correct MIC, and sending it again and again. This will make the AP and the client suspend their communication.