410445B Elective-II: l Pervasive Computing

l Teaching Schemel Lectures: 3 Hrs/Week

l Examination Schemel In semester Assessment: 30l End Semester Assessment : 70

l Course Objectives:l To introduce pervasive computing abilities.l To  introduce  tools  and  techniques  used  while 

solving problems using pervasive computing.l To  study  algorithmic  examples  in  distributed, 

concurrent and parallel environments.l Course Outcomes:

l To solve problem pervasive computing abilities.l To  solve  problems  for  multi­core  or  distributed, 

concurrent/Parallel environments.

l Text Books:l 1.  Stefan  Poslad,  Ubiquitous  Computing,  Smart 

devices, environment and interaction, Wiley.

l 2. Frank Adelstein, Sandeep Gupta, Golden Richard III, Loren Schwiebert, Fundamentals of Mobile and Pervasive Computing, Tata McGraw Hills

l Reference Books:l 1.  Jochen  Burkhardt,  Horst  Henn,  Stefan  Hepper, 

Klaus  Rindtorff,  Thomas  Schaeck,  Pervasive Computing, Pearson, Eighteenth Impression, 2014.

Pervasive Computing Introduction

Pervasive Computing Era

What is pervasive computing?

• The word Pervasive or ubiquitious means “Existing Everywhere”

• An environment in which people interact with embedded (and mostly invisible) computers (processors) and in which networked devices are aware of their surroundings and peers and are able to provide services or use services from peers effectively.

Characteristics of Pervasive Computing

• Physical Integration• Integration between the computing nodes and physical

world.• Eg. A whiteboard that record what's on.

• Instantaneous Interoperation• Devices interoperates spontaneously in changing

environments• Eg. A device change its partners as it moves from one

region to another.

Principles of Pervasive Computing

Decentralisation

Diversification

Connectivity

Simplicity

Examples

Pervasive Computing Environments

Handheld Devices

Pervasive computing devices communicate and take actions.

Laptops

Berkeley Motes

Network camera

Goals of Pervasive (Ubiquitous) Computing

• Ultimate goal:–Invisible technology–Integration of virtual and physical worlds–Throughout desks, rooms, buildings, and life–Take the data out of environment, leaving

behind just an enhanced ability to act

What is a distributed system?&

What are the design goals?

Transparency in a Distributed System

Openness in Distributed Systems

An open distributed system Offers services according to standard rules that describe

syntax and semantics of the services Can interact with services from other open systems,

irrespective of the underlying environment

Examples In computer networks, standard rules govern the format,

contents and meaning of messages sent and received

So, what is Scalability?

Hardware Concepts

1.6

Basic organizations and memories in distributed computer systems

What is Distributed Computing/System?

• Distributed computing– A field of computing science that studies distributed system.– The use of distributed systems to solve computational problems.

What is Distributed Computing/System?

• Distributed program– A computing program that runs in a distributed

system• Distributed programming

– The process of writing distributed program

What is Distributed Computing/System?

• Common properties– Fault tolerance

• When one or some nodes fails, the whole system can still work fine except performance.• Need to check the status of each node

– Each node play partial role• Each computer has only a limited, incomplete view of the system.

– Resource sharing• Each user can share the computing power and storage resource in the system with other

users

– Load Sharing• Dispatching several tasks to each nodes can help share loading to the whole system.

– Easy to expand• We expect to use few time when adding nodes. Hope to spend no time • if possible.

Why Distributed Computing?

• The nature of application• Performance

– Computing intensive• The task could consume a lot of time on computing.

– Data intensive• The task that deals with a large size of files. • For example, Facebook.

• Robustness– No SPOF (Single Point Of Failure)– Other nodes can execute the same task executed on

failed node.

Common Architectures

• Communicate and coordinate works among concurrent processes– Processes communicate by sending/receiving

messages– Synchronous/Asynchronous

Common Architectures

• Master/Slave architecture– Master/slave is a model of

communication where one device or process has unidirectional control over one or more other devices• Database replication

– Source database can be treated as a master and the destination database can treated as a slave.

• Client-server– web browsers and web servers

Common Architectures

• Data-centric architecture– Using a standard, general-purpose relational

database management system ; customized in-memory or file-based data structures and access method

– Stored procedures ; logic running in middle-tier application servers

– Shared databases as the basis for communicating between parallel processes ; direct inter-process communication via message passing function

l What Is Mobile Computing?

l What is computing? Operation of computers.

l What is the mobile? That someone /something can move or be moved easily and quickly from place to place .

l What is mobile computing? Users with portable computers still have network connections while they move

l What Is Mobile Computing? (Cont.)A simple definition could be:l Mobile Computing is using a computer (of one kind or

another) while on the move l Another definition could be:l Mobile Computing is when a (work) process is moved from

a normal fixed position to a more dynamic position. l A third definition could be:l Mobile Computing is when a work process is carried out

somewhere where it was not previously possibleMobile Computing is an umbrella term used to describe technologies that enable people to access network services anyplace, anytime, and anywhere. .

l Comparison to Wired Net.l Wired Networksl high bandwidthl low bandwidth variabilityl can listen on wirel high power machinesl high resource machinesl need physical access

(security)l low delay

l Mobile Networks1.low bandwidth2.high bandwidth variability3.hidden terminal problem4.low power machines5.low resource machines6.need proximity (close relationship

with time, space etc.)7.higher delay

l Applications of Mobile Computing

l For Estate Agents l In courts l In companies l Stock Information Collection/Control l Taxi/Truck Dispatch l Electronic Mail/Paging

Wearable Computing

>>Wearable Computer Implementation

Overall System Block Diagram :

WirelessNetwork

Input Device Display Device

Video Camera

Low Power Indicator Power Supply

Com port VGA outFram

e g

rab

ber

Netw

ork

card

Parallel port Back plane

Main Unit

>>Wearable Computer Implementation>>Input Device

speech recognizer keyboard alternative including chording keyboards and special purpose

keyboards mouse alternatives including trackballs, joysticks tab alternatives including buttons, dial eye trackers head trackers pen gesturing bar code reader video capture devices, microphones, GPS locators other exotic devices such as skin sensors

>>Wearable Computer Implementation>>Input Device

Wireless Finger Ring

Detection of finger-tip typingWireless LinkBlock DiagramsChording METHOD

>>Wearable Computer Implementation>>Output Device

head mounted displays (HMDs)flat panels, text to speechtactile outputnon speech auditory outputpaper and olfactory output (scent)

>>Wearable Computer Implementation>>Output Device

Augmented Reality

Typical Augmented Reality System

Display Technologies in Augmented Reality

>>Wearable Computer Networking

General requirements

Short-rangedSimple in designLow power consumptionSelf-configurationRestricted to the userSecurity

Security requirements

PrivacyData ConfidentialityData integrityAccess ControlAvailabilitySource Authentication

• Modelling the Key Ubiquitous Computing Properties

•

Ubiquitous computing: smart devices, environments and interaction 40

UbiCom: Weiser’s 3 Internal System Properties

3 main properties for UbiCom Systems were proposed by Weiser (1991)1.Computers need to be networked, distributed and

transparently accessible

2.Computer Interaction with Humans needs to be more hidden

3.Computers need to be aware of environment context– In order to optimise their operation in their physical &

human environment.

Ubiquitous computing: smart devices, environments and interaction 41

Devices: Extended set of Internal System Properties

To which two additional properties are added:1.Computers can operate autonomously, without human intervention, be

self-governed2.Computers can handle a multiplicity of dynamic actions and interactions,

governed by intelligent decision-making and intelligent organisational interaction. This entails some form of artificial intelligence.

Ubiquitous computing: smart devices, environments and interaction 42

l Five main properties for UbiCom

43Ubiquitous computing: smart devices, environments and interaction

l UbiCom System Properties: 1. Distributed

• Networked ICT Devices• Pervasive compuuters are network computers.• They offer that can be locally and remotely accessed.

• Transparency • Access is hidden, integrated into environments

• Openness• Dynamically discover new externel services and to

access them.• It introduces complexity & reduces availability. • When one function is active, others may need to be

deactivated.

Ubiquitous computing: smart devices, environments and interaction 44

Internal System Properties: 2. iHCI

• Concept of calm / disappearing computer has several dimensions

• Implicit (iHCI) versus Explicit HCI• Embodied Virtuality as opposite of VR (people in virtual world)

Ubiquitous computing: smart devices, environments and interaction 45