This document provides an introduction to the Internet of Things (IoT). It defines IoT according to various organizations and discusses the trends, enablers, and drivers that have led to the rise of IoT. It also provides an overview of key IoT technologies and components as well as example application areas. Finally, it discusses examples of IoT devices including sensors, Raspberry Pi, and Arduino and how they can be used to build IoT solutions.

1. Introduction to the Internet of
Things (IoT)
John Soldatos, PhD
(jsol@ait.gr; john.Soldatos@gmail.com)

2. Overview: Contents
What is the Internet of
Things?
• Definitions
• Motivation,
Enablers, and Drivers
Overview of Internet
of Things Technologies
and Applications
• IoT Components
• IoT Application areas
Examples of IoT
Devices
• Sensors
• Raspberry Pi &
Arduino

3. IoT Definitions
UN (2005)
“A new era of ubiquity is
coming where humans may
become the minority as
generators and receivers of
traffic and changes brought
about by the Internet will
be dwarfed by those
prompted by the
networking of everyday
objects”
ITU
“From anytime, anyplace
connectivity for anyone, we
will now have connectivity
for anything”
EU
‘‘Things having identities
and virtual personalities
operating in smart spaces
using intelligent interfaces
to connect and
communicate within social,
environmental, and user
contexts”

4. Trends in Computing
Source: Mark Weisser
(http://www.ubiq.com),
Computer Science Lab at
Xerox PARC

5. Emergence & Rise of IoT

6. Why IoT: Proliferation of Sensors &
Connected Devices

7. Why IoT: Things are getting connected
7

8. People connect to Things
Motion sensor
Motion sensor
Motion sensor
ECG sensor
Internet

9. Things connect to Things
9
- Complex and heterogeneous
resources and networks
MN: Mobile Node

10. Some IoT (Intro) Videos
• https://www.youtube.com/watch?v=KIMYZE2Ma6IEuropean Commission: Internet-of-
Things
• http://www.youtube.com/watch?v=Q3ur8wzzhBUIntel IoT: What Does The Internet of
Things Mean?
• http://www.youtube.com/watch?v=B_hjAfPJeRACisco: How the Internet of Things Will
Change Everything—Including Ourselves
• http://www.youtube.com/watch?v=df9xAZZ-8zgIBM: Internet of Things
• https://www.youtube.com/watch?v=uMYQ6AnBK-cMicrosoft: The Internet of Your Things
• http://www.youtube.com/watch?v=QaTIt1C5R-MTEDxCIT: The Internet of Things

11. IoT vs. “Similar” Technologies
•USN (Ubiquitous Sensor Networks)
•M2M (Machine-to-Machine)
•IoE (Internet of Everything)
•CoT (Cloud of Things)
•WoT (Web of Things)
•CPS (Cyber Physical Systems)

12. IoT Technologies and Applications
IoTTechnologies
Sensors & Wireless Sensors
Networks (WSN)
Radio-Frequency-
Identification
Semantics &
Interoperability
IoT Cloud Integration
IoT Analytics & BigData
IoTApplications
Smart Cities & Communities
IoT in Healthcare
IoT in Manufacturing &
Logistics
IoT in Transport (e.g.,
Connected Car, Self-Driving
Car)
IoT in Smart Buildings (e.g.,
Facility Management)

13. Typical IoT Components
• Sensors/Actuators
• Communication between servers or server platforms
• Server/Middleware Platforms
• Data Analytics Engines
• Apps (iOS, Android, Web)
IoT-A Architecture Model (www.iot-a.eu/)
Source: Microsoft Blogs (blogs.msdn.microsoft.com)

14. Wireless Sensor Networks (WSN)
14
Sink
node
Gateway
Core network
e.g. InternetGateway
End-user
Computer services

15. IoT & Cloud Computing
Source: J. Gubbi et al. / Future Generation Computer Systems 29 (2013) 1645–1660

16. Elements of an IoT Deployment
16
Source: Datang Telecom Technology & Industry Group

17. IoT Application Areas
Source: J. Gubbi et al. / Future Generation Computer Systems 29 (2013) 1645–1660

18. IoT Perspectives & Visions
L. Atzori et al. / Computer Networks 54 (2010) 2787–2805

19. IoT Devices: Sensors
Sensor
• Provides usable output in response
to a specified measurement
• A sensor acquires a physical
parameter and converts it into a
signal suitable for processing (e.g.,
optical, electrical, mechanical)
Deployment and Applications
• Bodies, automobiles, airplanes,
cellular telephones, radios, chemical
plants, industrial plants, etc.
• Many other applications

20. IoT Devices: Sensors
Stimulus Type Signal/Quantity
Acoustic Wave (amplitude, phase, polarization), Spectrum, Wave
Velocity
Biological & Chemical Fluid Concentrations (Gas or Liquid)
Electric Charge, Voltage, Current, Electric Field (amplitude, phase,
polarization), Conductivity, Permittivity
Magnetic Magnetic Field (amplitude, phase, polarization), Flux,
Permeability
Optical Refractive Index, Reflectivity, Absorption
Thermal Temperature, Flux, Specific Heat, Thermal Conductivity
Mechanical Position, Velocity, Acceleration, Force, Strain, Stress,
Pressure, Torque

21. IoT Devices: Sensors & Actuators
Transducer
Sensor
Detects &
Measures a Signal
or Stimulus
Acquires
information from
the real world
Actuator
Generates Signal
or Stimulus
Real
World
Sensor
Actuator
Intelligent
Feedback
System
• Transducer:
• Converts a primary form of energy
into a signal with a different energy
form
• Energy form examples:
• Mechanical
• Thermal
• Electromagnetic
• Optical
• Chemical
• etc.

22. Sensor Examples (1)
Temperature sensors
• Temperature can be
measured through
pressure, volume,
electrical resistance, and
strain
• Applications: Buildings,
chemical process plants,
engines, appliances,
computers, etc.
Accelerometers
• Measures along one axis
and is insensitive to
orthogonal directions
• Applications: Vibrations,
blasts, impacts, shock
waves, air bags, washing
machines, heart
monitors, car alarms,
etc.
Light Sensors
• Composed of
photoconductor, such as
a photoresistor,
photodiode, or
phototransistor
• Applications: Cameras,
infrared detectors, and
ambient lighting
applications

23. Sensor Examples (2)
Ultrasonic sensors
• Used for position
measurements
• Sound waves emitted
are in the range of 2-13
MHz
• Sound Navigation And
Ranging (SONAR)
• Radio Detection And
Ranging (RADAR)
Photogate
• Used in counting
applications (e.g.,
motion period
identification)
• Records time at which
light is broken
• Includes infrared
transmitter and receiver
at opposite ends of the
sensor
CO2 Gas Sensor
• Measures gaseous CO2
levels in an environment
• Measures CO2 levels in
the range of 0-5000 ppm
(parts per million)
• Monitors infrared
radiation absorbed by
CO2 molecules

24. Sensor Selection Criteria
Economic
• Cost
• Availability
• Lifetime
• Etc.
Environmental
• Size
• Power
Consumption
• Interference &
Sensitivity
• Etc.
Sensor
Characteristics
• Sensitivity
• Range
• Stability
• Error
• Response Time

25. IoT Devices: Arduino
Overview
• Open-source electronics
prototyping platform
• Flexible & easy-to-use hardware
and software
• Typical Users: Artists, designers,
hobbyists
• Applications involving interactive
objects or environments
Benefits
• Microcontroller: Bridge between
cyber & physical worlds
• Balances functionality and ease
of use
• Low costs (e.g., starting from $35)
• Arduino C
Types
• Leonardo
• Due
• Micro
• LilyPad
• Esplora
• Uno

26. Arduino Programming (1)
•C++ based: A handful of new commands
•Programs are called “sketches”.
•Sketches need two functions:
• void setup( ): Runs first and once
• void loop( ): Runs over and over, until power is lost or a new sketch is loaded
• PIN = Global Variables

27. Arduino Programming (2)
• digitalWrite(pin, value): Sends a voltage level to the designated pin
• pinMode(pin, mode): Designates the specified pin for input or output
• digitalRead(pin): Reads the current voltage level from the designated pin
• Analog versions of above: analogRead's range is 0 to 1023
• Serial commands: print, println, write
• www.arduino.cc: Online support forum

28. Sensors & Shields
Sensors
• Can be both binary or a range
• Measure a range of values, vary their
resistance to reflect their detection
• Arduinos sense voltages, not
resistances
• Sensors that only vary their
resistances: Voltage divider to
provide the Arduino a voltage is
required
Shields
• Circuit boards that plug into the top
of an Arduino in order to enhance its
functionality
• Examples: Ethernet, GPS, Motor,
Prototype

29. Devices: Raspberry Pi
Raspberry (University of
Cambridge)
• Credit card sized PC: Plugs into a
TV or monitor
• Extensively used for IoT Education
• Typical Uses: Programming,
Electronic Projects, Office, HD
Videos Playback
• Cost: Approx. $35-$100
(depending on extras)

30. Raspberry Pi Components
Core
Raspberry Pi board
Prepared Operating System SD
Card
USB keyboard
Display (with HDMI, DVI, or
Composite input)
Power Supply
Extras
USB mouse
Internet connectivity: LAN cable
Powered USB Hub
Case
Programming
Languages
C
C++
Java
Scratch
Ruby
Any supported on ARM6

31. Raspberry Pi Sample IoT Projects
Simple
Programmable
Networked Sensor
Low-cost digital temperature and
humidity sensor integrated with
Raspberry Pi
https://github.com/jervine/rpi-
temp-humid-monitor
ThinkBox (IoT on
Raspberry Pi)
Software already installed &
configured: Graphical creation of
new applications from a simple
web browser
http://thethingbox.io/
Raspberry People
Counter
Motion Sensors wired to the GPIO
pins of Raspberry Pi
http://blog.ubidots.com/building-
a-people-counter-with-raspberry-
pi-and-ubidots