Internet of Things:
Architecture, Challenges &
Applications
Evolution in Computing
Pre Computers Wired Computing Wireless Web of World
Era Era Computing Era Era
H2H H2M H2M M2M
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Evolution in IoT
FIGURE – Evolution of the Internet of Things [1]
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Definition: IoT
● The Internet of Things (IoT) is the network of physical objects or
"things" embedded with electronics, software, sensors, and
network connectivity, which enables these objects to collect and
exchange data.
● Internet of Things refers to the concept that the Internet is no
longer just a global network for people to communicate with one
another using computers, but it is also a platform for devices to
communicate electronically with the world around them.”
--Center for Data and Innovation
A world of intelligent, adaptive, self organized sensors, actuators, other devices and systems
that use various network technologies to connect each and every objects of physical world to
web of world.
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Why IoT?
● We want to receive
more data
● We want to control
stuff
● We want to
automate
● We want to make
things faster
Image from http://smartdatacollective.com/rick-delgado/285576/scary-security-
concerns-internet-things
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Fundamental Components of IoT
Many people mistakenly think of IoT as an independent
technology.
Interestingly internet of things is being enabled by the
presence of other independent technologies which make
fundamental components of IoT.
These components are:
Hardware : Making physical objects responsive and giving
them capability to retrieve data and respond to instructions
Software : Enabling the data collection, storage, processing,
manipulating and instructing
Communication Interface : Most important of all is the
communication infrastructure which consists of protocols and
technologies which enable two physical objects to exchange
data
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Digital Control system: The core part of IoT
An embedded is an electronic/electro mechanical system designed to
perform a specific function and is a combination of hardware and
software.
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Application of Digital control
Systems
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Let’s Look at Few Examples
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A scientific calculator
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3D Model Printer
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Unmanned Drone
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Signal Analyzer
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[Source: Postscape - http://postscapes.com/what-exactly-is-the-internet-of-things-infographic ]
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Examples
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Examples
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Examples
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Example: A Smart Home Scenario
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Example: Efficient Waste Management
in Smart Cities
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Example: Shopping
2. When shopping in the market, the goods will introduce
themselves.
1. When entering the doors, scanners will identify the tags
on her clothing.
4. When paying for the goods, the microchip of the credit
card will communicate with checkout reader.
3. When moving the goods, the reader will tell the staff to put
a new one.
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Applications
Image from https://inventrom.wordpress.com/2014/11/27/the-
thing-in-internet-of-things/
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Figure- Projected market share of dominant IoT applications by 2025 [2]
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IoT Architecture
FIGURE – Three Layer Architecture [3]
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IoT Architecture [cont’d]
FIGURE – Four Layer Architecture [4]
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IoT Architecture [cont’d]
FIGURE – Five Layer Architecture [5]
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IoT Architecture [cont’d]
FIGURE – The IoT architecture. (a) Three-layer. (b) Middle-ware based.
(c) SOA based. (d) Five-layer [6]
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46 Figure- IoT-related technology [7]
Figure- Technologies associated with IoT [7]
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IoT Connectivity
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Sensors
Sensing the Environment
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Sensors
● A sensor is a device that detects and responds to some type of input
from the physical environment and converts it into an electrical signal
that can be further processed.
● The specific input could be light, heat, motion, moisture, pressure, or
any one of a great number of other environmental phenomena.
● The nature of the electrical signal provided by a sensor depends on the
kind of sensor and how much information it needs to transmit.
● Some sensors (such as Photoresistors and Piezo knock sensors) are
constructed from a substance that alters their electrical properties in
response to physical change.
● Others are sophisticated electronic modules that use their own
microcontroller to process information before passing the signal to other
embedded system.
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Sensors
● Measure values
● Send raw data
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Methods to relay information
● Sensors may use any of the following methods to relay signal
or information to other control systems:
1. Digital On/Off
2. Analog
3. Pulse Width
4. Serial
5. Synchronous Protocols: I2C and SPI
I2C is half duplex communication and SPI is full duplex
communication
Digital On/Off Sensors
Digital sensors are more straight forward than Analog
No matter what the sensor is, there are only two settings:
O n and Off
Signal is always either H I G H (On) or LOW (Off)
Voltage sign al for H IG H will be a little less tha n 5V on
your Uno
Voltage signal for LOW will be 0V on most systems
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Digital On/Off Sensors
Motion Sensor
Door Entry Sensor
Capacitive Touch Sensor
Smoke Sensor
Fire Sensor
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Digital On/Off Sensors
Sensor ON
Sensor OFF
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Analog Sensors
Analog sensors utilize continuous values to represent
information for input
For an analog sensor signal to be processed, or used in
digital equipment, it needs to be converted to a digital
signal, using a n analog-to-digital converter.
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Analog Sensors
Smoke Sensor
Joystick Sensor
Flex Sensor
Light Sensor Temperature Sensor
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Analog LDR Sensor
More Ambient Light
= LED OFF
Less Ambient Light
= LED ON
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Analog Temperature Sensor
Temperature = 19 *C
Fan OFF
Temperature = 21 *C
Fan ON
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Pulse Width
● Sensors provide data using pulse duration proportional to the
distance value.
Ultrasonic Sensor
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Serial Communication
Method used to transfer data between two
devices.
Data passes between the computer and Embedded
device through the USB cable or Serial connections.
Data is transmitted as zeros (‘0’) and ones (‘1’)
sequentially.
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Serial Communication
Camera using RS232 Fingerprint Scanner using UART
GPS using UART
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Synchronous: I2C and SPI
● I2C is half duplex communication and SPI is full duplex communication
● Sensors can provide synchronous data over protocols such as I2C and
SPI.
● Inter-Integrated Circuit
● I2C or IIC (Inter-Integrated Circuit) is a simple bidirectional serial interface,
which requires only 2 signal lines for data transfer.
● Serial Peripheral Interface
● SPI is a synchronous serial data protocol used by microcontrollers for
communicating with one or more peripheral devices quickly over short
distances.
● It can also be used for communication between two microcontrollers or
between sensors and microcontrollers.
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Synchronous: I2C
Wii Nunchuk using I2C
Digital Compass using I2C
Temperature Sensor (TMP75) using I2C
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Synchronous: SPI
Barometric Pressure Sensor using SPI
Inertial Measurement Unit with GPS
using SPI
Light Module Sensor using SPI
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Devices
Operating on the Environment
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Devices
● In context of IoT, devices are classified into:
1. Actuators
Those devices which perform some controlling
mechanism thorough motion are termed as Actuators
2. Node System
Those devices which perform decision making tasks,
relays signals and controls actuators.
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Hardware
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Arduino
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Arduino
● It's an open-source physical computing platform based on a
simple microcontroller board, and a development environment
for writing software for the board.
● Arduino can be used to develop interactive objects, taking inputs
from a variety of switches or sensors, and controlling a variety of
lights, motors, and other physical outputs.
● Features:
1. Inexpensive
2. Cross-platform
3. Simple, clear programming environment
4. Open source and extensible software
5. Open source and extensible hardware
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Arduino DevelopmUeSn
B t Board
PWR IN (to Computer)
RESET
SCL\SDA
(I2C Bus)
POWER
5V / 3.3V / GND
Digital I\O
PWM(3, 5, 6, 9, 10, 11)
Analog
INPUTS
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Different Arduino Boards
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Different Arduino Shields
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Connecting Arduino to Internet
using Ethernet Shield
Ethernet Shield
Ethernet Shield stacked
over Arduino
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Connecting Arduino to Internet
using WiFi Shield
WiFi Shield
WiFi Shield stacked
over Arduino
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Developing WSN using Arduino
Wireless Sensor Network
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Using Arduino as Nodes
Nodes communicate with Gateway
using wireless modules
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Arduino Yún
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Arduino Yun
● The Arduino Yún has the same footprint as an Arduino Uno but
combines an ATmega32U4 microcontroller and a Linux system based
on the Atheros AR9331 chipset.
● It combines the power of Linux with the ease of use of Arduino.
● The board has built-in Ethernet and WiFi support
● The YÚN is a compact solution for a wider range of possibilities with
respect to its siblings, and it’s a step forward in the Internet of Things.
● The main advantages of having Linux on board are:
● a wide range of user-space application
(servers, clients, scripting, …)
● a wide range of drivers, mainly for USB devices
(webcams, user interfaces, …)
● ready to use file system management
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Arduino Yun Board
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Raspberry Pi
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Raspberry Pi
● The Raspberry Pi is a low cost, credit-card sized computer that plugs
into a computer monitor or TV, and uses a standard keyboard and
mouse.
● It is a capable little device that enables people of all ages to explore
computing, and to learn how to program in languages like Scratch and
Python.
● It’s capable of doing everything you’d expect a desktop computer to do
● Browsing the internet
● Playing high-definition video
● Making spreadsheets ● Word-processing
● Playing games.
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Why the name Raspberry Pi?
● The founders wanted a fruit name for nostalgia and
● Pi comes from Python (Programming Language).
Raspberry
+ =
Python
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Comes In Different Models
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Comes In Different Models
-Continued
Raspberry Pi Model B Raspberry Pi Model B+
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Latest Model
Raspberry Pi 2 Model B
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Features Summarized
Raspberry Pi is:
● A credit card sized computer
● Has Broadcom BCM2836 SoC [Raspberry Pi 2 Model B]
● Has 900MHz quad-core ARM Cortex-A7 CPU
● Features 1GB RAM and full HDMI support
● Low-power (~1W) and relatively low-cost (approx. $35)
● Can run full range of ARM GNU/Linux distributions
● Multiple USB ports; Ethernet port
● 3.5mm audio jack; MicroSD card slot
● Fanless; Instant start up
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Questions?
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