introduction to the internet of things

Sayed Chhattan Shah

Department of Information Communications Engineering

Hankuk University of Foreign Studies Korea

www.mgclab.com

The Internet of Things

http://www.mgclab.com/


https://sites.google.com/site/chhattanshah/


IoT is simply a concept wherein machines and

everyday objects are connected via the Internet



In 1991 Mark Weiser described ubiquitous

computing a world in which objects of all kinds

could sense, communicate, analyze, and act or

react to people and other machines

autonomously



Sensors

o A generic term intended to capture the concept of a

sensing system comprising sensors, microcontrollers,

modem chips, power sources, and other related

devices

Converts a non-electrical input

into an electrical signal that

can be sent to an electronic

circuit



Actuator

o a device that converts an electrical signal into action,

often by converting the signal to nonelectrical energy,

such as motion

A simple example of an actuator is an

electric motor that converts electrical

energy into mechanical energy



Active sensors

o Emit energy of their own and then sense the response of

the environment to that energy

Radio Detection and Ranging (RADAR)

Passive sensors

o Passive sensors simply receive energy that is produced

external to the sensing device

A standard camera is embedded with a passive

sensor—it receives signals in the form of light and

captures them on a storage device



Factors driving adoption within the IoT

oCheaper sensors

o Smarter sensors

o Smaller sensors



Challenges and Potential Solutions

o Power consumption

o Security of sensors

o Interoperability

Most of the sensor systems are designed for specific

applications

• Interoperability issues in heterogeneous sensor systems

related to communication, exchange, storage and

security of data, and scalability

• Communication protocols are required to facilitate

communication between heterogeneous sensor systems



Networks

ENABLING NETWORK TECHNOLOGIES




oData rates

o Internet transit prices

oPower efficiency

o IPv6 adoption



Internet transit prices in the US




o Interconnections

Different network technologies require gateways to connect

with each other. This adds cost and complexity, which can

often make security management more difficult

o Network penetration

Limited penetration of high-bandwidth technologies

o Security

o Power

Power-aware routing protocols

Sleep-scheduling protocols



ZigBee

o Technological standard created for control and sensor

networks

o Based on the IEEE 802.15.4 standard

o Wireless personal area networks

o Frequency band up to 2.4GHz



ZigBee

o Data rates of 20 kbps and up to 250 kbps

o Support for Low Latency Devices

o CSMA-CA Channel Access

o Low Power Usage consumption

o Supports large number of nodes

o Very long battery life



ZigBee Protocol Architecture



ZigBee Media Access Control Layer

o Carrier-sense multiple access with collision

avoidance



ZigBee Network Layer

o Starting a network

o Managing end devices joining or leaving a network

o Route discovery

o Neighbor discovery



ZigBee Application Support Sublayer

o Provides the services necessary for application objects

and the ZigBee device object to interface with the network

layer for data and management services

Some of the services provided by the APS to the

application objects for data transfer are request,

confirm, and response




o Application object

Defines input and output to the APS

• For example, a switch that controls a light is the

input from the application object, and the output is

the light bulb condition.

Each node can have 240 application objects




o ZigBee device object

Performs control and management of application objects.

ZDO performs overall device management tasks

• Determines the type of device in a network

» end device, router, or coordinator

• Performs device and service discovery

• Initializes coordinator for establishing a network

• Security management

• Network management

• Binding management



ZigBee Devices

ZigBee Coordinator (ZC)

oOne required for each ZB network.

o Initiates network formation.

ZigBee Router (ZR)

oParticipates in multihop routing of messages.

ZigBee End Device (ZED)

oDoes not allow association or routing.

oEnables very low cost solutions


ZigBee Network Topologies

ZigBee Coordinator

ZigBee Router

ZigBee End Device

Star

Mesh

Cluster Tree



Standards

o Data collected by sensors in different locations are

aggregated so that meaningful conclusions can be drawn

o Aggregation is achieved through the use of various

standards depending on the IoT application at hand



Standards

o Technology standards

Such as network and communication protocols

o Regulatory standards

Such as security and privacy of data



Augmented intelligence

o Extracting insight from data requires analysis

o Analysis is driven by cognitive technologies



Types of analytics



Cognitive technologies

o Computer vision

Ability of computers to identify objects, scenes, and

activities in images

o Natural-language processing

Ability of computers to work with text the way humans

do, extracting meaning from text or even generating

text that is readable

o Speech recognition




o Availability of big data

Artificial intelligence models can be improved with large

data sets that are more readily available

o Growth in crowdsourcing and open-source analytics

software

o Real-time data processing and analysis




o Inaccurate analysis due to flaws in the data or model

o Legacy systems’ ability to analyze unstructured data

Most IoT interactions generate unstructured data

o Legacy systems’ ability to manage real-time data



Augmented behavior

o The concept of augmented behavior is the doing of some

action that is the result of all the preceding stages of the

value loop—from sensing to analysis of data



IoT Functional View


IoT Implementation View


Context Aware Computing for The Internet of Things

Sensors generate enormous amounts of data – Big Data

o To add value to raw sensor data we need to understand it

Use context aware computing to understand sensor data

o Context-aware computing allows us to store context

information linked to sensor data so the interpretation

can be done easily and more meaningfully


Context Awareness Fundamentals

Context is any information that can be used to

characterize the situation of an entity

o An entity is a person, place, or object that is considered

relevant to the interaction between a user and an

application, including the user and applications themselves

Raw sensor data – GPS sensors readings

If we put the GPS sensor readings in such a way that it

represents a geographical location, we call it context

information



A system is context-aware if it uses context to provide

relevant information or services to the user, where

relevancy depends on the user’s task

Context-aware Application Features

o Presentation Context can be used to decide what

information and services need to be presented to the user

When a user enters a supermarket and takes their smart

phone out, what they want to see is their shopping list

• Context-aware mobile applications need to connect to kitchen

appliances to retrieve the shopping list and present it to the user



Context-aware Application Features

o Execution Automatic execution of services

When a user starts driving home from their office, the IoT

application employed in the house should switch on the air

condition system and switch on the coffee machine to be

ready to use by the time the user steps into their house.



Context Types

Primary context

Any information retrieved without

using existing context and without

performing any kind of sensor data

fusion operations

Secondary context

Any information that can be

computed using primary context


Context Life Cycle
