CSE IoT II year II semester

1. Definition:
IoT is a dynamic global network infrastructure of physical and virtual objects having unique
identities, which are embedded with software, sensors, actuators, electronic and network
connectivity to facilitate intelligent applications by collecting and exchanging data.
Characteristics of IoT:
Various characteristics of IoT are:
 Dynamic and self-adapting
 Self-configuring
 Interoperable Communication protocols
 Unique identity
 Integrated into information network
Dynamic and self-adapting:
The IoT devices can dynamically adapt with sensed environment, their operatingconditions, and
user’s context and take actions accordingly. For ex: Surveillance System.
Self-configuring:
IoT devices can be able to upgrade the software with minimal intervention of user, whenever they
are connected to the internet.
They can also setup the network i.e a new device can be easily added to the existing network. For
ex: Whenever there will be free wifi access one device can be connected easily. Interoperable
Communication:
IoT allows different devices (different in architecture) to communicate with each other as well as
with different network. For ex: MI Phone is able to control the smart AC and smart TV of
different manufacturer.
Unique identities:
I. The devices which are connected to the internet have unique identities i.e IP address through
which they can be identified throughout the network.
II. The IoT devices have intelligent interfaces which allow communicating with users. It adapts
to the environmental contexts.
III. It also allows the user to query the devices, monitor their status, and control them remotely,
in association with the control, configuration and management infrastructure.
Integrated into information network:
I. The IoT devices are connected to the network to share some information with other
connected devices. The devices can be discovered dynamically in the network by other devices.
For ex. If a device has wifi connectivity then that will be shown to other nearby devices having
wifi connectivity.
II. The devices ssid will be visible though out the network. Due to these things the network is
also called as information network.
III. The IoT devices become smarter due to the collective intelligence of the individual devices in
collaboration with the information network. For Ex: weather monitoring system. Here the
information collected from different monitoring nodes (sensors, arduino devices) can be
aggregated and analysed to predict the weather.

2. Physical Design of IoT:
The physical design of IoT (internet of things) includes
1.Things
2.Protocols
Things
Things in IoT refers to IoT devices. Things have unique identities. Things can perform sensing,
actuation, and monitoring.
The examples of IoT devices are:
 Home appliances: smart TV, smart refrigerator, smart AC, etc.
 Smart phones and computers
 Wearables: smart watch, smart sensors, etc.
 Automobiles like self-driving cars
 Energy systems
 Retail : smart payment
 Printers
 Industrial machines
 Healthcare: smart watch, smart healthcare, etc.
 Surveillance: smart cameras, smart trackers, etc.
Things can exchange data with other connected devices and applications, collect data from other
devices, and process the data either locally or send it to centralized servers or cloud. IoT devices
can have several interfaces like:
 I/O interfaces for sensors
 Interface for Internet connectivity
 Memory and storage connectivity interfaces
 Audio/video interfaces
An IoT thing or device is made up of different components. The generic block diagram of an IoT
thing or device is given below:
An IoT device provides connectivity interfaces like USB, RJ45, etc. It contains a microcontroller
or processor for computation tasks. It provides audio/video interfaces like HDMI, RCA, 3.5mm
audio channel. It contains memory interfaces like DDR. It might support graphics by providing a
separate Graphical Processing Unit (GPU), it provides storage interfaces like MMC, SDIO.

3. Finally, it might provides different I/O interfaces for connecting sensors and actuators like UART,
SPI, I2C and CAN.
Connectivity (RJ 45, USB): This component is used to connect the IoT device to the internet.
Processing unit (CPU): This is used to control all the other components as well as it processes the
instruction present in the algorithm.
Audio/ video unit: This is used to connect the monitor or speaker.
HDMI: High definition multimedia interface. It supports uncompressed all digital audio video
interfaces which provides all digital audio and video via a single cable. HDMI provides an
interface between any audio/video source such as set-top box, DVD player or audio/ video
receiver and audio and or video monitor such as a digital television over a single cable. HDMI
supports high definition video, plus multi-channel digital audio on a single cable.
/3.5 mm audio: This is used for audio.
RIC: Radio Corporation of America. It is sometimes called as phono connector. It is a type of
electrical connector commonly used to carry audio and video signals.
I/O interfaces: This is used to connect sensors, actuators, relay or any external devices.
UART: universal Asynchronous Receiver Transmitter. It is used to provide serial communication.
SPI: Serial peripheral interface. It is used to provide serial communication between different
devices or you can say between monitoring node and controlling node or coordinator node. In SPI
there will be a single master and multiple slaves.
There are 4signals. CHIPENABLE with a bar (active low ) , MISO, MOSI, clk/Slk/Sck.
Since multiple slaves are there so the slave will choose them using CHIPENABLE signal. If low
voltage will be given to the slave then that slave will be able to communicate with the master.
MISO: Master in Slave out. i.e Master will not send anything it will only receive and slave out i.e
slave will only send.
MOSI: Master out slave in i.e master will send the data and receiver will receive.
clk/slk/sck: It will synchronise the master and slave.
I2C: Inter integrated circuit. Here multiple masters can communicate with multiple slaves.
CAN: Controller area network. It is designed to allow micro controller and devices to
communicate with each other in applications without a host computer.
Storage: This is used to store or record the sensed data.
SD: Secure digital. This is used to hold the SD card which is a non-volatile memory card
format. SD card is a popular storage media for digital cameras and other mobile devices.
SDIO: It is used to connect external HDD.
MMC: Multi Media card. It is a flash memory based memory card standard. It is a popular
storage media for digital cameras and other mobile devices.
GPU: Graphics processing unit. It is useful for the resolution of the screen and used for high
end games.
Memory: There are used for temporary storage and for execution of instruction.

4. IoT Protocols:
A protocol is a set of rules that governs the communication between two or more devices. A
protocol defines the rules, syntax, semantics and synchronization of communication and possible
error recovery methods. An overview of different protocols used in IoT with respect to TCP/IP
protocol stack is given below:
Link Layer Protocols
The link layer is responsible for establishing and terminating links between the nodes. The
packets or data grams travel through these links. The link layer also defines the format of packet
that is to be communicated across the link and is responsible for physical addressing. The link
layer also handles error detection, retransmission, flow control and access of the link. Protocols
generally used at this layer are Ethernet, Wi-Fi, WiMax, LR-WPAN, cellular technologies, etc.
Network Layer Protocols:
The main role of the network layer is transfer the packet from sender to receiving host. The
network layer also handles routing, which involves selecting the next node and forwarding the
packets across the communication path. The network layer is also responsible for logical
addressing (like IP address) and for congestion control which prevents the network from being
overloaded with traffic.

5. Different protocols at network layer are:
 IPv4 (32-bit addresses)
 IPv6 (128-bit addresses)
 6LoWPAN (IPv6 over Low power Wireless Personal Area Network)
IPv4 IPv6
Internet protocol version 4 Internet protocol version 6
It is 32 bit dotted decimal It is 128 bit colon hexa decimal
It supports 232
number of addresses It supports 2128
number of addresses
It supports point to multipoint connection. It supports point to point connection
All the applications have same priority. Different applications have different priority.
It is connection less. It is connection oriented.
Here at each router fragmentation and
defragmentation takes place.
Here at each router fragmentation and
defragmentation takes place.
IPv6 over low power personal area network. It brings IP protocol to the low power devices which
have limited processing capability. It operates in 2.4 GHz frequency. It supports data transfer rate
up to 250kb/s. 6LoWPAN works with the 102.15.4 link layer protocol.
Transport Layer Protocols
The main role of transport layer is providing end-to-end communication between the applications
running on hosts. The transport layer provides a logical communication channel through which
the end applications can communicate with each other. The transport layer is implemented on the
end hosts. It is not present in the routers. The transport layer is also responsible for the reliable
delivery of the message across the end nodes, flow control and multiplexing and demultiplexing
of the channels at end nodes.
Different protocols at transport layer are:
 TCP (Transmission Control Protocol)
 UDP (User Datagram Protocol)
Services supported by
TCP/UDP
TCP UDP
1. Abbreviation Transmission Control
Protocol
User Datagram protocol
2. Protocol data unit segment datagram
3. Connection Connection oriented Connection less
4. Reliability Reliable and in order as
connection oriented
Unreliable and out of order
as connection less.
5. Phases 3 phase i.e connection
establishment, data transfer,
connection release.
One phase i.e data transfer
6. Delay between data
unit
Uniform delay as throughout
the travel they follow same
path.
Non uniform delay as
throughout the travel they
follow different path.
7. Congestion Occurs during connection
establishment
Occurs during data transfer.
8. Resources Dedicated Shared

6. 9. Utilisation of
resources
Less utilisation due to
connected path and dedicated
resources.
Proper utilisation due to
shared resources
10. Fault tolerant
technique
No fault tolerant technique Uses fault tolerant technique
11. Message size Prefer long message Prefer short message
12. Flow control Provides flow control with
help of ACK
(acknowledgement) field and
sequence number field.
Does not provide flow
control
13. Error control It provides error control It does not provide error
control
14. Dependency on
ICMP (Internet
control Message
Protocol )
Does not depend upon ICMP depends upon ICMP at
network layer.
15. Multi casting Does not support Supports multicasting
16. Broad casting Does not support Supports broadcasting
17. Examples of
applications using
TCP/ UDP
HTTP: 80
HTTPS: 443
SMTP: 25
Telnet: 23
TFTP: 69
NTP: 123
DHCP: 67,68
SNMP: 161
Application Layer Protocols
The application layer is where the users of an IoT application interact with the IoT
application/system. The application layer allows the users to interact with the IoT sensors and
access other services provided by the communication network. The application layer provides
services like authentication, naming, message formatting, email, etc, to the users.
Application layer protocol:
 HTTP (Hyper Text Transfer Protocol)
 CoAP (Constrained application protocol)
 Websocket
 MQTT (Message queue telemetry transport)
 XMPP (Extensible messaging and presence protocol)
 DDS (Data distribution service)
 AMQP (Advanced message queuing protocol)
HTTP:
It is a web transfer protocol.
It uses port no. TCP:80 in transport layer
It uses URI to identify HTTP resources
It uses Request-Response model.
It uses Cleint-Server architecture.
It uses PUT, GET, POST, DELETE HEAD, TRACE, OPTIONS method tocommunicate with
the resources.
CoAP
I. It is a web transfer protocol.
II. It is suitable for machine to machine communication.

7. III. It is applicable for constrained environment with constrained device andnetwork. It is a
stateful protocol.
IV. It uses UDP 5683 port number in transport layer.
V. It uses request- response model.
VI. It uses client server architecture.
VII. It uses PUT, GET, POST, DELETE, HEAD, TRACE, OPTIONS.
VIII. It is designed to work with HTTP
Websocket:
I. It allows full duplex communication over a single socket connection toprovide data transfer
between client and server keeping TCP connection open.
II. It is a stateful protocol.
III. It uses TCP as transport layer protocol.
IV. It uses request-response communication model.
V. It uses client server architecture
MQTT:
It is a low weight messaging protocol (small message size).
Suitable for constrained environment where devices has low processing,capabilities, less
memory and less band width.
It uses TCP as transport layer protocol and uses port number TCP 1883.
It uses Publish-subscribe model.
It uses client- server architecture.
XMPP:
It is a decentralised protocol.
It is suitable for real time communication and streaming small chunk of XMLdata between
network entities in real time.
It uses TCP as transport layer protocol.
Client server architecture allows client to server and server to servercommunication.
It provides range of application such as messaging, multiparty chat, voice/video call, gaming.
DDS:
It is a data centric middleware standard.
It provides device to device or machine to machine communication.
Uses publish subscribe model.
It provides QoS (Quality of Service) control and configurable reliability.
AMQP:
It is an open application layer protocol for business messaging.
Supports point to point and publish/ subscribe model, routing, queuing.
It uses 5672 TCP.
Logical Design of IoT:
The logical design of internet of things includes: IoT Functional Blocks, IoT Communication Models, and
IoT Communication APIs.
IoT Functional Blocks
Different functional blocks in an IoT system or application are device, communication, services,
application, management, and security.

8. The device block contains sensing, actuation, monitoring and control functions for controlling the
devices. The device block interacts with the communication block.
The communication block contains different protocols (wired or wireless) through which the data
moves from devices to Internet and from Internet to devices. The services block acts as a
middleware which can provide services like device identification, device discovery, or data
processing and analysis.
The users of an IoT application interacts with the application block. It provides user interface with
which the user can access the data sent by the sensors, perform operations on that like
aggregation, simplification, etc. and visualize that data.
The application interface can also provide control functions for controlling the sensors, actuators
or functionality of the application. The management block allows us to manage the other blocks
like device, services, communication, application, and security. The security block provides
different security services like confidentiality, integrity, availability, and authentication.
IoT Communication Models
Internet of things supports different communication models between the entities in an IoT system.
These communication models are:
 Request-Response Model
 Publish-Subscribe Model
 Push-Pull Model
 Exclusive Pair Model
Request-Response Model

9. The two main entities in request-response model are client and server. The client can be a web
application, mobile application, etc. The client may be a browser requesting web pages or
accessing an email. Each access of a resource will be treated as request.
The server accepts the requests from the clients, processes them and sends back responses to the
clients. While processing the requests, the server might access additional resources like file,
databases, etc. The request-response model is stateless, i.e., the requests in a session are not
related to each other with respect to a server. Each request is treated as a new one and is
completely unrelated to the previous requests.
Publish-Subscribe Model:
The three main entities in publish-subscribe model are publisher, consumer, and broker. The
publisher always publishes messages at a pre-defined interval. The sensors in IoT can be thought
of as publishers. The publishers publish data as topics. The broker is an entity that maintains
different topics to which consumers subscribe. The broker is generally a server.
The published messages of publishers are maintained by the broker. The consumers consume the
data published by the publishers. A consumer is generally the IoT application through which the
users interact. A consumer can subscribe to one or more topics maintained by a broker.
Push-Pull Model
The main entities in a push-pull model are publisher, consumer, and queues. The publisher
pushes messages to the queues. The sensors in IoT can be thought of as publishers of data. One or
more queues store that data pushed by the publishers.
Unlike the publish-subscribe model, there is ordering of messages in push-pull model. The
consumers pull the messages from the queues and consume the messages. A consumer is

10. generally the IoT application through which the users interact.
Exclusive Pair Model
The main entities in an exclusive pair model are client and server. The client and server establish a
full duplex connection for sending and receiving data. Before sending a request, the client
establishes a connection with the server and then sends the request.
The data requests can be one or more. The server receives these requests through the same
connection and sends back responses. After the data transfer is complete, the connection between
the client and server is terminated. Unlike publish-subscribe model, exclusive pair model is
stateful. So, the server can automatically identify that the request is coming from a previous client
or not.
IoT Communication APIs:
An Application Programming Interface (API) provides an unified interface to access the server
resources. An API is the one which connects the things together in the Internet of Things. APIs
act as a point of interaction between the IoT devices and the Internet and/or other elements within
the network.
In IoT there two types of communication APIs. They are:
 REST-based communication APIs
 WebSocket-based communication APIs
REST-based Communication APIs
REpresentational State Transfer (REST) is a set of architectural principles by which we can
design web services and web APIs that focus on a system’s resources and how resource states are
addressed and transferred. REST APIs follow request-response model. REST architectural
constraints apply to components, connectors, and data elements within a system.
Consider the example of accuweather.com as shown below. Users can see the weather at a given
location though accuweather’s weather application in their mobiles. This application uses a REST
API provided by accuweather to access the weather details. When a user selects a location in the
mobile app, the application sends a HTTP or HTTPS request as shown in the figure below.
Accuweather’s server responds back with the weather details.

11. In a REST-based communication, the client sends HTTP or HTTPS requests like GET, POST,
PUT, DELETE, etc., to the server where the REST-based API will accept these requests, process
them and send back responses. The responses sent back to the clients will be in Extensible
Markup Language (XML) or JavaScript Object Notation (JSON) format as shown below.
A RESTful web service is a web API implemented using HyperText Transfer Protocol (HTTP)
and REST principles. RESTful web service is a collection of resources which are represented by
URIs. Clients send requests to these URIs using HTTP or HTTPS methods like GET, POST,
PUT, DELETE.
REST architectural constraints are:
Client-Server: As REST is based on request-response model, the communication involves two
entities namely, client and server. A client sends requests and the server process the requests and
sends back responses.
 Stateless: As REST follows request-response model, it is stateless. The server will not be able
to associate a set of requests to a client. It will treat each request as a new request.
 Cacheable: The response sent by the server might be cached at the client side. This will allow
the client to load the response faster next time when it is needed.
 Layered System: The REST architecture is layered where there is a clear separation in the
functionality carried by different entities.
 Uniform Interface: REST provides an uniform interface for all kinds of applications and
devices.
 Code on Demand: REST enables to access the code based on a specific request. Based on the
request, the code that is going to be executed might be changed.
The REST-based communication can be summarized and illustrated as shown below.

12. WebSocket-based Communication APIs
WebSocket-based API creates full-duplex communication between clients and servers. It follows
exclusive Web pair communication model. WebSocket-based communication is stateful.
No need to establish connection for each request. It is suitable for IoT applications that need low
latency. WebSocket-based communication process can be illustrated as shown below.
Difference between REST and Websocket:
REST Websocket
1. It supports Request-response
communication model.
2. It supports stateless protocol.
3. It supports unidirectional
communication between client
and server as only client can send
request to server and server only
respond to the request.
4. It is half duplex.
5. It uses multiple TCP connection
for each search over HTTP.
6. Since it does not store the request
information so each time it needs
to provide all the information
while creating communication
with server. For this reason header
overhead increases.
7. It supports both horizontal and
vertical scalability.
1. It supports Exclusive-pair
communication model.
2. It supports stateful protocol.
3. It supports bidirectional
communication between client
and server i.e client and server
both can request to each other.
4. It is full duplex.
5. It uses single TCP connection for
search over HTTP.
6. Header overhead is less.
7. Vertical scaling is easier than
horizontal scaling.

13. IoT Levels and Deployment Templates :
An IoT system comprises the following components: Device, Resource, Controller Service,
Database, Web service, Analysis Component and Application.
Device : An IoT device allows identification, remote sensing, remote monitoring capabilities.
Resource: Software components on the IoT device for
-accessing, processing and storing sensor information,
-controlling actuators connected to the device.
- enabling network access for the device.
Controller Service: Controller service is a native service that runs on the device and interacts
with the web services.
- It sends data from the device to the web service and receives commands from the application
(via web services) for controlling the device.
Database: Database can be either local or in the cloud and stores the data generated by the IoT
device.
Web Service: Web services serve as a link between the IoT device, application, database and
analysis components.
It can be implemented using HTTP and REST principles (REST service) or using the WebSocket
protocol (WebSocket service).
Analysis Component: Analysis Component is responsible for analyzing the IoT data and
generating results in a form that is easy for the user to understand.
Application: IoT applications provide an interface that the users can use to control and monitor
various aspects of the IoT system.
-Applications also allow users to view the system status and the processed data.
Following are the six different levels of IoT:
Level 1: In this level all the components are deployed locally. There is no any cloud or external
network involved in the process.
Sensors, routers, cloud components, application etc. all are at the user’s end. This standard is good
for those ecosystems where data is neither big nor varying. A uniform stream of data is coming
from a pre-set group of sensors and that is all happening in a simple way.
An example of Level 1 IoT is a smart home.
An app is used to monitor in-home automation, a few home appliances, and lights.
In a system with a single node IoT computer, lights, and/or other home appliances, a relay is
attached.
A REST service is used to view and update the status of lights and appliances by altering
values in a local database.
The controller service constantly tracks the database, keeps track of equipment, and activates
relay switches.
The locally deployed framework offers a graphical user interface (GUI) from which the user
can control lights and other household appliances.

14. Level 2: In this level all the components are deployed locally except the servers. There is a cloud
or an external network involved in the process.
At the user’s end there are only sensors, routers and application. The cloud part is having the
servers configured for the purpose of storage and analysis. This standard is good for those
ecosystems where data is big. A huge amount of data is coming from many components in the
ecosystem and that too on a rapid speed.
An example of Level 2 IoT is a smart irrigation.
 A single node monitors soil moisture and controls the irrigation system.
 If the moisture level falls below the prescribed predefined threshold, the irrigation system is
enabled.
 An IoT system detects soil moisture, and the controller service tracks it and sends the data to
the cloud.
 Moisture levels are shown to users in an application, which can be used to create an irrigation
schedule.
 This level has a voluminous size of data. Hence cloud storage is used.
 Data analysis is carried out locally. Cloud is used for only storage purposes.

15. Level 3: In this level all the components are deployed locally except the servers and the network
connectivity part. There is a cloud or an external network involved in the process.
At the user’s end there are only sensors and application. The cloud part is having the essential
networks for connectivity and servers configured for the purpose of storage and analysis. This
standard is good for those ecosystems where data is big and varying. A huge amount of data is
coming from many components deployed in many ecosystems and that too on a rapid speed.
An example of Level 3 IoT is a package monitoring in a distribution system.
 The movements that occur to the package are reviewed here. If they exceed the threshold, an
alarm is triggered.
 To detect these movements, the IoT system has gyroscope and accelerometer sensors.
 The controller service uses Websocket API to send real-time data to the cloud, which is
useful in real-time applications due to its low overhead.
 A cloud-based WebSocket-based service retrieves real-time data from IoT devices and stores
it in a database.
 It retrieves it as required for analysis.
 The data is voluminous, i.e. large data, in this case. The data sensing frequency is high, and
the collected sensed data is stored on the cloud because it is large.
 Data is analyzed in the cloud, and control actions are activated using a mobile app or a web
app based on the results of the analysis.

16. Level 4: In this level also, all the components are deployed locally except the servers and the
network connectivity part. In some cases, sensors are also in the cloud.
At the user’s end there is only the application. The cloud part is having the essential networks for
connectivity and servers configured for the purpose of storage and analysis. This standard is good
for those ecosystems where data is big, varying and is coming from mobile sources.
An example of Level 4 IoT is a Noise Monitoring System .
 In this system, several nodes are dispatched in various locations to detect noise in a specific
region.
 Sound sensors are examples of Nodes/Devices in this context.
 Each Node/Device is self-contained, with its own controller service that delivers data to the
cloud for storage and processing.
 This level includes numerous sensors, data collection, and analysis, as well as a control and
monitoring app.

17. Level 5: IoT is very similar to Level 4 but with one major advancement. In level 5 IoT,
coordinator devices are also there in the local part of the ecosystem. A coordinator device
coordinates a certain set of sensing devices. There is an Observer Node also in the cloud part that
observes the entire process.

18.  Nodes/devices are mainly used to detect temperature, moisture, and CO2 levels in this kind of
system.
 So, what sensors could have been used properly must be clear to you? Fine! Fine! Here the
sensors are used for temperature, humidity, and CO2.
 These nodes detected the data, the coordinator node collects the data and the controller service
on the coordinator is migrated into the cloud.
 Node Coordinator serves as a portal to the IoT-based system and provides Internet access.
 Analytics module can be used to predict/generate results to the data stored in the cloud.
 The data collection and data analysis are performed at the cloud level.
Level 6: IoT is very similar to Level 5 but with one major advancement. In level 6 IoT,
coordinator devices are replaced by a single component Centralized Controller and that is there in
the cloud part of the ecosystem.
The example of a system of weather surveillance.
 Numerous temperature, humidity, stress, etc. sensors are contained in this system.
 These nodes are installed in various locations and are sent via the WebSocket-based API to
cloud-based storage in real-time.
 Any node update or changes are performed via the centralized controller.
 The analytics module is used to forecast/generate reports to the data stored on the cloud.

19. IoT Issues and Challenges Security
• Cyber Attacks, Data Theft Privacy
• Controlling access and ownership of data. InterOperability
• Integration Inflexibility Legality and Rights
• Data Protection laws be followed, Data Retention and destruction policies Economy and Development
• Investment Incentives, Technical Skill Requirement
IoT enabling technologies:
The technologies which are cooperative with IoT those are as follows.
 Wireless sensor networks
 Cloud computing
 Big Data analytics
 Embedded systems
 Communication protocols
Wireless Sensor networks:
1. Wireless sensor network comprises of distributed devices, wireless sensors. These devices with
sensors are used to monitor the environment and physical conditions. Since all the nodes are
wireless so they communicate with each other through wifi or Bluetooth.
2. A WSN consists of several end nodes and routers as well as coordinator.
3. Sensors are attached with end nodes. Each router can also be called as end node.
4. Routers are responsible for routing the data packets from end nodes to the coordinator
nodes. Coordinator node connects the WSN to the internet. The Coordinator node can be another
arduino, raspberry pi or any other IoT DIY device.
5. It collects the data from all the nodes.
6. WSNs are enabled by wireless communication protocols such as IEEE802.15.4.
7. It can also be enabled by ESP 8266 and ZigBee.
8. ZigBEE Bluetooth module is based on IEEE802.15.4. It operates at 2.4 GHz frequency. It
offers data rate up to 250 KB/s and ranges from 10 to 100 meters depending upon power output
and environmental conditions. In WSN the devices can reconfigure themselves i.e new nodes can
be added to the networks and software can be updated automatically whenever they will be
connected to the internet.
9. Ex. of Wireless sensor network: Weather monitoring system, Indoor air quality
monitoring, soil moisture monitoring, surveillance system, smart grids, machine prognosis and
diagnosis.
Cloud Computing:
1. It is an emerging technology which enables on-demand network access to computing
resources like network servers, storage, applications and services that can be rapidly provisioned
and released.
2. On demand: we invoke cloud services only when we need them, they are not permanent
part of IT infrastructure.
3. Pay as you go model: You pay for the cloud services when you use them, either for the
short period of time or longer duration (for cloud based storage).
4. Cloud provides various services such as
i. IAAS: Infrastructure as a service
ii. PAAS: Platform as a service
iii. SAAS: Software as a service

20. IAAS:
Instead of creating a server room we will hire it from a cloud service provider. Here user will not
use its local computer, storage and processing resources rather it will use virtual machine and
virtual storage, servers, networking of third party. Here the client can deploy the OS (operating
system), application of his own choice. User can start, stop, configure and manage the virtual
machine instances and virtual storage.
PAAS:
User can develop and deploy applications. For ex. We are using various online editors to write
codes like online arduino IDE, C IDE, APIs, software libraries. Here we don’t need to install
anything. The cloud service provider will manage servers, network, OS and storage. The users
will develop, deploy, configure and manage applications on the cloud infrastructure.
SAAS:
It provides complete software application or the user interface to the application itself. The user is
not concerned about the underlying architecture of cloud only service provider is responsible for
this. It is platform independent and can be accessed from various client devices such as
workstation, laptop, tablet and smart phone, running different OS. Ex: The online software we use
like online image converter, doc converter etc.
Big data analytics:
Big data refers to large amount of data which cannot be stored, processed and analysed using
traditional database like (oracle, mysql) and traditional processing tools. In big data analytics BIG
refers to 5 Vs.
• Volume
• Velocity
• Variety
• Veracity
• Value
Volume: volume refers to the massive amount of data generated from the IoT systems. There is
no threshold value for generated data. It is difficult to store, process and analyse using traditional
database and processing tools. Ex: The volume of data generated by modern IT, industrial and
healthcare system.
Velocity: The rate at which the data is generated from the IoT system. This is the primary reason
for the exponential growth of data. Velocity refers to how fast the data is generated and how
frequently it varies. Ex: Modern IT, industrial and other systems like social networking sites are
generating data at increasingly higher speed.
Variety: Variety refers to different forms of data. Since there are various domain of IoT so
various type of data are generated from different IoT domain. Those data is called as sparse data.
Those data include text, audio, video etc.. The variety of data is mainly divided into 3 types i.e.
structured
semi structured
unstructured
Structured data: The data which has a fixed format to be stored is known as structured data.
The data stored in database like oracle, mysql is an example of structured data. With a simple
query data can be retrieved from the database.

21. Semi-structured data: The data which has not a fixed format to be stored but uses some elements
and components through which they can be analysed easily is known as semi- structured data. Ex:
HTML, XML, JSON data
Unstructured data: The data which has not any fixed format. It is difficult to store and analyse. It
can be analysed after converting into structured data. Ex: Audio, video (gif, audio with lyrics),
Text (containing special symbols).
Veracity: The data in doubt is known as veracity. Sometimes what happen it is very difficult
accept the data stored in database. This happens due to typical error, corrupted storage or data.
Value: It is efficient to access big data if we can turn it into values i.e we can find greater insights
from it so that we can perform some action to get the desired output. This will be beneficial for
the organisation. Otherwise it has no use.
Embedded Systems:
1. An embedded system is a computer system that has hardware and software embedded to
perform specific task.
2. The key components of an embedded system include microprocessor or micro controller,
memory (RAM, ROM, Cache), networking units (Ethernet, Wi-Fi adapter), input/output units
(display, keyboard, etc) and storage (flash memory). They use some special types of processor
such as digital signal processor, graphics processor and application specific processor). Embedded
system uses embedded OS like RTOS.
3. Ex. Of embedded systems: digital watch, digital camera, vending machines.
Communication protocols:
1. Protocol is nothing but rules and regulations. Communication protocol is the backbone of
the IoT system.
2. It allows interoperability among various devices. It enables network connectivity and
coupling to applications.
3. It allows devices to exchange data over the network. These protocols define data exchange
format, data encoding, addressing schemes for devices and routing of packets from source to
destination. It also includes sequence control, flow control and retransmission of lost packets.