IoT Communication Protocols.docx for communication protocol

IOT

1. IoT Communication Protocols?
IoT devices are connected by wireless networks and sets of rules known as IoT
communication protocols, or simply IoT protocols. IoT devices can communicate
with one another using IoT protocols.
Factors to choose IoT Protocols
The perfect IoT communication protocol is decided by the special requirements
and limitations of a specific device. The following factors determine the
selection of IoT protocols
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Geographic Locations are the physical distances between two or more
devices that make an ecosystem.
Power consumption requirements is the duration for which the IoT
devices continue to operate on.
Physical Barriers are the barriers that exist between the devices inside
the IoT ecosystem, like walls, mountains, buildings, and so on.
List of Protocols for IoT devices
Communication protocols for IoT devices are like the languages used to
communicate with one another. Here are some of the top protocols
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1. MQTT (Message Queuing Telemetry Transport)
MQTT is a message protocol or collection of rules for machine-to-machine
communication that follows to predefined standards. Smart sensors, wearables,
and other Internet of Things (IoT) devices often require transmit and receive
data over a limited in resources network with limited bandwidth. These IoT
devices use MQTT for data transfer because it is simple to set up and effectively
communicates IoT data. MQTT enables messaging between devices and the
cloud.
Importance of MQTT
Due to its ability to provide the following advantages, the MQTT protocol has
become the industry standard for IoT data transmission
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Portable and Effective  MQTT can even be implemented on small
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microcontrollers because it uses very few resources when deployed on an
Internet of Things device. For example, two data bytes can be the

2. minimum size of a MQTT control message. Also, MQTT message headers
are reduced to maximise network bandwidth.
Adaptable  A small amount of code is needed to implement MQTT, and
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it uses very little power when it operates. A lot of IoT device connection is
supported by the protocol's built-in features. So you can link to millions of
these devices by implementing the MQTT protocol.
Trustworthy  Many Internet of Things devices are connected to
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unreliable cellular networks that have poor throughput and too much
latency. The IoT device reconnects to the cloud faster because of the the
built-in features in MQTT. In order to provide dependability for Internet of
Things use cases, it additionally specifies three different quality-of-service
levels: at most once (0), at least once (1), and exactly once (2).
Secure  Developers can easily encrypt communications and
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authenticate users and devices with MQTT by using modern
authentication protocols like TLS1.3, OAuth, Customer Managed
Certificates, and more.
MQTT Components
MQTT supports the publish/subscribe model by configuring clients and brokers
in the way mentioned below
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Client  Any device that runs a MQTT library, from a server to a
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microcontroller, is a MQTT client. The client performs the roles of
publisher and receiver when sending and receiving messages,
accordingly. In simple terms, a MQTT client device is any device that uses
MQTT for network-based communication.
Broker  The backend system that synchronises messages between the
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various clients is the MQTT broker. The broker's responsibilities
encompass receiving and screening communications, identifying which
clients have subscribed to each one, and forwarding the messages to
them. It is also in charge of additional duties like
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oVerifying and approving MQTT clients.
oTransferring messages to additional systems for analysis.
oTaking care of client sessions and missed messages.

3. oMQTT connection.
Connection  An MQTT connection is used to initiate communication
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between clients and brokers. Clients send a CONNECT message to the
MQTT broker to start the connection. By sending back a CONNACK
message, the broker certifies that a connection has been made. In order
for the MQTT client and the broker to communicate, a TCP/IP stack is
needed. Clients exclusively communicate with the broker and connect
with each other.
2. HTTP (Hypertext Transfer Protocol)
An application-level protocol designed for interconnected, collaborative,
hypermedia information systems is called HTTP. Since 1990, this has served as
the basis for data communication on the World Wide Web, or internet. HTTP is a
generic, stateless protocol that can be extended for additional uses by
manipulating its headers, error codes, and request methods.
In simple terms, HTTP is a TCP/IP based communication protocol that is used to
send data across the World Wide Web, including picture files, HTML files, and
query results. Since TCP 80 is the default port, you can use other ports as well. It
offers a common means of computer-to-computer communication. The HTTP
specification outlines the format and transmission method for client request
data to the server.
Features of HTTP
Three basic features make HTTP a simple but effective protocol
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Connectionless protocol  A browser operating as the HTTP client
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makes an HTTP request and then waits for a response. After the server
responds to the request and processes it, the client cuts off the
connection. Thus, only during the current request and response do the
client and server know about one another. When a client and server are
connected for the first time, more requests are made.
Media Independent  As HTTP is media independent, any kind of data
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can be sent over it as long as the client and server are both capable of
handling the data's content. Both the client and the server must use the
correct MIME-type to specify the content type.

4. Stateless  As already mentioned, HTTP's statelessness directly
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contributes to its connectionless nature. Only during a current request
are the server and client aware of one another. They both forget about
each other after that. The protocol's nature prevents both the client and
the browser from storing data between requests made on different web
pages.
3. CoAP (Constrained Application Protocol)
The web-based, application-layer CoAP protocol was created for limited devices,
like sensors. Sensors' processing power and memory are constrained. The
HyperText Transport Protocol (HTTP) protocol and the CoAP are comparable.
The Representative State Transfer (REST) architecture takes advantage of CoAP.
How CoAP Work?
CoAP allows devices like sensors and actuators to communicate across the
Internet of Things by acting as a sort of HTTP for limited devices. As an element
of a system, these sensors and actuators are managed and make a contribution
by transferring data. The protocol's low power consumption and little network
overhead are designed to ensure resilience in situations with limited bandwidth
and high congestion. CoAP can function on a network where TCP-based
protocols, like MQTT, are unable to share data and interact efficiently because
of high congestion or poor connectivity.
Furthermore, devices working in low signal quality may communicate data
consistently thanks to the efficient and traditional CoAP capabilities, and an
orbiting satellite can successfully sustain its distant communication. Moreover,
billion-node networks are supported by CoAPs. The DTLS parameters that are
used by default are similar to 128 bit RSA keys in terms of security.
UDP is the fundamental network protocol used by COAP. In simple terms, COAP
is a client-server Internet of Things protocol, like HTTP, in which a request is
made by the client and a response is sent by the server. HTTP and COAP both
use the same techniques.
4. AMQP (Advanced Message Queuing Protocol)
Advanced Message Queuing Protocol is referred to as AMQP. This widely used
standard, which essentially operates at the application layer, is primarily used to

5. create unmatched communication functionality between broker and client
parties.
While clients collect and handle the messages, the publisher is responsible for
their creation. In this entire process, the function of brokers like RabbitMQ is to
ensure that messages are sent straight from the publisher to the client.
Among its most crucial elements are queuing, routing, and message
orientation. Compatibility with different infrastructure configurations is
achieved when AMQP is used. It lets developers use any provided client library
and broker that meets with the protocol.
Components of AMQP
Developers need to be familiar with specific components needed for AMQP
model deployment
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Exchanges  Messages are retrieved by Exchange and carefully arranged
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in the appropriate queue. There are four categories in it: Direct, Topic,
Headers, and Fanout. To give you more specifics, it is an essential part of
the broker.
Channel  A multiplexed virtual connection among AMQP peers that is
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constructed inside of an already-existing connection is referred to as a
channel.
Message Queue  It is a recognised entity that helps in connecting
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communications to their source or resources.
Binding  Bindings are a set of pre-established rules related to
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exchanges and queues. It handles the delivery and transmission of
messages.
Virtual Hosts  One platform that provides the broker with segregation
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capabilities is called vhost. There can be more than one operational vhost
at once, depending on the users and their access privileges.
5. Bluetooth and Bluetooth Low Energy (BLE)
Bluetooth
Bluetooth is a LAN technology that operates within a limited range and is used
to link small devices and gadgets together, enabling personal data transfer
between them. Often referred to as Bluetooth classic, it allows linked devices to

6. communicate across the 2.4 GHz ISM unlicensed frequency. Basic Rate (BR) and
Enhanced Data Rate (EDR) are the two different data rate types available for the
Bluetooth Classic version.
Bluetooth Low Energy (BLE)
Bluetooth Classic and Bluetooth Low Energy (BLE) are comparable. IEEE 802.15
has standardised this short-range wireless LAN communication technique. Also,
it uses unlicensed 2.4 GHz ISM spectrum. The main feature that sets BLE apart
is its low power consumption, which is maintained while keeping the same
communication range as Bluetooth classic. BLE was initially made commercially
available in 2011. It is commonly used in power-saving products for home
automation, security, healthcare, and fitness.
6. Zigbee
Zigbee is a low-power wireless mesh network standard designed for wireless
control and monitoring applications that use battery-powered devices. Zigbee
allows communication with reduced latency. Microcontrollers and radios are
commonly integrated with Zigbee chips.
Zigbee expands upon IEEE standard 802.15.4 for low-rate wireless personal area
networks (WPANs), which defines the physical layer and media access control.
The network layer, application layer, Zigbee Device Objects (ZDOs), and
manufacturer-defined application objects are the four other essential parts of
the specification. Device discovery, device security, device role tracking, and
network join request management are among the responsibilities of ZDOs.
Generic mesh networking as well as star and tree networks are naturally
supported by the Zigbee network layer. There has to be one coordinator device
per network. The coordinator in a star network needs to be the centre node.
Zigbee routers can be used to expand network-wide communication through
trees and meshes.
Use Cases
Zigbee protocols are like a special language used by devices that need to
conserve power and don't need to send a lot of data quickly. This means the
devices can last a long time without needing new batterieslike at least two
years.
People use Zigbee in lots of different situations, like
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7. Making homes smart and automated.
Setting up wireless networks of sensors.
Controlling machines and systems in factories.
Putting sensors in things like thermostats or wearable health devices.
Collecting medical information from patients.
Keeping buildings safe with alarms for fire or break-ins.
Making it possible to change settings on microphones without having to
be close to them.
But Zigbee is not good for situations where devices move around a lot. So it is
not the best choice for things like military operations where fast data transfer
and lots of movement are important.
7. LoRaWAN (Long Range Wide Area Network)
LoRa is a radio modulation technique that uses chirp spread spectrum
technology to manipulate radio waves in order to convey information in a multi-
symbol manner. The name "LoRa" can also refer to the communication network
that IoT apps use, or the systems that enable this modulation technology.
LoRa's cost and long-range capabilities are its key benefits. Smart cities are a
common use for LoRa, where cheap, low-powered IoT devices (usually sensors
or monitors) placed across a broad area regularly transmit small data packets to
a central administrator.
Based on the LoRa radio modulation method, LoRaWAN is a low-power wide
area networking protocol. It controls communication between end-node devices
and network gateways as well as wirelessly connects devices to the internet.
Because LoRaWAN is an inexpensive, bi-directional, long-range communication
protocol with low power consumption-devices can operate for ten years on a
small battery, its use in business environments and smart cities is growing. For
network deployments, it makes advantage of the unlicensed ISM (Industrial,
Scientific, and Medical) radio frequencies.
There are two ways an end device using LoRaWAN can connect to a network
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8. Over-the-air Activation (OTAA)  In order to connect to the network, a
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device needs to establish both an application session key and a network
key.
Activation by Personalization (ABP)  With Activation by
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Personalisation (ABP), a device's network communication keys are
hardcoded resulting in a less secure but faster connection.
8. DDS (Data Distribution Service)
DDS uses a publish-subscribe model similar to MQTT; the primary distinction is
the absence of brokers. It means that every publisher such as temperature
sensors and every subscriber such as cell phones are linked to the same
network. To prevent bottlenecks, this network known as Global Data Space
(GDS) interconnects every node with every other node.
Standards and products for communications middleware are many. Because of
its distinct data focus, DDS is an ideal fit for the Industrial Internet of Things.
The majority of middleware functions by transferring data between systems
and applications. Data centricity makes sure that all communications have the
background knowledge that an application needs in order to understand the
data that it receives.
The fundamental characteristic of data centricity is that DDS has knowledge of
the data it contains and manages its distribution. When using conventional
message-centric middleware, programmers have to develop message-sending
code. When writing code, programmers use data-centric middleware to define
when and how to communicate data, as well as to share data values directly.
DDS directly enables controlled, managed, secure data sharing for you,
removing the need for you to handle all this complexity in the application (your)
code.