UNIT 4

PROTOCOL STANDARDIZATION FOR IOT

IoT protocols and standards are often overlooked when people think about the
Internet of Things (IoT). More often than not, the industry has its attention
firmly fixed upon communication. And while the interaction among
devices, IoT sensors, gateways, servers, and user applications is essential to IoT,
communication would fall down without the right IoT protocols.

What Are IoT Protocols?

Before we dive into common IoT protocols, let's define the term "protocol" at a
high level.

Protocols are a set of rules for transmitting data between electronic devices
according to a preset agreement regarding information structure and how
each side will send and receive data. Correspondingly, IoT protocols are
standards that enable the exchange and transmission of data between the
Internet and devices at the edge.

IoT protocols can be divided into two categories: IoT network protocols and IoT
data protocols. Data protocols mainly focus on information exchange, while
network protocols provide methods of connecting IoT edge devices with other
edge devices or the Internet. Each category contains a number of protocols that
each have their own unique features. We'll take a look at those next.

Why are IoT protocols important?

IoT protocols are an integral part of the IoT technology stack. Without IoT
protocols and standards, hardware would be useless. This is because IoT
protocols are the things that enable that communication—that is, the exchange
of data or sending commands—among all those various devices. And, out of
these transferred pieces of data and commands, end users can extract useful
information as well as interact with and control devices.

With that in mind, we’re going to look at some of the most important IoT
protocols and standards that your business may use in 2023.

IoT Network Protocols

 Wi-Fi
 LTE CAT 1
 LTE CAT M1
 NB-IoT
  Bluetooth
 ZigBee
 LoRaWAN

IoT Data Protocols

 AMQP
 MQTT
 HTTP
 CoAP
 DDS
 LwM2M

Layers of the IoT Protocol Stack

"IoT protocol stack" refers to a hierarchy of software and hardware layers.

As Particle's Sr. Solutions Architect Dan Kouba phrased it, "It is all the things
that sit in between the data being produced at the edge to the data being
received by your systems."

The IoT network stack can be represented using the seven-layer OSI Network
Model, starting from the physical layer at the bottom and ending with the
application layer at the top. Specific protocols may represent only one layer or
span many—regardless, they must be interoperable to ensure that the network
functions as intended.
Next, let's take a closer look at each layer and its related functions.

1. The application layer, which encompasses the mobile and web

applications through which you might interact with the devices in an
IoT system.
2. The presentation layer, which encrypts and transforms data collected
by IoT devices so that the application layer can present the information
in a readable format.
3. The session layer, which acts as a kind of scheduler for incoming and
outgoing data. Whenever two devices need to communicate within an
IoT system, the system needs to schedule that communication by
opening a session.
4. The transport layer, which is like a fleet of trucks in a shipping
company, except that this layer transports packets of data instead of
shipping containers.
5. The network layer, which is like the post office for data, coordinating
where and when the system transfers data. Routers are the primary part
of the network layer that tell data packets how to get to their
destinations.
 6. The data link layer, which corrects errors due to abnormalities or
damaged hardware at the physical layer and links different devices so
they can transfer data through the network layer.
7. The physical layer, which is made up of ethernet cables, cell towers,
etc.

Physical and Data Link Layers

The first two layers from the bottom—the physical and data link layers—define
the physical connection of end devices to the network. More specifically:

 The physical layer receives unstructured raw data between devices and
physical transmission media, then transmits the digital information into
electrical, radio, or optical signals.
 The data link layer catches the data and detects/corrects any errors that
may have occurred. This layer also defines the protocol for flow control,
as well as establishing and terminating connections between two
physically connected devices.

"The physical layer is the actual hardware that the electronics are on," explained
Dan. "The data link layer represents how the modem negotiates with the cell
tower—for example, to establish a communication channel between a device
and the cell tower or other networking equipment."

Network, Transport, and Session Layers

The network, transport, and session layers facilitate data transfer over the
connection, with a focus on logical addressing, traffic directing, error
correction, flow control, congestion avoidance, session management, and
reliability.

"From the user’s perspective, these layers are the protocols that run on top of
the tunnel to facilitate communication," Dan noted. "What does that message
look like? How is it formulated? How do I put data in it? How do we get data
out of it?"

Presentation and Application Layers

The two layers at the top—presentation and application—deal with data

formatting and the boundary between the data coming from devices in the field
and a business application or database.
  The presentation layer transforms data into the form that is accepted by
the application.
 The application layer—the layer closest to the user—typically identifies
communication partners, determines resource availability, and
synchronizes communication.

At this point in the process, all procedures are accomplished over an encrypted
channel. Security applies to every layer in different ways and is often a function
of the protocol being used. Once the data reaches the cloud, the systems will
unpack it, analyze it, and make decisions accordingly before pushing each
decision to the user's cloud platform.

IoT Network Protocols: What Are They and What Do You Need to Know?

Wi-Fi

Wi-Fi is a ubiquitous protocol that can be found almost anywhere—industrial

plants, homes, commercial buildings, and even your neighborhood restaurants.
This widely favored technology is able to transmit large volumes of data over
reasonable distances. However, many low-power or battery-powered
IoT devices are unlikely to use Wi-Fi due to its high power consumption rate.

Read our in-depth comparison of cellular vs. WiFi for IoT applications to learn
more about when WiFi makes sense and when it doesn’t.

LTE CAT 1

LTE CAT 1 is a communication standard specifically designed for servicing

IoT applications. Compared with other standards, it scales down bandwidth and
communication demand to save power and cost for large-scale and long-range
IoT systems. Though LTE CAT 1 performs inferiorly to 3G networks, experts
predict that it will replace 3G as major U.S. carriers sunset 3G in 2022.

LTE CAT M1

LTE CAT M1—which can also be referred to as Cat-M—is a low-cost, low-

power, wide-area network that specializes in transferring low to medium
amounts of data. It was developed by the 3rd Generation Partnership Project as
part of the 13th edition of LTE standard and is a core cellular IoT technology.

Cat-M stands out as a protocol option because it is compatible with the

prevailing LTE network, meaning major carriers pivoting to it will not have to
invest in new antennas.
Comparison: CAT M1 is considered a complementary technology to NB
IoT. However, CAT M1 has a faster upload/download speed of 1 Mbps and
a lower latency of 10 to 15 ms.

NB-IoT

While the protocols detailed previously have been in application for a long time,
Narrow Band-IoT is a new, fast-growing, low-power, wide-area technology
intended to specifically target the needs of battery-powered IoT devices.

When compared to other cellular protocols, NB-IoT's advantages include

improvements in power consumption, system capacity, and spectrum efficiency.
For example, NB-IoT can connect huge fleets with up to 50,000 devices per
network cell.

However, NB-IoT doesn’t come without challenges. The protocol has very
limited bandwidth, which can slow or limit data transmission capabilities and
make essential features like over-the-air updates difficult or impossible to
achieve. Also, the protocol has seen limited rollout and support in worldwide
geographies. While support is growing, fragmented availability is a risk to any
IoT deployment.

Bluetooth

Bluetooth focuses on point-to-point, short-range communication of a relatively

small amount of data. In the IoT space, Bluetooth is commonly used to connect
small, battery-powered sensors to IoT gateways or to facilitate communication
with a smartphone, eBike, or other smart device.

ZigBee

Ratified in the early 2000s, ZigBee stands out as a low-cost, low-power, and
reliable wireless network technology. The standard is adaptable and supports
multiple network topologies, including mesh networks, point-to-multipoint, and
point-to-point. ZigBee is most commonly used in home or building automation
settings.

LoRaWAN

Long-range wide area network—also referred to as LoRa—is a long-range,

radio-wide networking protocol with low power consumption. Normally,
LoRaWAN wirelessly connects multiple battery-operated devices to the Internet
within regional, national, or global networks.
In the IoT field, LoRaWAN plays an important role in bidirectional
communication, end-to-end security, localization, and mobility services.

IoT Data Protocols: What Are They and What Do You Need to Know?

AMQP

Known for its reliability and interoperability, Advanced Message Queuing

Protocol is an open messaging standard. This protocol utilizes queues of data,
enabling connected systems to communicate asynchronously and better handle
issues like traffic spikes and poor network conditions.

Additional AMQP features include durable and persistent queues, federation

and high-availability queues, clustering, and flexible routing. However, AMQP
is known to be a verbose protocol in some circumstances.

Comparison: Compared with MQTT (discussed next), AMQP is more

reliable and secure.

MQTT

Message Queue Telemetry Transport is a lightweight pub/sub messaging

protocol suitable for connecting small, low-power devices.

This data protocol was designed specifically for IoT communication and
requires minimal memory and processing power. On the wire, MQTT's
bidirectional pub/sub architecture makes the protocol flexible and scalable for a
wide variety of use cases and IoT system architectures.

Additionally, the MQTT protocol is designed with reliability and scalability in

mind—security is provided via Transport Layer Security, and persistent
sessions allow the protocol to adapt to poor network conditions and reduce
connection time overhead.

HTTP

You might recognize this acronym as appearing at the beginning of every

website address you type, as Hypertext Transfer Protocol is the foundation of
data communication for the World Wide Web.

However, within the context of IoT applications, HTTP has many drawbacks.
For instance, this protocol establishes a synchronous connection between two
devices in order to transfer data—which presents a number of challenges for
IoT deployments because devices and endpoints may not be online at the same
time and connections may be unreliable due to network conditions.

Additionally, HTTP relies on transferring data in ASCII, which is an inefficient

way to transmit the small bits of data often exchanged by IoT systems and
requires more processing power to encode and decode messages at both ends.

Ultimately, while HTTP is a great choice for transferring website data, it is

generally not a good choice for an IoT application.

CoAP

Constrained Application Protocol is used with constrained nodes and networks.

This protocol is suited for IoT applications as it reduces the size of network
packages, thereby decreasing network bandwidth overload. Other benefits of
CoAP include improving the IoT life cycle, saving battery power and storage
space, and reducing the amount of data required to operate.

DDS

Released in 2004, Data Distribution Service is a middleware architecture for

real-time systems that focus on data communication between the nodes of a
publication- or subscription-based messaging architecture.

DDS is mainly used under circumstances that require real-time data exchange—
for example, autonomous vehicles, power generation, and robotics.

LwM2M

Lightweight Machine-to-Machine protocol is designed for remote management

of M2M devices and related services. LwM2M reduces costs associated with
low-power module deployment and equipping devices with faster IoT solutions.
Learn more about M2M vs IoT.

Comparison: Note that the CoAP, LwM2M client initiates the connection
to an LwM2M server that will use the REST API to manage the interfaces.

Why Are Protocols and Standards Important in IoT?

While this synopsis might seem like information overload, protocols are
essential in IoT implementations.

"You want to make sure that whatever language your computers are speaking is
really meant to be used for your use case," explained Dan. "There are lots of
ways to establish communication between two machines, and picking the right
one will give you advantages such as a low data rate."

Simply put, different protocols provide data in vastly different ways. For
example, video call protocols might deliver data in a specific order all the time
—something that's not necessarily guaranteed with other protocols—but may
not be able to ensure that low data is passed between devices.

IoT security is another important element to take into consideration, as

standardized IoT protocols can prevent further fragmentation and reduce the
risk of security threats.

"Security requires some exchange of information to establish a secure tunnel,

and doing that over certain protocols can be very data-intensive," said Dan.
"Using the IoT-based protocols leveraged by Particle minimizes this intensity."

How many IoT protocols are there?

In short, a lot. The IoT is heterogeneous, meaning that there are all sorts of
different smart devices, protocols, and applications involved in a typical IoT
system. Different projects and use cases might require different kinds of devices
and protocols.

For example, an IoT network meant to collect weather data over a wide area
needs a bunch of different types of sensors, and lots of them. With that many
sensors, the devices need to be lightweight and low-power, otherwise the energy
required to transmit data would be enormous. In such an instance, low-power is
the main priority, over, say, security or speed of transmission.

If, however, an IoT system consists of medical sensors on ambulances, sensors

that transmit patient data ahead to hospitals, time is clearly going to be of the
essence. What’s more, HIPAA requires special security protocols for health
data. So a higher-power, faster, and more secure protocol would be necessary.

Since there are so many different types of IoT systems and so many different
applications, experts have figured out a way to sort all the components of IoT
architecture into different categories, called layers. These layers allow IT teams
to home in on the different parts of a system that may need maintenance, as well
as to promote interoperability. In other words, if every system adheres to, or can
be defined by, a specific set of layers, the systems are more likely to be able to
communicate with each other through those layers.
One of the best frameworks for how you can understand IoT layers is the Open
Systems Interconnection (OSI) model, which defines seven different layers in a
top-down architecture. Top-down just means that the layers are defined starting
from what the typical person uses to interact with an IoT system, like a
smartphone app or website, and going down all the way to, for example, the
ethernet cables that work in the background to transmit data.

EFFORTS

IoT (Internet of Things) standardization is crucial for ensuring seamless

communication and interoperability among diverse IoT devices. Let’s delve into
some key aspects:
1. Fragmented Architectures:
o The current state of IoT standardization is marked by fragmented
architectures.
o There is no holistic approach to implementing IoT across various
sectors.
o Many isolated solutions exist, such as RFID and sensor networks,
but cross-sector technology reuse and knowledge exchange are
limited1.
2. M2M (Machine-to-Machine) and WSN (Wireless Sensor Network)
Protocols:
o M2M applications are often custom-built, lacking standardized
protocols.
o The M2M architecture includes fixed and non-cellular wireless
networks.
o Standardization efforts include:
 Data transport protocols (e.g., M2MXML, JSON, BiTXML,
WMMP, MDMP).
 Extending OMA DM (Device Management) to support
M2M devices.
 Standardizing M2M gateways, security, and fraud detection.
 Defining M2M service capabilities and open REST-based
APIs for applications1.
3. SCADA (Supervisory Control and Data Acquisition) and RFID
(Radio Frequency Identification) Protocols:
o SCADA represents a critical pillar in industrial automation.
o IEEE Std C37.1TM specifies SCADA and automation systems.
o Network-based industrial automation now leverages intelligent
electronic devices (IEDs), akin to IoT devices.
o M2M communication between devices has become essential.
o The restructuring of the electric industry has led to various entities
like GENCO, TRANSCO, DISCO, and ISO1.
 4. BACNet Protocol:
o BACNet is a communication protocol for Building Automation and
Control (BAC) networks.
o It facilitates information exchange among building automation
devices.
o BACNet supports applications such as HVAC control, lighting
control, access control, and fire detection systems.
o Key services include Who-Is, I-Am, Who-Has, and I Have for
device and object discovery.
o Read-Property and Write-Property services enable data sharing.
o BACNet defines multiple data link and physical layers, including
ARCNET, Ethernet, BACnet/IP, BACnet/IPv6, and ZigBee1.
5. Modbus Serial Protocol:
o Originally published by Modicon (now Schneider Electric) in
1979.
o Widely used for industrial automation and SCADA systems.
o Modbus facilitates communication between devices over serial
connections.
o It has become a de facto standard for connecting various devices in
industrial settings

M2M AND WSN PROTOCOLS

M2M: Machine-to-Machine Communications

One of the new technologies that’s part of the Internet of Things is Machine-to-
Machine (M2M) communications. M2M, though not well-defined, is a set of
methods and protocols to allow devices to communicate and interact over the
Internet (or other network) without human intervention. M2M is sometimes
considered to be low-overhead short-range wireless communication between
machines, utilizing protocols with much less overhead than full-blown TCP/IP.
Many M2M applications involve low power wireless devices with limited
computing power and narrowly-defined functionality. Low-overhead protocols
have been devised for them, including Message Queue Telemetry Transport
(MQTT), Constrained Application Protocol (CoAP), and Open Mobile Alliance
Light Weight M2M (OMA LWM2M). CoAP is actually a specialized web
transfer protocol designed for applications such as smart energy and building
automation. There is, of course, no reason why IoT devices cannot use high-
powered CPUs and wide bandwidth, and in many applications this is clearly
necessary, such as smart cars interacting with external servers. So IoT spans a
huge range from very simple low-powered specialized devices and sensors with
low bandwidth needs to complex, high-powered devices in large high-
bandwidth environments.

WSNs: Wireless Sensor Networks

IoT configurations often involve sensors, which can be connected by wireless

networks. Such sensor networks are termed “Wireless Sensor Networks” or
WSNs. A WSN comprises spatially distributed autonomous devices equipped
with sensors, connected through a wireless network to some type of gateway.
The sensors typically monitor physical or environmental conditions. The
gateway communicates with another set of devices that can act on the
information from the sensors. Application examples include patient monitoring;
environmental monitoring of air, water, and soil; structural monitoring for
buildings and bridges; industrial machine monitoring; and process monitoring.
The wireless network could be WiFi or Bluetooth, and the protocol one of the
three listed above.
The boundaries between these networks are not clearly drawn, and in practice
they overlap considerably. Figure 3 shows the relationship schematically:

Goals of IoT

In the short term, at least, the goals of IoT are straightforward

The objectives revolve around efforts to reduce costs and save time. But they
also promise to make new things possible that are not feasible now, such as
devices for improved patient monitoring and improved transportation systems
utilizing autonomous vehicles and other modes.

Wireless Sensor Network (WSN) is an infrastructure-less wireless network

that is deployed in a large number of wireless sensors in an ad-hoc manner that
is used to monitor the system, physical or environmental conditions.
Sensor nodes are used in WSN with the onboard processor that manages and
monitors the environment in a particular area. They are connected to the Base
Station which acts as a processing unit in the WSN System.
Base Station in a WSN System is connected through the Internet to share data.
WSN can be used for processing, analysis, storage, and mining of the data.
Applications of WSN:

1. Internet of Things (IoT)

2. Surveillance and Monitoring for security, threat detection
3. Environmental temperature, humidity, and air pressure
4. Noise Level of the surrounding
5. Medical applications like patient monitoring
6. Agriculture
7. Landslide Detection
Challenges of WSN:

1. Quality of Service
2. Security Issue
3. Energy Efficiency
4. Network Throughput
5. Performance
6. Ability to cope with node failure
7. Cross layer optimisation
8. Scalability to large scale of deployment
A modern Wireless Sensor Network (WSN) faces several challenges,
including:
 Limited power and energy: WSNs are typically composed of
battery-powered sensors that have limited energy resources. This
makes it challenging to ensure that the network can function for
long periods of time without the need for frequent battery
replacements.
 Limited processing and storage capabilities: Sensor nodes in a
WSN are typically small and have limited processing and storage
 capabilities. This makes it difficult to perform complex tasks or store
large amounts of data.
 Heterogeneity: WSNs often consist of a variety of different sensor
types and nodes with different capabilities. This makes it challenging
to ensure that the network can function effectively and
efficiently.
 Security: WSNs are vulnerable to various types of attacks, such as
eavesdropping, jamming, and spoofing. Ensuring the security of the
network and the data it collects is a major challenge.
 Scalability: WSNs often need to be able to support a large number of
sensor nodes and handle large amounts of data. Ensuring that the
network can scale to meet these demands is a significant
challenge.
 Interference: WSNs are often deployed in environments where there
is a lot of interference from other wireless devices. This can make it
difficult to ensure reliable communication between sensor nodes.
 Reliability: WSNs are often used in critical applications, such as
monitoring the environment or controlling industrial processes.
Ensuring that the network is reliable and able to function correctly
in all conditions is a major challenge.
Components of WSN:
1. Sensors:
Sensors in WSN are used to capture the environmental variables and
which is used for data acquisition. Sensor signals are converted into
electrical signals.
2. Radio Nodes:
It is used to receive the data produced by the Sensors and sends it to
the WLAN access point. It consists of a microcontroller, transceiver,
external memory, and power source.
3. WLAN Access Point:
It receives the data which is sent by the Radio nodes wirelessly,
generally through the internet.
4. Evaluation Software:
The data received by the WLAN Access Point is processed by a
software called as Evaluation Software for presenting the report to
the users for further processing of the data which can be used for
processing, analysis, storage, and mining of the data.

Advantages of Wireless Sensor Networks (WSN):

Low cost: WSNs consist of small, low-cost sensors that are easy to deploy,
making them a cost-effective solution for many applications.
Wireless communication: WSNs eliminate the need for wired connections,
which can be costly and difficult to install. Wireless communication also
enables flexible deployment and reconfiguration of the network.
Energy efficiency: WSNs use low-power devices and protocols to conserve
energy, enabling long-term operation without the need for frequent battery
replacements.
Scalability: WSNs can be scaled up or down easily by adding or removing
sensors, making them suitable for a range of applications and environments.
Real-time monitoring: WSNs enable real-time monitoring of physical
phenomena in the environment, providing timely information for decision
making and control.

Disadvantages of Wireless Sensor Networks (WSN):

Limited range: The range of wireless communication in WSNs is limited,

which can be a challenge for large-scale deployments or in environments with
obstacles that obstruct radio signals.
Limited processing power: WSNs use low-power devices, which may have
limited processing power and memory, making it difficult to perform complex
computations or support advanced applications.
Data security: WSNs are vulnerable to security threats, such as
eavesdropping, tampering, and denial of service attacks, which can
compromise the confidentiality, integrity, and availability of data.
Interference: Wireless communication in WSNs can be susceptible to
interference from other wireless devices or radio signals, which can degrade
the quality of data transmission.
Deployment challenges: Deploying WSNs can be challenging due to the need
for proper sensor placement, power management, and network configuration,
which can require significant time and resources.

SCADA AND RFID PROTOCOLS

SCADA (Supervisory Control and Data Acquisition) and RFID (Radio
Frequency Identification) protocols are two critical technologies that have
transformed various industries. SCADA systems allow for remote monitoring
and control of industrial processes in the oil and gas, energy, and manufacturing
industries. These systems collect data from sensors and deliver it in real-time to
human operators, allowing them to monitor and adjust the process as needed.

On the other hand, RFID is a wireless technology that communicates with tags
attached to objects via radio waves. These tags contain one-of-a-kind
identification codes that allow the system to track the object’s location,
movements, and other data. RFID has a wide range of applications, including
supply chain management, inventory control, and security and access control.

SCADA and RFID technologies have significantly improved industrial

processes, making them more efficient, safe, and secure. We can expect even
more advancements and opportunities in the future as these technologies
continue to evolve.

Introduction to SCADA and RFID Protocols: Key Concepts and

Applications

Both Supervisory Control and Data Acquisition (SCADA) and Radio Frequency
Identification (RFID) protocols are widely used in a variety of industries.
SCADA is a system that allows operators to remotely monitor and control
industrial processes, whereas RFID is a wireless technology used for object
tracking and identification.

SCADA systems collect data from sensors installed in the process and transmit
it to a central control system via communication protocols. This data is then
analyzed to provide human operators with real-time information, allowing them
to make informed decisions and remotely control the process. SCADA systems
are used in many industries, including oil and gas, water treatment, energy, and
manufacturing.

RFID, on the other hand, communicates with tags attached to objects using
radio waves. These tags have a unique identification code that RFID readers can
read, allowing the system to track the object’s location, movement, and other
data. RFID is widely used in inventory management, asset tracking, access
control, and security applications.

The integration of SCADA and RFID technologies has given industrial

environments a new level of visibility and control. Operators can quickly
identify issues and take action to prevent further problems by using RFID to
track objects and SCADA to monitor and control the process. Due to this
integration, businesses have been able to optimize their operations, reduce
downtime, and improve safety and security.

The combination of SCADA and RFID protocols has given industries powerful
tools for increasing efficiency, productivity, and safety. We can expect to see
even more innovative applications in the future as these technologies continue
to evolve.
Understanding SCADA Protocols: Communication and Control Systems

SCADA (Supervisory Control and Data Acquisition) protocols are used in

industrial processes to enable communication and control. Sensors, controllers,
and communication devices are among the components of a SCADA system.
The SCADA protocols used to control and communicate with these components
are critical for ensuring that industrial processes run efficiently and safely.

SCADA communication protocols are used to transfer data between SCADA

system components. Modbus, DNP3 (Distributed Network Protocol), and IEC
60870-5 are the most common communication protocols used in SCADA
systems. These protocols define the structure of the data being transmitted, the
type of data, and the method of data transfer.

Control protocols are used to manage the various components of a SCADA

system. OPC (OLE for Process Control), BACnet (Building Automation and
Control Networks), and SNMP are the most common control protocols used in
SCADA systems (Simple Network Management Protocol). These protocols are
used to configure devices, set and adjust system parameters, and manage alarms
and events.

SCADA systems allow for remote monitoring and control of industrial

processes while providing real-time data to human operators. These systems are
used in various industries, including energy and water treatment, manufacturing,
and transportation. SCADA protocols allow these systems to operate
seamlessly, ensuring the process’s efficiency and safety.

Understanding SCADA protocols is critical for ensuring that industrial

processes run efficiently and safely. Properly selecting and implementing
communication and control protocols are critical for a SCADA system’s
integrity. SCADA systems are poised to continue revolutionizing industries and
providing critical support for industrial processes as new protocols, and
technological advancements emerge.

RFID Protocols: Types and Standards for Identification and Tracking

RFID (Radio Frequency Identification) protocols identify and track objects

using radio waves. RFID protocols of various types and standards are used in
various industries for various applications.
The most common RFID protocols are low-frequency (LF), high-frequency
(HF), and ultra-high-frequency (UHF). LF RFID operates at a frequency of 125-
134 kHz and is used for short-range communication, typically up to 10 cm. HF
RFID operates at a frequency of 13.56 MHz and is used for short- to medium-
range communication (up to 1 meter). UHF RFID operates at a frequency range
of 860-960 MHz and is used for long-range communication up to several
meters.

Aside from these, several RFID standards are used for identification and
tracking. The most widely used standards for HF RFID are ISO 14443 and ISO
15693, and ISO 18000-6c for UHF RFID. These standards specify the RFID
system’s frequency, data rate, and encoding. They also define the RFID tag’s
data structure, including the identification number, manufacturer code, and
other pertinent information.

RFID protocol and standard implementation vary depending on the application.

For example, LF RFID is commonly used in animal identification, whereas HF
RFID is used in access control, payment systems, and inventory management.
UHF RFID is used in supply chain management, asset tracking, and other
applications that require long-range communication.

RFID protocols and standards are critical in identifying and tracking objects
across industries. The appropriate protocol and standard are chosen based on the
specific application requirements. RFID is poised to continue revolutionizing
industries and enabling a new level of visibility and control as technology
advances, and new standards emerge.

SCADA Security: Protecting Industrial Control Systems from Cyber

Threats

SCADA (Supervisory Control and Data Acquisition) systems are used in

industrial settings to monitor and control critical processes, making them
vulnerable to cyber-attacks. SCADA systems are frequently linked to other
systems and networks, posing potential security risks.

SCADA security entails safeguarding industrial control systems against cyber

threats that could cause disruptions, sabotage, or other types of attacks. There
are two types of cyber threats to SCADA systems: external and internal.
External threats come from outside the organization, whereas internal threats
come from within the organization.
Security measures that ensure data confidentiality, integrity, and availability
must be implemented to protect SCADA systems from cyber threats. One
important measure is to use strong access controls, such as multi-factor
authentication and role-based access controls, to limit access to sensitive
information and systems. In addition to monitoring network traffic and
detecting anomalies that may indicate a security breach, firewalls, and intrusion
detection systems can be used.

Another important precaution is to keep software and hardware systems up to

date, as outdated systems can create vulnerabilities that cyber attackers can
exploit. Regular security audits, penetration testing and vulnerability scans can
assist in identifying and correcting security flaws in SCADA systems.

Furthermore, user training and awareness can be critical in helping employees

understand the risks and best practices for safely and securely using SCADA
systems. This includes educating employees on social engineering attacks,
phishing, and other common cyber-attack tactics.

Safeguarding SCADA systems against cyber threats is critical to ensuring the

safe and efficient operation of industrial processes. Strong access controls,
current software and hardware, and regular security assessments are critical
measures for protecting SCADA systems from external and internal cyber
threats. Organizations can reduce the risk of cyber attacks on their SCADA
systems by implementing these measures and fostering a culture of security
awareness.

RFID and SCADA Integration: Enhancing Visibility and Control in

Industrial Environments

In industrial environments, the integration of RFID (Radio Frequency

Identification) and SCADA (Supervisory Control and Data Acquisition)
systems can improve visibility and control over critical processes, assets, and
inventory. RFID identifies and tracks objects in real-time, whereas SCADA
monitors and controls industrial processes.

RFID and SCADA system integration can provide a variety of benefits,

including increased accuracy, efficiency, and productivity. RFID tags can be
attached to assets or inventory, allowing for real-time tracking and monitoring,
and SCADA can use this data to optimize processes, reduce downtime, and
improve overall efficiency.
RFID and SCADA integration can improve security by providing real-time
alerts when unauthorized access is detected, in addition to tracking and
monitoring. RFID tags can also be used to identify employees and track their
movements, preventing access to restricted areas and increasing safety.

Furthermore, integrating RFID and SCADA can improve supply chain

management by providing real-time visibility into the movement and status of
goods from production to delivery. This allows for better decision-making and
can aid in cost reduction and customer satisfaction.

However, integrating RFID and SCADA systems requires careful planning and
execution to ensure that they work effectively and securely together. A thorough
assessment of the organization’s needs and an evaluation of the available
technologies, standards, and protocols should be part of the integration process.

When integrating RFID and SCADA systems, security should be a top priority.
This includes enforcing strict access controls, encrypting data, and conducting
regular security audits to identify and address vulnerabilities.

Integrating RFID and SCADA systems can provide significant benefits to

industrial organizations, such as improved visibility, control, efficiency, and
security. However, careful planning and implementation are required to ensure
that the systems work effectively and securely together. Organizations can
improve their operations and gain a competitive advantage in the market by
integrating RFID and SCADA systems.

SCADA and RFID in Smart Manufacturing: Advancements and

Challenges

In smart manufacturing environments, the integration of SCADA (Supervisory

Control and Data Acquisition) and RFID (Radio Frequency Identification)
technologies can lead to significant advancements in automation, efficiency,
and productivity. Smart manufacturing optimizes industrial processes and
improves performance by leveraging technologies such as the Internet of Things
(IoT), artificial intelligence (AI), and machine learning (ML).

In smart manufacturing environments, SCADA and RFID technologies can

provide real-time monitoring, control, and automation of industrial processes.
RFID tags are useful for identifying and tracking inventory and assets, whereas
SCADA systems are useful for monitoring and controlling critical processes
like temperature, pressure, and flow rate.
The integration of SCADA and RFID technologies in smart manufacturing
environments has the potential to improve automation, efficiency, and
productivity significantly. Real-time data from RFID tags, for example, can be
used to optimize production lines, reduce waste, and improve overall efficiency.
SCADA systems can also be used to automate routine tasks like quality control
and maintenance, allowing personnel to focus on more difficult tasks.

However, integrating SCADA and RFID technologies in smart manufacturing

environments is fraught with difficulties. One major challenge is ensuring data
privacy and security. The increased use of IoT and other connected devices
raises the risk of cyber-attacks and data breaches. As a result, it is critical to put
in place strong security measures such as data encryption, multi-factor
authentication, and regular security audits.

Another difficulty is the requirement to integrate multiple systems and

technologies. Smart manufacturing environments frequently employ various
technologies and platforms that are not always designed to work in tandem. As
a result, it is critical to ensure that the various systems are compatible and
capable of communicating effectively.

The integration of SCADA and RFID technologies in smart manufacturing

environments has the potential to improve automation, efficiency, and
productivity significantly. However, it presents several challenges, including the
need to ensure data privacy and security and the integration of multiple systems
and technologies. Organizations can gain a competitive advantage in the
marketplace and improve their operations by addressing these challenges and
leveraging the full potential of these technologies.
 UNIFIED DATA STANDARDS

Unified data standards in IoT are foundational elements that ensure

compatibility, consistency, and interoperability in the vast ecosystem of
connected devices, sensors, and systems. These standards establish a common
language and framework for organising and interpreting data, enabling seamless
communication and integration across various sources and applications.
In the context of IoT, where devices come from different manufacturers, use
various communication protocols, and have diverse data formats, UDS are
essential for facilitating efficient data exchange and integration. By following
common data formats and protocols, IoT devices can transmit and receive
information in a standardised manner, regardless of their origin. This allows for
the seamless integration of data from multiple sources, enabling comprehensive
analysis, decision-making, and automation.
UDS also promote interoperability by enabling different devices to understand
and interpret data from each other. When IoT devices adhere to the same
standards, they can communicate effectively, regardless of their underlying
technologies or manufacturers. This interoperability allows for the creation of
IoT ecosystems where devices from various vendors can seamlessly work
together, enhancing the scalability and flexibility of IoT deployments.
Data consistency and quality are other crucial aspects addressed by UDS. These
standards establish rules for data structure, naming conventions, units of
measurement, and other aspects, ensuring consistency and uniformity in the way
data is captured, represented, and stored. By adhering to these standards, IoT
devices generate high-quality data that can be easily understood, analyzed, and
shared across different applications and systems.
Furthermore, unified data standards provide a foundation for scalable IoT
deployments. As the IoT landscape evolves and new devices and technologies
emerge, data standards help future-proof IoT systems by ensuring backward
compatibility and enabling seamless integration of new devices into existing
infrastructures. This scalability allows organisations to expand their IoT
networks without encountering major compatibility issues or costly redesigns.
Data security and privacy are also critical considerations in IoT deployments.
Unified data standards contribute to data security and privacy by implementing
standardised security protocols and encryption methods. These measures protect
data during transmission and storage. Data standards also enable consistent
implementation of privacy regulations and data governance policies, ensuring
that personal and sensitive information is handled in a standardised and secure
manner.

Exploring the Diverse Types of Unified Data Standards in IoT

There are various types of standards that play a crucial role in facilitating
interoperability and seamless communication between devices. These standards
cover different aspects of data exchange, integration, and interpretation. Let’s
delve into some key types of unified data standards in IoT:
Communication Protocols:

 MQTT (Message Queuing Telemetry Transport): MQTT is a lightweight

messaging protocol that enables efficient communication between IoT
devices and servers. It supports publish-subscribe messaging patterns and
is widely used in IoT deployments.

 CoAP (Constrained Application Protocol): CoAP is designed for

resource-constrained devices and allows for simple and low-overhead
communication over the Internet. It is often used in IoT applications
where devices have limited resources.

 OPC UA (Unified Architecture): OPC UA is an open, platform-

independent communication protocol that enables secure and reliable data
exchange between industrial automation systems and IoT devices. It is
widely used in industrial IoT applications.

Data Format Standards:

  JSON (JavaScript Object Notation): JSON is a lightweight and widely
adopted data interchange format that uses a human-readable text format
to transmit structured data. It is commonly used in web-based IoT
applications.

 XML (eXtensible Markup Language): XML is a flexible markup

language that defines rules for encoding documents in a format that is
both human-readable and machine-readable. It is widely used in various
IoT applications.

 CSV (Comma-Separated Values): CSV is a simple and widely

supported file format that stores tabular data as plain text, with each line
representing a data record and fields separated by commas. It is
commonly used for data exchange and integration in IoT applications.

Semantic Standards:

 RDF (Resource Description Framework): RDF is a framework for

describing resources on the web, using subject-predicate-object triples to
represent and link data. It facilitates interoperability between different
data sources and is often used in IoT applications that require semantic
interoperability.

 OWL (Web Ontology Language): OWL is a language for defining

ontologies, which provide a shared vocabulary for describing entities,
relationships, and constraints in a specific domain. It is widely used in
IoT applications that require semantic representation and reasoning.

Metadata Standards:

 Schema.org: Schema.org is a collaborative initiative by major search

engines to provide a standardised vocabulary for structured data markup
on web pages. It improves the visibility and interpretability of IoT-related
information and is widely used in web-based IoT applications.

 O-MI (Open Messaging Interface): O-MI is a standard for exchanging

information about objects and their relationships, enabling
 interoperability between IoT platforms. It is often used in IoT
applications that require real-time data exchange.

Security and Privacy Standards:

 TLS (Transport Layer Security): TLS is a cryptographic protocol that

ensures secure communication and data integrity between IoT devices
and servers over the network. It is widely used in IoT applications that
require secure data transmission.

 OAuth (Open Authorization): OAuth is a protocol for secure

authorization and delegated access control, enabling IoT devices to obtain
authorised access to resources. It is commonly used in IoT applications
that require secure access control.

 GDPR (General Data Protection Regulation): GDPR is a regulation that

defines rules for the protection of personal data and privacy of individuals
within the European Union. It impacts IoT data handling and storage
practices, ensuring compliance with privacy regulations.

These are just a few examples. Depending on the specific requirements of IoT
applications, different standards may be adopted to ensure interoperability, data
consistency, security, and privacy.
Addressing the Imperative Need for Unified Data Standards in IoT
The growing complexity and interconnectedness of IoT systems have
highlighted the need for UDS. Without standardised data formats, protocols,
and interoperability guidelines, IoT deployments face numerous challenges. So,
what are some problems that UDS can solve?
Fragmented Data Landscape:
The proliferation of diverse devices, platforms, and protocols has resulted in a
fragmented data landscape in IoT. Without UDS, IoT deployments face
compatibility issues and encounter data silos. Integrating and exchanging data
across different systems becomes difficult, hindering comprehensive analysis
and decision-making.
Interoperability Challenges:
The lack of standardised communication protocols and data formats poses
significant challenges to interoperability in IoT. Inefficient data exchange and
limited interoperability between devices hinder seamless communication and
collaboration. Achieving seamless interoperability becomes a barrier to the
widespread adoption and scalability of IoT deployments.
Data Inconsistency and Integrity:
Variations in data structures, semantics, and interpretations create data
inconsistencies and integrity issues in IoT. Inconsistent data quality,
inconsistencies, and errors impact decision-making, analytics, and automation
processes. Adhering to UDS ensures data consistency and integrity, enabling
accurate analysis and decision-making.
Scalability and Future-Proofing:
Scalability is a pressing concern for IoT deployments. Heterogeneous data
standards pose challenges in scaling IoT deployments. Integrating new devices
and technologies becomes difficult, hindering the expansion of IoT networks.
UDS provide a foundation for scalable IoT deployments, ensuring backward
compatibility and seamless integration of new devices.
Integration and Data Analytics:
Complex integration processes between disparate systems pose challenges in
IoT deployments. Higher costs and delays in data analysis and insights hinder
innovation and the development of IoT applications. Unified data standards
optimise integration processes, reduce costs, and enable efficient data analysis,
fostering innovation and development.
Security and Privacy Concerns:
Inconsistent security measures across different data standards pose significant
security and privacy concerns in IoT. Ensuring consistent implementation of
security protocols, encryption methods, and privacy regulations becomes
challenging without unified data standards. Implementing unified data standards
enhances data security and privacy compliance, mitigating risks of unauthorised
access and data breaches.
Industry Collaboration and Market Growth:
Collaboration among stakeholders is crucial for the development and adoption
of unified data standards. The importance of collaboration and consensus
among stakeholders cannot be overstated. Collaborative efforts lead to the
standardisation of data formats, protocols, and interoperability guidelines,
enabling market growth and innovation in IoT. Unified data standards benefit
businesses, consumers, and the IoT ecosystem as a whole.

PROTOCOLS

Unified data standards and protocols are important in the IoT realm. Standard
protocols define rules and formats for setting up and managing IoT networks,
along with how data are trans

Unified Data Standards (UDS) play a crucial role in the vast ecosystem of
the Internet of Things (IoT). Let’s delve into their significance and impact:
1. Concept and Purpose of UDS in IoT:
 o Unified data standards refer to guidelines, rules, or specifications
that govern the format, structure, and meaning of data
exchanged between different IoT systems, devices, or platforms.
o These standards establish a common language and
framework for organizing and interpreting data, enabling seamless
communication and integration across various sources and
applications.
o In the context of IoT, where devices come from different
manufacturers, use various communication protocols, and have
diverse data formats, UDS are essential for facilitating efficient
data exchange and integration.
o By adhering to common data formats and protocols, IoT devices
can transmit and receive information in a standardized manner,
regardless of their origin. This allows for the seamless integration
of data from multiple sources, enabling comprehensive analysis,
decision-making, and automation.
2. Benefits of UDS in IoT:
o Interoperability: UDS promote interoperability by enabling
different devices to understand and interpret data from each other.
When IoT devices adhere to the same standards, they can
communicate effectively, regardless of their underlying
technologies or manufacturers. This interoperability allows for the
creation of IoT ecosystems where devices from various vendors
can seamlessly work together, enhancing the scalability and
flexibility of IoT deployments.
o Data Consistency and Quality: UDS establish rules for data
structure, naming conventions, units of measurement, and other
aspects, ensuring consistency and uniformity in the way data is
captured, represented, and stored. High-quality data generated by
adhering to these standards can be easily understood, analyzed, and
shared across different applications and systems.
o Security and Privacy: Unified data standards contribute to data
security and privacy by implementing standardized security
protocols and encryption methods. These measures protect data
during transmission and storage. Data standards also enable
consistent implementation of privacy regulations and data
governance policies, ensuring that personal and sensitive
information is handled appropriately.
3. Real-World Implementation Challenges:
o Despite the benefits, implementing UDS in IoT faces challenges
such as varying industry requirements, legacy systems, and the
need for collaboration among stakeholders.
 o However, efforts by organizations, standard bodies, and industry
consortia continue to drive the adoption of UDS, aiming for a more
connected, efficient, and secure IoT landscape.

IEEE 802.15.4

IEEE 802.15.4 is a low-cost, low-data-rate wireless access technology for

devices that are operated or work on batteries. This describes how low-rate
wireless personal area networks (LR-WPANs) function.

IEEE 802.15.4e:

802.15.4e for industrial applications and 802.15.4g for the smart utility
networks (SUN)
The 802.15.4e improves the old standard by introducing mechanisms such as
time slotted access, multichannel communication and channel hopping.
 IEEE 802.15.4e introduces the following general functional
enhancements:
1. Low Energy (LE): This mechanism is intended for applications that can
trade latency for energy efficiency. It allows a node to operate with a very
low duty cycle.
2. Information Elements (IE) It is an extensible mechanism to exchange
information at the MAC sublayer.
3. 3. Enhanced Beacons (EB): Enhanced Beacons are an extension of the
802.15.4 beacon frames and provide a greater flexibility. They allow to
create application-specific frames.
4. 4. Multipurpose Frame: This mechanism provides a flexible frame format
that can address a number of MAC operations. It is based on IEs.
5. 5. MAC Performance Metric: It is a mechanism to provide appropriate
feedback on the channel quality to the networking and upper layers, so that
appropriate decision can be taken.
6. 6. Fast Association (FastA) The 802.15.4 association procedure introduces
a significant delay in order to save energy. For time-critical application
latency has priority over energy efficiency.
IEEE 802.15.4e defines five new MAC behavior modes.

1. Time Slotted Channel Hopping (TSCH): It targets application domains such

as industrial automation and process control, providing support for multi-hop
and multichannel communications, through a TDMA approach.
2. Deterministic and Synchronous Multi-channel Extension (DSME): It is
aimed to support both industrial and commercial applications.
 3. Low Latency Deterministic Network (LLDN): Designed for single-hop and
single channel networks
4. Radio Frequency Identification Blink (BLINK): It is intended for
application domains such as item/people identification, location and tracking.
5. Asynchronous multi-channel adaptation (AMCA): It is targeted to
application domains where large deployments are required, such as smart
utility networks, infrastructure monitoring networks, and process control
networks.

Properties:

1. Standardization and alliances: It specifies low-data-rate PHY and MAC

layer requirements for wireless personal area networks (WPAN).
IEEE 802.15. Protocol Stacks include:
 ZigBee: ZigBee is a Personal Area Network task group with a low
rate task group 4. It is a technology of home networking. ZigBee is a
technological standard created for controlling and sensing the
network. As we know that ZigBee is the Personal Area network of
task group 4 so it is based on IEEE 802.15.4 and is created by Zigbee
Alliance.
 6LoWPAN: The 6LoWPAN system is used for a variety of
applications including wireless sensor networks. This form of
wireless sensor network sends data as packets and uses IPv6 –
providing the basis for the name – IPv6 over Low power Wireless
Personal Area Networks.
 ZigBee IP: Zigbee is a standards-based wireless technology that was
developed for low-cost and low-power wireless machine-to-machine
(M2M) and internet of things (IoT) networks.
 ISA100.11a: It is a mesh network that provides secure wireless
communication to process control.
 Wireless HART: It is also a wireless sensor network technology,
that makes use of time-synchronized and self-organizing architecture.
 Thread: Thread is an IPv6-based networking protocol for low-power
Internet of Things devices in IEEE 802.15. 4-2006 wireless mesh
network. Thread is independent.
2. Physical Layer: This standard enables a wide range of PHY options in ISM
bands, ranging from 2.4 GHz to sub-GHz frequencies. IEEE 802.15.4 enables
data transmission speeds of 20 kilobits per second, 40 kilobits per second, 100
kilobits per second, and 250 kilobits per second. The fundamental structure
assumes a 10-meter range and a data rate of 250 kilobits per second. To further
reduce power usage, even lower data rates are possible. IEEE 802.15.4
regulates the RF transceiver and channel selection, and even some energy and
signal management features, at the physical layer. Based on the frequency
range and data performance needed, there are now six PHYs specified. Four of
them employ frequency hopping techniques known as Direct Sequence Spread
Spectrum (DSSS). Both PHY data service and management service share a
single packet structure so that they can maintain a common simple interface
with MAC.
3. MAC layer: The MAC layer provides links to the PHY channel by
determining that devices in the same region will share the assigned
frequencies. The scheduling and routing of data packets are also managed at
this layer. The 802.15.4 MAC layer is responsible for a number of functions
like:
 Beaconing for devices that operate as controllers in a network.
 used to associate and dissociate PANs with the help of devices.
 The safety of the device.
 Consistent communication between two MAC devices that are in a
peer-to-peer relationship.
Several established frame types are used by the MAC layer to accomplish
these functions. In 802.15.4, there are four different types of MAC frames:
 frame of data
 Frame for a beacon
 Frame of acknowledgement
 Frame for MAC commands
4. Topology: Networks based on IEEE 802.15.4 can be developed in a star,
peer-to-peer, or mesh topology. Mesh networks connect a large number of
nodes. This enables nodes that would otherwise be out of range to interact with
each other to use intermediate nodes to relay data.
5. Security: For data security, the IEEE 802.15.4 standard employs the
Advanced Encryption Standard (AES) with a 128-bit key length as the basic
encryption technique. Activating such security measures for 802.15.4
significantly alters the frame format and uses a few of the payloads. The very
first phase in activating AES encryption is to use the Security Enabled field in
the Frame Control part of the 802.15.4 header. For safety, this field is a single
bit which is assigned to 1. When this bit is set, by taking certain bytes from its
Payload field, a field known as the Auxiliary Security Header is formed
following the Source Address field.
6. Competitive Technologies: The IEEE 802.15.4 PHY and MAC layers
serve as a basis for a variety of networking profiles that operate in different
IoT access scenarios. DASH7 is a competing radio technology with distinct
PHY and MAC layers.
The architecture of LR-WPAN Device:

Applications of IEEE 802

IEEE 802.15.4 technology finds numerous applications in various fields,

including industrial automation, smart energy, healthcare, home automation,
and environmental monitoring and control.

 Industrial Automation − This section highlights how IEEE 802.15.4

technology is an integral part of industrial automation and how wireless
sensor networks utilizing IEEE 802.15.4 Technology can support a range
of applications such as asset tracking, temperature control, and predictive
maintenance.
 Smart Energy − This section discusses how IEEE 802.15.4 technology
enables remote control, monitoring, and management of energy
consumption by using smart meters and sensors, resulting in better
demand management, lower costs, and prevention of blackouts.
 Healthcare − This section discusses how IEEE 802.15.4 technology
enables remote patient monitoring systems, facilitates telemedicine
services for remote diagnosis and treatment of various illnesses, and
enables seamless communication between different medical devices like
insulin pumps, pacemakers, and cardiac monitors.
 Home Automation − This section explains how IEEE 802.15.4
technology impacts home automation, allowing homeowners to have
 remote control over different devices in their homes, making life more
comfortable, convenient, and secure.
 Environmental Monitoring and Control − This section highlights how
IEEE 802.15.4 technology enables wireless sensor networks to monitor
various environmental parameters like temperature, humidity, air quality,
water quality, etc., and provide real-time data for analysis and effective
control of the environment.

Benefits of IEEE 802

IEEE 802.15.4 technology offers benefits such as low power consumption and
extended battery life, low cost and simple implementation, limited data
transmission rate, and limited range and interference.

 Low Power Consumption and Extended Battery Life

 Low Cost and Simple Implementation
 Limited Data Transmission Rate
 Limited Range and Interference
Low power consumption and extended battery life
 Achieved through limiting data transmission and implementing energy-
efficient communication protocols.
 Crucial in IoT and industrial settings where frequent battery replacements
are impractical and costly.
 Popular choice for device manufacturers looking to provide extended
battery life while maintaining reliable wireless connectivity.
Low Cost and Simple Implementation
 Requires very little hardware compared to other wireless protocols.
 Easy to implement in a variety of applications without requiring extensive
technical expertise or specialized equipment.
 Lucrative option for a wide range of applications where budget
constraints and simplicity are important considerations.
Limited Data Transmission Rate
 Intentional design choice to balance power consumption with data
transfer needs.
 More than enough for applications that require periodic sensing and
reporting of small amounts of data.
 Reduces network congestion and interference between devices in a given
network, making it ideal for building reliable wireless sensor networks
(WSNs).
Limited Range and Interference
 Maximum range of around 30 meters, limiting its use in larger facilities
or outdoor settings.
 2.4 GHz frequency band used can experience interference from other
devices such as Wi-Fi routers and microwave ovens.
 Still has plenty of applications in industrial settings where a smaller range
is suitable, such as environmental monitoring systems within a factory or
warehouse setting.
Comparison With ZigBee, Wi-Fi, And Bluetooth
 Best suited for applications requiring very low power consumption,
limited data transmission rates, and a moderate range.
 Ideal choice for industrial applications where energy efficiency and
reliability are of utmost importance.

Types of devices in IEEE 802.15.4 Technology

IEEE 802.15.4 technology includes various types of devices that can be used for
wireless communication and networking. These devices are −

 Coordinator − This device is responsible for initiating the PAN

(Personal Area Network) and managing the network.
 Full Function Device (FFD) − This device has the ability to act as a
coordinator or a router, and can also host other devices.
 Reduced Function Device (RFD) − A device that can only communicate
with FFDs, but not capable of hosting other devices or working as a
coordinator.
 Sensor Node − This device includes sensor modules for monitoring
physical parameters such as temperature, humidity, pressure, etc., and
transmit data wirelessly to the receiver.
 Actuator Node − This device receives information sent by the controller
node and performs actions accordingly to control actuators such as
motors, pumps, valves, etc.
 Gateway Node − A bridge between different networks to exchange data
using different protocols such as Wi-Fi or Ethernet.
 Repeater Node − A device that retransmits data packets from one node
to another in order to extend the range of network coverage.
Advantages of IEEE 802.15.4:

IEEE 802.15.4 has the following advantages:

 cheap cost
 long battery life,
 Quick installation
 simple
 extensible protocol stack

Disadvantages of IEEE 802.15.4:

IEEE 802.15.4’s drawbacks include:

 IEEE 802.15.4 causes interference and multipath fading.
 doesn’t employ a frequency-hopping approach.
 unbounded latency
 interference susceptibility

BACNet PROTOCOL
BACnet protocol was developed by a committee named ASHRAE or the
American Society of Heating, Refrigerating & Air-Conditioning Engineers in
1987. The main motto of this committee is to make a protocol that would
provide systems from various manufacturers to communicate together in a
pleasant way. So this protocol is a registered brand of ASHRAE. Since the time
protocol was developed it is undergoing continuous changes with an open
agreement procedure. So that all interested parties are welcome to participate
with no fees. So this article discusses an overview of Bacnet Protocol basics –
working with applications.
What is BACnet Protocol?

A data communication protocol that is used to build an automated control

network, is known as BACnet or Building Automation Control Network. This
data communication protocol is both an ISO & ANSI standard used for
interoperability between cooperating building automation devices. Bacnet
Protocol includes a set of rules for governing the data exchange on a computer
network that simply covers all from what type of cable to utilize, to form a
particular command or request in a normal way.
To attain interoperability across a broad spectrum of equipment, the BACnet
specification includes three major parts. Primary, Secondary, and tertiary. So
the primary part defines a technique to represent any kind of building
automation apparatus in a normal way.
The secondary part describes messages that can be transmitted across a network
of computers to check and manage such equipment. The final part describes a
set of suitable LANs which are used for conveying BACnet communications.

Why is Bacnet Protocol required?

The BACnet protocol’s importance is to define typical techniques that

manufacturers can execute to build components as well as systems that are
interoperable through other components & systems of BACnet.
It also specifies how data is signified on the network as well as the services that
are utilized to transmit data from one node of BACnet to another node. It also
has messages that recognize network & data nodes.

BACnet is used as a tool by owners of buildings & system specifiers for the
specification of the interoperable system. This protocol does not change the
need for indicating what a consumer needs. So, it provides simply some
consistent tools to assist the creation & specification of systems that can
interoperate.

BACnet protocol is used in all types of automated building systems. So, there
are interoperable products available within different categories like security,
fire, lighting, elevators, HVAC, etc. This protocol simply addresses the
interoperability goal through simply defining a general working model of
automation devices, a technique used for defining the data that they include, &
also a technique used for explaining protocols that a single device can utilize to
inquire one more device to execute some preferred action.

Bacnet Protocol Architecture

The BACnet protocol architecture is predominately restricted to lighting

controls, HVAC & gateways. This protocol highlights lightweight and efficient
communication which is optimized for short messages, small networks, and
inter-networks.
BACnet protocol architecture is a collapsed architecture that matches to 4-layers
of the OSI model. The four layers in the BACnet architecture mainly include
Application, Network, Data Link & Physical. Even though, just the Network
layer & Application layer are simply BACnet.
The above architecture is the BACnet protocol stack which includes different
layers as shown in the diagram. This protocol is a collapsed version of the OSI
stack. The transport and session layers are not used. The application layer takes
on the functions of these two layers.

BACnet Physical Layer

The upper layers of BACnet do not depend on the physical layer. So the
Physical layer of BACnet makes it feasible for BACnet to be executed on
different networks. The physical layers of BACnet have been specified with
ARCNET, Ethernet, IP tunnels, BACnet/IP, RS-232, RS485, and
Lonworks/LonTalk. RS232 is for point-to-point communication. RS485
supports up to 32 nodes with a distance of 1200 m at 76Kbps.

BACnet Protocol Link Layer

BACnet protocol is implemented directly with LonTalk or IEEE802.2 link

layers. So it specifies Point to Point (PTP) data link layer for RS232
connections. It specifies MS/TP data link layer intended for RS-485
connections. The standard simply specifies BVLL (BACnet Virtual Link Layer)
which states all the services required through the BACnet device at this link
layer.
IP BACnet Virtual Link Layer encapsulates required control data in a header of
BACnet virtual link control information. Because of IP, BVLL, and BACnet
protocol devices can directly communicate over IP networks without the
requirement of any router device.

BACnet protocol utilizes BBMD (BACnet broadcast management device)

concept which executes the required broadcast for the preferred link layer. So,
the BACnet broadcast message is changed into IP-based broadcast or multicast
messages.

BACnet Network Layer

This layer simply specifies the required addresses of the network for routing.
BACnet network includes a minimum of one or above segments that are
connected with bridges once they utilize similar LAN technologies. If they
utilize various LAN protocols then they are connected through routers.

Application Layer

BACnet does not separate presentation as well as application layers. So it takes

care of reliability & sequencing or segmentation mechanisms generally
connected with both the session & transport layers. BACnet includes devices
like objects to exchange service primitives which are described with ASN.1
syntax & serialized with ASN.1 BER.

BACnet Security Layer

The concept of BACnet security can be understood easily with an example say
when BACnet device-A requests a session key from the key server for
establishing secure communication through device-B, then this key is
transmitted to both the device-A & device-B through the key server which is
known as ‘SKab’. BACnet protocol uses 56-bit DES encryption.

How Does Bacnet Protocol Work?

BACnet is a typical electronic communication protocol that works by allowing

different kinds of manufacturers’ building automation as well as monitoring
systems like fire alarms, HVAC, and perimeter security for communicating with
each other. This protocol can work with nearly any normal data protocol
including TCP/IP.

BACnet protocol enables the comprehensive BMSs (building management

systems) development that allows operators to construct, observe & control
different building systems within a single application.
This protocol is also used to expand the flexibility & scope of the automation
that can be executed. For instance, an automation system could be setup such
that once the fire protection system notices a fire, then the system sends
commands to the following.

 To the control system of the elevator to send all elevators to the ground
floor immediately.
 To the paging system of the building to transmit an audible voice
signal to inform occupants of the building wherever the blaze was
detected & how to go out from the building.
 From the audio or visual systems of the building to flash messages on
TV displays within the conference rooms.
 To an interface of phone system for sending alerts through text
message to the facilities & engineering teams of the building.

The BACnet object example for a binary input of a sensor within a building is
shown below.

Object Name Space Temp

Type of Object Binary Input
Present Value 11001
Status Flags Normal, InService
High Limit 11110
11011
Low Limit

Different Types

The different types of BACnet protocols are discussed below.

BACnet/IP

This is normally used with existing VLAN & WAN networks. So the devices
can connect directly to hubs or Ethernet switches. This LAN is a high-
performance & fast type, but very costly. BACnet/IP utilizes UDP/IP for
compatibility through existing IP infrastructure. Once BACnet/IP is utilized
with several IP subnets, then extra device functionality known as BBMDs
(BACnet Broadcast Management Devices) is necessary to handle broadcast
messages of inter-subnet BACnet.
BACnet MS/TP

This kind of LAN uses EIA-485 twisted pair for signaling up to 4k feet. So it is
a very famous type of BACnet LAN which is used for unitary as well as
application-specific controllers. This BACnet MS/TP is not expensive.

BACnet ISO 8802-3 (Ethernet)

BACnet is directly used with Ethernet 8802-3 networks which are similar to
BACnet/IP in terms of speed & cost, although restricted to a single physical
infrastructure that does not utilize IP routers.
BACnet over ARCNET

This BACnet is MAC type which includes two forms like 2.5Mbs coax &
156Kbs above EIA-485. This BACnet is supported by a limited number of
vendors with ARCNET.

BACnet Point-to-Point

This BACnet Point-to-Point is simply used over the networks of dial-up

telephones. Generally, thus direct EIA-232 connection is no longer used for a
direct Ethernet connection.

BACnet over LonTalk Foreign Frames

This BACnet simply allows LonTalk’s transport component for carrying

BACnet messages. But, the two protocols are not interoperable.

BACnet over ZigBee

Generally, this MAC is a wireless mesh network used with less costly devices.
So it is normally used as a gateway to ZigBee devices & not like a native
BACnet transport.

Bacnet to Modbus Converter

Protocon-P3 Gateway is a BACnet to Modbus converter which is used in

designing automation systems in different applications like HVAC, access
control, lighting control & fire detection systems, and their related equipment.
The Protocon-P3 Gateway combines such BACnet systems & devices with
Modbusbased management systems over Modbus RTU protocol & Modbus
TCP/IP.
The main features of Bacnet to Modbus Converter include the following.

 It includes a front panel that has LED for indication of quick

diagnostic
 Windows-based configuration utility.
 It supports up to 100 BACnet devices interface to TCP Master/Slave or
Modbus RTU.
 It has the capacity for interfacing up to 5K mapping points.
 It supports the COV bit packing feature.

Applications

The use of Bacnet Protocol includes the following.

 The BACnet is used in HVAC applications, fire control lighting
control, security, alarm & interfacing to utility companies.
 This protocol was particularly designed for building automation as
well as control applications.
 This protocol is used to provide mechanisms, especially for automation
devices for exchanging data irrespective of the specific building
service they perform.
 This protocol can be used by digital controllers, computers &
application-specific otherwise unitary controllers with equivalent
effect.
 BACnet protocol was initially developed to develop interoperability
between building automation devices; however, its data descriptions,
as well as flexible architecture, will make it work within a broad range
of control applications.

Advantages

The advantages of the Bacnet Protocol include the following.

  BACnet protocol is particularly designed for building automation as
well as control networks.
 It doesn’t depend on present LAN or WAN technologies.
 It is an American National Standard & a European pre-standard.
 It is scalable completely from small single building applications to
universal networks of devices.
 The implementers of BACnet can securely include non-standard
extensions as well as enhancements without influencing existing
interoperability.
 It is adopted by the most famous fire protection companies in both the
USA & Europe.
 It is supported by different chiller manufacturers like Dunham-Bush,
Carrier, McQuay, York & Trane.
 In real building control applications, this protocol has a proven track
record.
Disadvantages

The disadvantages of the Bacnet Protocol include the following.

The main drawback of the BACnet protocol was a compliant problem. So
because of this issue, the BTL (BACnet Testing Laboratories) was introduced in
the year 2000. BTL is compliance & and independent testing organization. The
main intention of this is to test the products of BACnet to verify compliance
with the standard. Once approved; the product will get the logo of BTL.

MODBUS

Modbus is a request-response protocol implemented using a master-slave

relationship. In a master-slave relationship, communication always occurs in
pairs—one device must initiate a request and then wait for a response—and the
initiating device (the master) is responsible for initiating every interaction.
Typically, the master is a human machine interface (HMI) or Supervisory
Control and Data Acquisition (SCADA) system and the slave is a sensor,
programmable logic controller (PLC), or programmable automation controller
(PAC). The content of these requests and responses, and the network layers
across which these messages are sent, are defined by the different layers of the
protocol.
Layers of the Modbus Protocol

In the initial implementation, Modbus was a single protocol built on top of

serial, so it could not be divided into multiple layers. Over time, different
application data units were introduced to either change the packet format used
over serial or to allow the use of TCP/IP and user datagram protocol (UDP)
networks. This led to a separation of the core protocol, which defines the
protocol data unit (PDU), and the network layer, which defines the application
data unit (ADU).

Protocol Data Unit

The PDU and the code that handles it comprise the core of the Modbus
Application Protocol Specification. This specification defines the format of the
PDU, the various data concepts used by the protocol, the use of function codes
to access that data, and the specific implementation and restrictions of each
function code.

The Modbus PDU format is defined as a function code followed by an

associated set of data. The size and contents of this data are defined by the
function code, and the entire PDU (function code and data) cannot exceed 253
bytes in size. Every function code has a specific behavior that slaves can
flexibly implement based on their desired application behavior. The PDU
specification defines core concepts for data access and manipulation; however,
a slave may handle data in a way that is not explicitly defined in the
specification.

Accessing Data in Modbus and the Modbus Data Model

Modbus-accessible data is stored, in general, in one of four data banks or
address ranges: coils, discrete inputs, holding registers, and input registers. As
with much of the specification, the names may vary depending on the industry
or application. For example, holding registers may be referred to as output
registers, and coils may be referred to as digital or discrete outputs. These data
banks define the type and access rights of the contained data. Slave devices
have direct access to this data, which is hosted locally on the devices. The
Modbus-accessible data is generally a subset of the device’s main memory. In
contrast, Modbus masters must request access to this data through various
function codes.

Master
Memory Block Data Type Slave Access
Access

Coils Boolean Read/Write Read/Write

Discrete
Boolean Read-only Read/Write
Inputs

Holding
Unsigned Word Read/Write Read/Write
Registers

Input
Unsigned Word Read-only Read/Write
Registers

These blocks give you the ability to restrict or permit access to different data
elements and also to provide simplified mechanisms at the application layer to
access different data types.

The blocks are completely conceptual. They may exist as separate memory
addresses in a given system, but they may also overlap. For example, coil one
may exist in the same location in memory as the first bit of the word represented
by holding register one. The addressing scheme is entirely defined by the slave
device, and its interpretation of each memory block is an important part of the
device’s data model.

Data Model Addressing

The specification defines each block as containing an address space of as many
as 65,536 (216) elements. Within the definition of the PDU, Modbus defines the
address of each data element as ranging from 0 to 65,535. However, each data
element is numbered from 1 to n, where n has a maximum value of 65,536. That
is, coil 1 is in the coil block at address 0, while holding register 54 is at address
53 in the section of memory that the slave has defined as holding registers.
Data Addressing Ranges
Although the specification defines different data types as existing in different
blocks and assigns a local address range to each type, this does not necessarily
translate into an intuitive addressing scheme for the purposes of documentation
or understanding a given device’s Modbus-accessible memory. To simplify the
discussion of memory block locations, a numbering scheme was introduced,
which added prefixes to the address of the data in question.

For example, rather than referring to an item as holding register 14 at address

13, a device manual would refer to a data item at address 4,014, 40,014, or
400,014. In each case, the first number specified is 4 to represent holding
registers, and the address is specified using the remaining numbers. The
difference between 4XXX, 4XXXX, and 4XXXXX depends on the address
space used by the device. If all 65,536 registers are in use, 4XXXXX notation
should be used, as it allows for a range from 400,001 to 465,536. If only a few
registers are used, a common practice is to use the range 4,001 through 4,999.

Data Block Prefix

Coils 0

Discrete Inputs 1

Input Registers 3

Holding Registers 4

Data Address Start Values

The difference between memory addresses and reference numbers is further
complicated by the indexing selected by a given application. As mentioned
previously, holding register one is at address zero. Typically, reference numbers
are one-indexed, meaning that the start value of a given range is one. Thus,
400,001 translates literally to holding register 00001, which is at address 0.
Some implementations choose to start their ranges at zero, meaning that
400,000 translates to the holding register at address zero. Table 3 demonstrates
this concept.

Address Register Number (1- Number (0-

 indexing, indexing,
Number
standard) alternative)

0 1 400001 400000

1 2 400002 400001

2 3 400003 400002

Large Data Types

The Modbus standard supplies a relatively simplistic data model that does not
include additional data types outside of an unsigned word and bit value.
Although this is sufficient for some systems, where the bit values correspond to
solenoids and relays and the word values correspond to unscaled ADC values, it
is insufficient for more advanced systems. As a result, many Modbus
implementations include data types that cross register boundaries. The
NI LabVIEW Datalogging and Supervisory Control (DSC)
Module and KEPServerEX both define a number of reference types. For
example, strings stored in a holding register follow the standard form (400,001)
but are followed by a decimal, the length, and the byte ordering of the string
(400,001.2H, a two character string in holding register 1 where the high byte
corresponds to the first character of the string). This is required because each
request has finite size, and so a Modbus master must know the exact bounds of
the string rather than searching for a length or delimiter like NULL.

Bit Access
In addition to allowing access to data that crosses a register boundary, some
Modbus masters support references to individual bits within a register. This is
beneficial as is allows devices to combine data of every type in the same
memory range without having to split binary data into the coil and discrete input
ranges. This is usually referenced using a decimal point and the bit index or
number, depending on the implementation. That is, the first bit in the first
register may be 400,001.00 or 400,001.01. It is recommended that any
documentation specify the indexing scheme used.

Large Data Types

The Modbus standard supplies a relatively simplistic data model that does not
include additional data types outside of an unsigned word and bit value.
Although this is sufficient for some systems, where the bit values correspond to
solenoids and relays and the word values correspond to unscaled ADC values, it
is insufficient for more advanced systems. As a result, many Modbus
implementations include data types that cross register boundaries. The
NI LabVIEW Datalogging and Supervisory Control (DSC)
Module and KEPServerEX both define a number of reference types. For
example, strings stored in a holding register follow the standard form (400,001)
but are followed by a decimal, the length, and the byte ordering of the string
(400,001.2H, a two character string in holding register 1 where the high byte
corresponds to the first character of the string). This is required because each
request has finite size, and so a Modbus master must know the exact bounds of
the string rather than searching for a length or delimiter like NULL.

Bit Access
In addition to allowing access to data that crosses a register boundary, some
Modbus masters support references to individual bits within a register. This is
beneficial as is allows devices to combine data of every type in the same
memory range without having to split binary data into the coil and discrete input
ranges. This is usually referenced using a decimal point and the bit index or
number, depending on the implementation. That is, the first bit in the first
register may be 400,001.00 or 400,001.01. It is recommended that any
documentation specify the indexing scheme used.

Strings
Strings can be easily stored in Modbus registers. For simplicity, some
implementations require that string lengths be multiples of two, with any
additional space filled with null values. Byte order is also a variable in string
interactions. String format may or may not include a NULL as the final value.
As an example of this variability, some devices may store data
The Modbus PDU
The PDU consists of a one-byte function code followed by up to 252 bytes of
function-specific data.

ZIGBEE ARCHITECTURE

ZigBee is a Personal Area Network task group with low rate task group 4. It is
a technology of home networking. ZigBee is a technological standard created
for controlling and sensing the network. As we know that ZigBee is the
Personal Area Network of task group 4 so it is based on IEEE 802.15.4 and is
created by Zigbee Alliance.

ZigBee is an open, global, packet-based protocol designed to provide an

easy-to-use architecture for secure, reliable, low power wireless networks.
Flow or process control equipment can be place anywhere and still
communicate with the rest of the system. It can also be moved, since the
network doesn’t care about the physical location of a sensor, pump or valve.
ZigBee is a standard that addresses the need for very low-cost implementation
of Low power devices with Low data rates for short-range wireless
communications.

IEEE 802.15.4 supports star and peer-to-peer topologies. The ZigBee

specification supports star and two kinds of peer-to-peer topologies, mesh and
cluster tree. ZigBee-compliant devices are sometimes specified as supporting
point-to-point and point-to-multipoint topologies.
Why another short-range communication standard??

Types of ZigBee Devices:

 Zigbee Coordinator Device: It communicates with routers. This

device is used for connecting the devices.
 Zigbee Router: It is used for passing the data between devices.
 Zigbee End Device: It is the device that is going to be controlled.
General Characteristics of Zigbee Standard:

 Low Power Consumption

 Low Data Rate (20- 250 kbps)
 Short-Range (75-100 meters)
 Network Join Time (~ 30 msec)
 Support Small and Large Networks (up to 65000 devices (Theory);
240 devices (Practically))
 Low Cost of Products and Cheap Implementation (Open Source
Protocol)
 Extremely low-duty cycle.
 3 frequency bands with 27 channels.
Operating Frequency Bands (Only one channel will be selected for use in a
network):
1. Channel 0: 868 MHz (Europe)
2. Channel 1-10: 915 MHz (the US and Australia)
3. Channel 11-26: 2.4 GHz (Across the World)

Features of Zigbee:

1. Stochastic addressing: A device is assigned a random address and

announced. Mechanism for address conflict resolution. Parents node don’t
need to maintain assigned address table.
2. Link Management: Each node maintains quality of links to neighbors.
Link quality is used as link cost in routing.

3. Frequency Agility: Nodes experience interference report to channel

manager, which then selects another channel
4. Asymmetric Link: Each node has different transmit power and sensitivity.
Paths may be asymmetric.
5. Power Management: Routers and Coordinators use main power. End
Devices use batteries.

Zigbee Network Topologies:

 Star Topology (ZigBee Smart Energy): Consists of a coordinator

and several end devices, end devices communicate only with the
coordinator.
 Mesh Topology (Self Healing Process): Mesh topology consists of
one coordinator, several routers, and end devices.
 Tree Topology: In this topology, the network consists of a central
node which is a coordinator, several routers, and end devices. the
function of the router is to extend the network coverage.

Architecture of Zigbee:

Zigbee architecture is a combination of 6 layers.

1. Application Layer
2. Application Interface Layer
3. Security Layer
4. Network Layer
5. Medium Access Control Layer
6. Physical Layer
  Physical layer: The lowest two layers i.e the physical and the MAC
(Medium Access Control) Layer are defined by the IEEE 802.15.4
specifications. The Physical layer is closest to the hardware and
directly controls and communicates with the Zigbee radio. The
physical layer translates the data packets in the over-the-air bits for
transmission and vice-versa during the reception.
 Medium Access Control layer (MAC layer): The layer is
responsible for the interface between the physical and network layer.
The MAC layer is also responsible for providing PAN ID and also
network discovery through beacon requests.
 Network layer: This layer acts as an interface between the MAC
layer and the application layer. It is responsible for mesh networking.
 Application layer: The application layer in the Zigbee stack is the
highest protocol layer and it consists of the application support sub-
layer and Zigbee device object. It contains manufacturer-defined
applications.
Channel Access:
1. Contention Based Method (Carrier-Sense Multiple Access With
Collision Avoidance Mechanism)
2. Contention Free Method (Coordinator dedicates a specific time slot
to each device (Guaranteed Time Slot (GTS)))

Zigbee Applications:

1. Home Automation
2. Medical Data Collection
3. Industrial Control Systems
 4. meter reading system
5. light control system
6. Commercial
7. Government Markets Worldwide
8. Home Networking

Advantages of Zigbee:
1. Designed for low power consumption.
2. Provides network security and application support services operating
on the top of IEEE.
3. Zigbee makes possible completely networks homes where all devices
are able to communicate and be
4. Use in smart home
5. Easy implementation
6. Adequate security features.
7. Low cost: Zigbee chips and modules are relatively inexpensive,
which makes it a cost-effective solution for IoT applications.
8. Mesh networking: Zigbee uses a mesh network topology, which
allows for devices to communicate with each other without the need
for a central hub or router. This makes it ideal for use in smart home
applications where devices need to communicate with each other and
with a central control hub.
9. Reliability: Zigbee protocol is designed to be highly reliable, with
robust mechanisms in place to ensure that data is delivered reliably
even in adverse conditions.
Disadvantages of Zigbee :
1. Limited range: Zigbee has a relatively short range compared to
other wireless communications protocols, which can make it less
suitable for certain types of applications or for use in large buildings.
2. Limited data rate: Zigbee is designed for low-data-rate
applications, which can make it less suitable for applications that
require high-speed data transfer.
3. Interoperability: Zigbee is not as widely adopted as other IoT
protocols, which can make it difficult to find devices that are
compatible with each other.
4. Security: Zigbee’s security features are not as robust as other IoT
protocols, making it more vulnerable to hacking and other security
threats.

NETWORK LAYER
The network layer works for the transmission of data from one host to the
other located in different networks. It also takes care of packet routing i.e.
selection of the shortest path to transmit the packet, from the number of routes
available. The sender & receiver’s IP addresses are placed in the header by the
network layer.
The Network Layer is the 5th Layer from the top and the 3rd layer from
the Bottom of the OSI Model. It is one of the most important layers which
plays a key role in data transmission. The main job of this layer is to
maintain the quality of the data and pass and transmit it from its source
to its destination. It also handles routing, which means that it chooses the
best path to transmit the data from the source to its destination, not just
transmitting the packet. There are several important protocols that work
in this layer.

Data is transmitted in the form of packets via various logical network

pathways between various devices. In the seven-layer open system
interconnection paradigm, the network layer is the third layer. It offers
routes for data packet transfers across the network. The network layer is
also responsible for organising and controlling the available paths for
data transfer.

Functions of Network Layer

Network Layer serves various important functions in the data transport
mechanism. It is also responsible for the routing mechanism in which it selects
the best path to transfer the data from source to it’s destination. It divides the
entire data into smaller packets which eases the transfer procedure. It is also
responsible for attaching the logical address to the devices between which the
data transmission is happening, so that the packets reach correct destination
and the destination can confirm that it is the same packet it was looking for.
Some of the most important functions of the network layer is given below.

1. Assigning Logical Address

Network layer is solely responsible for assigning logical addresses to devices
which are either sending or receiving data packets. It is useful to uniquely
identify each devices in a certain network. The data packets sent or received
consists the IP address of both the sender device and the receiver device. It is
useful to confirm that the packets are sent or received by the desired parties.
There are two part in an IP address, a Host ID and Network ID, using the Host
ID it can be confirmed that the packets were sent by the authorized sender and
it has successfully reached the desired receiver.
2. Routing
Routing is the process of identifying the best path to transmit the packets,
Network Layer not only just sends packets from sender to receiver, but also
determines the best route to send them. Numerous routers are used to find out
the best and safest route to transmit the data packets. Various routing
algorithms are used to determine the best path, like link state routing, Distance
Vector Routing, Flooding, Random Walk etc. The header of each data packet
holds the information regarding the path they need to follow to reach their
destination via different routers. Usually there are multiple routers between the
sender and the receiver, so the data packets are routed by using all these
available routers.
3. Host-to-Host delivery
Host-to-Host delivery also known as Forwarding is the process in which the
network layer transmits or forwards the data packets via routers, after
determining the best path/route. In some cases it takes more than one router to
reach the destination, Network Layer takes care of those too, it forwards
packets from each router to the another router until it reaches the destination
securely.
4. Logical Subnetting
Network Layer also allows a bigger network to be divided into smaller chunks
of network known as Logical Subnetting. It helps the IP addresses to be used
more efficiently and less amount of IP address will be wasted. It is also helpful
to manage a larger network more efficiently. Due to smaller networks, it
would be easier to find the device if any troubleshooting is needed.
5. Fragmentation and Reassembly
Each device / node has a maximum capacity to receive data (it may differ from
Node to Node), which is called Maximum Transmission Unit (MTU). If the
total size of data packets exceedes that size limit, then those data packets are
fragmented into more smaller packets / fragmented so that they can fit the
MTU. After fragmentation those packets are being send to the receiver, and at
the receiving end all those fragmented packets are rearranged to create the
actual data in order. The fragmentation is taken care by the routers.
6. Error Handling
Network Layer also check for errors and handles them. Network Layer uses
various error detection techniques like Cylic Redundancy Check (CRC) ,
Checksums etc. Apart from just detecting, it also handle those errors using
different approaches like Forward Error Correction (FEC), Hamming
Code, Reed-Solomon Codes etc. It also re-transmit the packets which are
either erroneous or didn’t reach the receiver. It uses the ACK messages to
determine whether a packet has been successfully reached the receiver or not,
if there is a Negative ACK, then it means that there is some error with the
packet, and the receiver will ask the sender to resend that packet.
7. Quality of Service (QoS)
Network layer also keep track of the important data or the particular quality of
data which is needed to be send first. Based on the QoS settings, it determines
and prioritize the important data types which needed to be send first. It ensures
that there is no delay in receiving the important data in any condition.
8. Network Address Translation (NAT)
Network Layer also takes care of the Network Address Translation (NAT),
means that it converts any private IP address into a public IP address which is
required to communicate between the sender and the receiver.
9. Congestion Control
Just like MTU, if there is an excessive load on the network which it can’t
handle, the network become congested. Due to which the entire process of
sending and receiving data comes to a pause. Congestion can be dealt with
using different algorithms like Leaky Bucket Algorithm and Token Bucket
Algorithm. In case of the leaky bucket algorithm, whatever might be the speed
or amount of data flow into the bucket, the data leaks at a constant rate, which
reduces the congestion in the network. In case of the Token Bucket Algorithm,
tokens are being added into the bucket one by one, until it has reached the
maximum capacity, then one by one according the token sequence each data
packet is transmitted.
10. Encapsulation and Decapsulation
Network Layer encapsulates the data coming from the Transport Layer, and
also adds important header parts to the packets, which consists of the
necessary information like source IP address and destination IP address. After
receiving the data packets on the destination side it decapsulates those and
make them of original size.
Working of Network Layer
The network layer will initially receive data from the OSI model’s transport
layer as part of the data flow between that layer and other OSI levels. These
data packets are handled by the network layer by include their source and
destination addresses. Additionally, it incorporates the network protocols for
proper transfer to the data-link layer over the network channel.
Responsibilities of the Network Layer
In the network channel and communication channel, the network layer is in
charge of the responsibilities listed below:
 It is in charge of managing the network channel’s quickest routing
path for the data packet.
 The network layer packages the data that has been received for
transmission.
 maintains the network traffic in the channel by handling the network
layer protocols.
Protocols Used at Network Layer
A protocol is a set of rules for data structuring that enables communication and
mutual understanding between two or more devices. At the network layer, a
variety of protocols enable connections, testing, routing, and encryption,
including:
 IP
 IPsec
 ICMP
 IGMP
 GRE
Problems with the Network layer design
  The decision of how to direct packets is a pivotal aspect of network
layer design. It holds great significance as it sets the groundwork for
the protocol governing the transmission of packets between nodes in
a network.
 In the nodes, data transmission can be facilitated through either static
tables or dynamic tables. These tables serve as the routes for the
transmission of information. The paths may be pre-established or
subject to frequent alteration.
 The smooth flow of data in the network can be disrupted
unexpectedly if there is an overwhelming abundance of packets
being transmitted or present on the network. Consequently, the
network might encounter bottlenecks causing a decline in its
performance.
 Separate protocols are needed to enable communication between the
two networks.
Advantages of Network Layer
 Using the network layer in the OSI paradigm offers a multitude of
advantages. Let’s delve into some of these benefits:
 The network layer takes the data and breaks it down into packets,
which makes transmitting the data over the network easier. This
process also eliminates any weak points in the transmission, ensuring
that the packet successfully reaches its intended destination.
 Router is the important component of the network layer . Its role is to
reduce network congestion by facilitating collisions and broadcasting
the domains within the network layer.
 Used to send data packets across the network nodes, the forwarding
method is various.
Disadvantages of Network Layer
 There is no flow control mechanism provided by the network layer
design.
 There may be times when there are too many datagrams in transit
over the network, causing congestion. This could put further strain on
the network routers. In some circumstances, the router may lose
some data packets if there are too many datagrams. Important data
may be lost in the process of transmission as a result of this.
 Indirect control cannot be implemented at the network layer since the
data packets are broken up before being sent. Additionally, this layer
lacks effective error control systems.

6LOWPAN
6LoWPAN is an IPv6 protocol, and It’s extended from is IPv6 over Low
Power Personal Area Network. As the name itself explains the meaning of this
protocol is that this protocol works on Wireless Personal Area Network i.e.,
WPAN.
WPAN is a Personal Area Network (PAN) where the interconnected devices
are centered around a person’s workspace and connected through a wireless
medium. You can read more about WPAN at WPAN. 6LoWPAN allows
communication using the IPv6 protocol. IPv6 is Internet Protocol Version 6 is
a network layer protocol that allows communication to take place over the
network. It is faster and more reliable and provides a large number of
addresses.
6LoWPAN initially came into existence to overcome the conventional
methodologies that were adapted to transmit information. But still, it is not so
efficient as it only allows for the smaller devices with very limited processing
ability to establish communication using one of the Internet Protocols, i.e.,
IPv6. It has very low cost, short-range, low memory usage, and low bit rate.
It comprises an Edge Router and Sensor Nodes. Even the smallest of the IoT
devices can now be part of the network, and the information can be transmitted
to the outside world as well. For example, LED Streetlights.


It is a technology that makes the individual nodes IP enabled.
 6LoWPAN can interact with 802.15.4 devices and also other types
of devices on an IP Network. For example, Wi-Fi.
 It uses AES 128 link layer security, which AES is a block cipher
having key size of 128/192/256 bits and encrypts data in blocks of
128 bits each. This is defined in IEEE 802.15.4 and provides link
authentication and encryption.
Basic Requirements of 6LoWPAN:
1. The device should be having sleep mode in order to support the
battery saving.
2. Minimal memory requirement.
3. Routing overhead should be lowered.
Features of 6LoWPAN:
1. It is used with IEEE 802.15,.4 in the 2.4 GHz band.
2. Outdoor range: ~200 m (maximum)
3. Data rate: 200kbps (maximum)
4. Maximum number of nodes: ~100
Advantages of 6LoWPAN:
1. 6LoWPAN is a mesh network that is robust, scalable, and can heal
on its own.
2. It delivers low-cost and secure communication in IoT devices.
3. It uses IPv6 protocol and so it can be directly routed to cloud
platforms.
4. It offers one-to-many and many-to-one routing.
5. In the network, leaf nodes can be in sleep mode for a longer duration
of time.
Disadvantages of 6LoWPAN:
1. It is comparatively less secure than Zigbee.
2. It has lesser immunity to interference than that Wi-Fi and Bluetooth.
3. Without the mesh topology, it supports a short range.
Applications of 6LoWPAN:
1. It is a wireless sensor network.
2. It is used in home-automation,
3. It is used in smart agricultural techniques, and industrial monitoring.
4. It is utilised to make IPv6 packet transmission on networks with
constrained power and reliability resources possible.
Security and Interoperability with 6LoWPAN:
 Security: 6LoWPAN security is ensured by the AES algorithm,
which is a link layer security, and the transport layer security
mechanisms are included as well.
 Interoperability: 6LoWPAN is able to operate with other wireless
devices as well which makes it interoperable in a network.
The Future of 6LoWPAN
In the IoT sector, 6LoWPAN has the potential to overtake other networking
technologies. It is the best option for integrating the billions of devices that are
anticipated to be a part of the IoT in the upcoming years because of its
efficiency and scalability.

The need for a more effective and scalable networking solution will only
increase as more and more devices are connected. This demand may be met by
6LoWPAN, which offers an IoT industry solution that is future-proof.

CoAP
COAP is a lightweight, RESTful protocol designed specifically for the Internet
of Things. COAP is optimized for low-power devices and networks with limited
resources. The COAP protocol was designed to provide a low-overhead channel
of communication that is ideal for IoT devices’ requirements for low latency,
small packet sizes, and low power consumption.
COAP is based on similar principles as HTTP, but there are also some
significant differences. COAP is intended for usage on low-power, low-
bandwidth, and unstable networks, such as those present in IoT environments,
in contrast to HTTP. With a number of characteristics that support preventing
unauthorized access and ensuring the privacy of communication, COAP is also
intended to be more secure than HTTP.
Features of COAP Protocol

The COAP protocol provides several benefits that make it a desirable choice for
IoT connectivity. These features include:

COAP utilizes URIs (Uniform Resource Identifiers) to identify

resources on a server, providing a standardized and easily-
understood naming convention for resource requests.
 COAP provides the ability to cache messages, reducing the number
of messages transmitted between clients and servers and improving
performance.
 COAP offers support for encryption, providing a secure
communication channel between devices and the internet.
 The ability of COAP to handle asynchronous communication is one
of its fundamental characteristics. This implies that devices don’t
have to wait for a response before sending or receiving data. This is
particularly important in IoT environments, where devices often
have limited resources and may be unable to handle large amounts
of data at once.
 Another key feature of COAP is its support for resource discovery.
This allows devices to discover resources that are available on other
devices, and to determine the type of data that can be requested from
those resources. In IoT environments, resource discovery is crucial
because it enables devices to find and communicate with other
devices even if they are not directly connected.
Advantages of COAP

The COAP protocol offers a number of advantages over other protocols,

particularly in the context of IoT:

Low power consumption: COAP’s low overhead means that it uses less power
than other protocols, making it ideal for battery-powered IoT devices.
Low latency: The COAP protocol is designed to have low latency, providing
fast communication between devices and the internet.
Small packet sizes: COAP’s small packet sizes reduce the amount of data
transmitted between devices and the internet, helping to reduce network
congestion and improve performance.
Easy integration: COAP is designed to be easily integrated into existing IoT
ecosystems, making it simple for developers to add COAP support to their
devices and for existing IoT systems to adopt COAP as their communication
protocol.
Security: COAP provides support for encryption, helping to protect against
security threats such as eavesdropping and tampering.
Use Cases for COAP

The COAP protocol has a number of potential use cases, including:

Smart homes: COAP can be used to provide communication between IoT

devices in a smart home, such as smart thermostats, smart locks, and smart
lighting systems.
Industrial automation: COAP can be used in industrial automation to provide
communication between IoT devices, such as sensors and actuators.

Finally, COAP is designed to be highly scalable. The protocol can be used in

both small and large-scale IoT networks and can support tens of thousands of
devices. This scalability is achieved through the use of a hierarchical structure,
where devices can be organized into groups and resources can be divided
among different devices.

CoAP Messages Model

This is the lowest layer of CoAP. This layer deals with UDP exchanging
messages between endpoints. Each CoAP message has a unique ID; this is
useful to detect message duplicates. A CoAP message is built by these parts:

 A binary header
 A compact options
 Payload

CoAP Architecture
The WWW and the constraints ecosystem are the 2 foundational elements of the
CoAP protocol architecture. Here, the server monitors and helps in
communication happening using CoAP and HTTP while proxy devices bridge
the existing gap for these 2 ecosystem, making the communication smoother.
CoAP allows HTTP clients (also called CoAP clients here) to talk or exchange
data/information with each other within resource constraints.
While one tries to understand this architecture, gaining acquaintances with some
key terms is crucial:

 Endpoints are the nodes that host have knowledge of;

 Client sends requests and replies to incoming requests;
 Server gets and forwards requests. It also gets and forwards the messages
received in response to the requests it had processed.
 Sender creates and sends the original message.
 Recipient gets the information sent by the client or forwarded by the
server.

CoAP Function
The key role of CoAP is to act like HTTP wherever restricted devices are a part
of communication. While filling the gap of HTTP, it enables devices like
actuators and sensors to interact over the internet.
The devices, involved in the process, are administered and controlled by
considering data as a system’s component. CoAP protocol can operate its
functions in an environment having reduced bandwidth and extreme congestion
as it consumes reduced power and network bandwidth.
Networks featuring intense congestion and constrained connectivity are not
ideal conditions for TCP-based protocols to carry out their responsibilities.
CoAP comes as a rescuer at this place and supports the wen transfers.
Web transfers happening using satellites and covering long distances can be
accomplished with full perfection using CoAP. Networks featuring billions of
nodes take the help of the CoAP protocol for information exchange.
Regardless of the function handled or role played, CoAP promised security of
highest grade as DTLS parameters as default security parameter; the counterpart
of 128 bit RSA keys.
Speaking of its deployment, it’s simple and hassle-free. It can be implemented
from scratch for a straightforward application.
For the application ecosystem where CoAP is not desirable, generic
implementations are offered for various platforms. Most of the CoAP
implementations are done privately while few are published in open-source
libraries like MIT license.

CoAP Layer
The protocol works through its two layers:

1. CoAP Messages Model

It makes UDP transactions possible at endpoints in the confirmable (CON) or
non-confirmable (NON) format. Every CoAP message features a distinct ID to
keep the possibilities of message duplications at bay.
The 3 key parts involved to build this layer are binary header, computer option,
and payload.
As explained before, confirmable texts are reliable and easy-to-construct
message that are fast and are resent until the receipt of a confirmation of
successful delivery (ACK) with message ID.

2. CoAp Request/Response Model

This layer takes care of CON and NON message requests. Acceptance of these
requests depend on server’s availability. Cases are:

1. If idle, the server will handle the request right away. If a CON, the client
will get an ACK for it. If the ACK is shared as a Token and differs from
the ID, it is essential to map it properly by matching request-response
pairs.
 2. If there is a delay or wait involved, the ACK is sent but as an empty text.
When its turn arrvies, the request is processed andthe client gets a fresh
CON.
The key traits of the Request/Response model are mentioned next:

 Request or response codes for CoAP are same as for the HTTP, except
for the fact that they are in the binary format (0-8 byte Tokens) in CoAP’s
case.
 Request methods for making calls (GET, PUT, POST, and DELETE) are
declared in the process.
 A CON response could either be stored in an ACK message or forward as
CON/NON.