The document discusses various protocols used in Internet of Things (IoT). It begins with defining IoT and how it works. It then discusses the current status and future of IoT. The major sections of the document are on IoT data link protocols like IEEE 802.15.4, WirelessHART, Z-Wave, and Bluetooth Low Energy. It also covers network layer routing protocols such as RPL and CORPL, and network layer encapsulation protocols.
High level overview of CoAP or Constrained Application Protocol. CoAP is a HTTP like protocol suitable for constrained environment like IoT. CoAP uses HTTP like request response model, status code etc.
The slides defines IoT and show the differnce between M2M and IoT vision. It then describes the different layers that depicts the functional architecture of IoT, standard organizations and bodies and other IoT technology alliances, low power IoT protocols, IoT Platform components, and finally gives a short description to one of IoT low power application protocols (MQTT).
The Internet of Things (IoT), sometimes referred to as the Internet of Objects, IoT is basically a complex network that seamlessly connects people and things together through the Internet. Theoretically, anything that can be connected (smart watches, cars, homes, thermostats, vending machines, servers…) and will be connected in the near future using sensors and RFID tags. This allows connected objects to continuously send data over the Web and from anywhere. The first time the term was used in 1999 by Kevin Ashton, the creator of the RFID standard.
High level overview of CoAP or Constrained Application Protocol. CoAP is a HTTP like protocol suitable for constrained environment like IoT. CoAP uses HTTP like request response model, status code etc.
The slides defines IoT and show the differnce between M2M and IoT vision. It then describes the different layers that depicts the functional architecture of IoT, standard organizations and bodies and other IoT technology alliances, low power IoT protocols, IoT Platform components, and finally gives a short description to one of IoT low power application protocols (MQTT).
The Internet of Things (IoT), sometimes referred to as the Internet of Objects, IoT is basically a complex network that seamlessly connects people and things together through the Internet. Theoretically, anything that can be connected (smart watches, cars, homes, thermostats, vending machines, servers…) and will be connected in the near future using sensors and RFID tags. This allows connected objects to continuously send data over the Web and from anywhere. The first time the term was used in 1999 by Kevin Ashton, the creator of the RFID standard.
This is a technical presentation describing two protocols namely MQTT and CoAP for IoT communications. This explains the protocols in conjunction with OSI layers.
constrained application protocol(CoAP) is a specialized web transfer protocol for use with constrained networks in internet of things and constrained devices such as microcontrollers.
The Role of the Communication Protocols in the IoT: Pitfalls and AdvantagesFabio Gatti
IoT solutions should rely on solid basis in order to provide a step for the future. One of the foundation of building IoT solutions is identifying the appropriate communication protocol to use. Choosing among the different communication protocols may be a challenging task due to the fact that some protocols may be the right fit for one scenario but not necessarily for all.
In this session, we will examine the communication protocols including their pitfalls an advantages and how to choose the right one for your solution.
This is a technical presentation describing two protocols namely MQTT and CoAP for IoT communications. This explains the protocols in conjunction with OSI layers.
constrained application protocol(CoAP) is a specialized web transfer protocol for use with constrained networks in internet of things and constrained devices such as microcontrollers.
The Role of the Communication Protocols in the IoT: Pitfalls and AdvantagesFabio Gatti
IoT solutions should rely on solid basis in order to provide a step for the future. One of the foundation of building IoT solutions is identifying the appropriate communication protocol to use. Choosing among the different communication protocols may be a challenging task due to the fact that some protocols may be the right fit for one scenario but not necessarily for all.
In this session, we will examine the communication protocols including their pitfalls an advantages and how to choose the right one for your solution.
Zach Shelby, Chief Nerd and co-founder of Sensinode, gives a high-level tutorial of the new OMA Lightweight M2M standard for Device Management, Network Mangement and Application Data for the Internet of Things. This new CoAP and DTLS based standard provides a complete system interface solution for M2M devices and services.
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Protocol layers are a hierarchical model of network or communication functions. The divisions of the hierarchy are referred to as layers or levels, with each layer performing a specific task. In addition, each protocol layer obtains services from the protocol layer below it and performs services for the protocol layer above it. The Bluetooth system divides communication functions into protocol layers.
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Lot of book tells about what is programming. Many also tell how to write a program, but very few cover the critical aspect of translating logic into a program. Specifically, in this fast paced industry, when you don't have time to think to program, this course comes really handy. It builds on the basics of programming, smooth sailing through the advanced nitty-gritty’s of the Advanced C language by translating logic to code
The Internet of Things (IoT): A Comprehensive Overview
Introduction:
The Internet of Things (IoT) is a revolutionary concept that has transformed the way we interact with the world around us. It refers to the network of physical devices, vehicles, appliances, and other objects embedded with sensors, software, and connectivity capabilities to exchange data and communicate with each other through the internet. This comprehensive overview will delve into the various aspects of IoT, including its definition, key components, applications, challenges, and future prospects.
Definition and Key Components of IoT:
The IoT encompasses a vast ecosystem of interconnected devices that work together to collect and exchange data. Key components of IoT include:
Devices and Sensors: IoT devices are physical objects embedded with sensors, actuators, and connectivity modules that enable them to gather and transmit data. These devices can range from simple sensors like temperature or motion sensors to complex devices like smart appliances, wearables, and industrial machinery.
Connectivity: IoT devices rely on various communication protocols and technologies to connect and exchange data. These include Wi-Fi, Bluetooth, Zigbee, NFC, cellular networks, and more recently, low-power wide-area networks (LPWAN) like LoRaWAN and NB-IoT.
Cloud Computing: IoT devices generate enormous amounts of data, which are typically processed and stored in the cloud. Cloud computing provides the infrastructure and services required to process and analyze this data, enabling real-time insights and remote management of IoT devices.
Data Analytics and Artificial Intelligence (AI): IoT generates massive volumes of data, often referred to as big data. Data analytics and AI techniques are employed to derive valuable insights from this data, enabling predictive analysis, anomaly detection, and optimization of IoT systems.
Applications of IoT:
Smart Homes and Buildings: IoT enables the creation of smart homes and buildings where devices like thermostats, lighting systems, security cameras, and appliances can be interconnected and controlled remotely. This allows for energy optimization, enhanced security, and increased convenience.
Industrial Internet of Things (IIoT): IIoT refers to the integration of IoT technologies in industrial settings. It enables real-time monitoring, predictive maintenance, and optimization of industrial processes, leading to increased efficiency, reduced downtime, and cost savings.
Healthcare: IoT has transformative applications in healthcare, including remote patient monitoring, wearable devices for health tracking, smart medical devices, and real-time health data analysis. These advancements enhance patient care, enable early detection of diseases, and improve overall healthcare outcomes.
Smart Cities: IoT can be utilized to create smart cities by integrating various systems such as transportation, infrastructure, energy management, waste management, and p
Internet Of Things(IoT) is emerging technology in future world.The term IoT comprises of Cloud computing, Data mining,
Big data analytics, hardware board. The Security and Interoperability is a main factor that influences the IoT Enegy
consumption is also main fator for IoT application designing.The various protocols such as MQTT,AMQP,XMPP are used in
IoT.This paper analysis the various protocols used in Internet of Things.
Data Communication in Internet of Things: Vision, Challenges and Future Direc...TELKOMNIKA JOURNAL
Ubiquitous technologies based heterogeneous networks has opened a new paradigm of technologies, which are enabled with various different objects called Internet of things (IoT). This field opens new door for innovative and advance patterns with considerable potential advantages in the shape of plethora of monitoring and infotainment applications around us. Data communication is one of the significant area of research in IoT due to its diverse network topologies, where diverse gadgets and devices have integrated and connected with each other. In order to communicate among devices and users, routing should be relible, secure and efficient. Due to diverse and hetrogenous netwok environment, the most of the existing routing solutions do not provide all quality of services requirement in the network. In this paper, we discuss the existing routing trend in IoT, vision and current challenges. This paper also elaborates the technologies and domains to drive this field for future perspectives. The paper concludes with discussion and main points for new researchers in terms of routing to understand about current situation in IoT.
IOT and its communication models and protocols.pdfMD.ANISUR RAHMAN
A brief visual description of the Internet of Things and how it works. Then, we will learn about the communication models of IoT and how their structure defines them. Then we will go for the IoT protocols and know about different types of protocols. At last, we will see some applications of IoT.
Introduction to IoT
Defining IoT,
Characteristics of IoT,
Physical design of IoT,
Logical design of IoT,
Functional blocks of IoT,
Brief review of applications of IoT.
Smart Object
Definition,
Characteristics and Trends
Text Book
1. Arsheep Bahga (Author), Vijay Madisetti, Internet Of Things: A Hands-On Approach
Paperback, Universities Press,
Reprint 2020
2. David Hanes, Gonzalo Salgueiro, Patrick Grossetete, Robert Barton, Jerome Henry,
IoT Fundamentals Networking Technologies, Protocols, and Use Cases for the Internet of
Things CISCO.
Internet of Things.
CSDLO5013
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He discussed the concept of quality improvement, emphasizing its applicability to various aspects of life, including personal, project, and program improvements. He defined quality as doing the right thing at the right time in the right way to achieve the best possible results and discussed the concept of the "gap" between what we know and what we do, and how this gap represents the areas we need to improve. He explained the scientific approach to quality improvement, which involves systematic performance analysis, testing and learning, and implementing change ideas. He also highlighted the importance of client focus and a team approach to quality improvement.
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
2. Topics in this Presentation
What is Internet of Things?
How IoT Works?
Current Status & Future Prospect of IoT
The Future of IoT
IoT Data Link Protocol
Network Layer Routing Protocols
Network Layer Encapsulation Protocols
Session Layer Protocols
2
3. What is IoT?
The Internet of Things (IoT) is the network of physical objects or
"things" embedded with electronics, software, sensors, and network
connectivity, which enables these objects to collect and exchange data.
IoT allows objects to be sensed and controlled remotely across
existing network infrastructure, creating opportunities for more direct
integration between the physical world and computer-based systems,
and resulting in improved efficiency, accuracy and economic benefit.
3
4. "Things," in the IoT sense, can refer to a wide variety
of devices such as heart monitoring implants, biochip
transponders on farm animals, electric clams in coastal
waters, automobiles with built-in sensors, DNA analysis
devices for environmental/food/pathogen monitoring or
field operation devices that assist fire-fighters in search
and rescue operations.
These devices collect useful data with the help of
various existing technologies and then autonomously flow
the data between other devices.
4
5. The concept of the Internet of Things first became
popular in 1999, through the Auto-ID Center at MIT and
related market-analysis publications. R
Radio-frequency identification (RFID) was seen as a
prerequisite for the IoT at that point. If all objects and
people in daily life were equipped with identifiers,
computers could manage and inventory them. Besides
using RFID, the tagging of things may be achieved through
such technologies as near field communication, barcodes,
QR codes, bluetooth, and digital watermarking.
History of IoT
5
6. How IoT Works?
Internet of Things is not the result of a single novel technology;
instead, several complementary technical developments provide
capabilities that taken together help to bridge the gap between the virtual
and physical world. These capabilities include:
Communication and cooperation
Addressability
Identification
Sensing
Actuation
Embedded information processing
Localization
User interfaces
6
7. How IoT Works?
7
RFID Sensor Smart Tech Nano Tech
To identify
and track the
data of
things
To collect and
process the
data to detect
the changes in
the physical
status of things
To enhance the
power of the
network by
devolving
processing
capabilities to
different part of
the network.
To make the
smaller and
smaller things
have the ability
to connect and
interact.
8. The Structure of IoT
The IoT can be viewed as a gigantic network consisting of
networks of devices and computers connected through a series
of intermediate technologies where numerous technologies
like RFIDs, wireless connections may act as enablers of this
connectivity.
Tagging Things : Real-time item traceability and addressability
by RFIDs.
Feeling Things : Sensors act as primary devices to collect data
from the environment.
Shrinking Things : Miniaturization and Nanotechnology has
provoked the ability of smaller things to interact and connect
within the “things” or “smart devices.”
Thinking Things : Embedded intelligence in devices through
sensors has formed the network connection to the Internet. It
can make the “things” realizing the intelligent control.
8
9. Current Status & Future Prospect of IoT
9
“Change is the only thing permanent in this world”
10. Different IOT Protocols
• IoT Data Link Protocol
• Network Layer Routing Protocols
• Network Layer Encapsulation Protocols
• Session Layer Protocols
11. IoT Data Link Protocol
• In this section, we discuss the datalink layer protocol standards. The
discussion includes physical (PHY) and MAC layer protocols which are
combined by most standards.
12. IEEE 802.15.4
• IEEE 802.15.4 is the most commonly used IoT standard for MAC. It
defines a frame format, headers including source and destination
addresses, and how nodes can communicate with each other. The
frame formats used in traditional networks are not suitable for low
power multi-hopnetworking in IoT due to their overhead. In 2008,
IEEE802.15.4e was created to extend IEEE802.15.4 and support low
power communication. It uses time synchronization and channel
hopping to enable high reliability, low cost and meet IoT
communications requirements. Its specific MAC features can be
summarized as follows [802.15.4]:
13. Specific MAC features can be summarized as follows
[802.15.4]:
• Scheduling: The standard does not define how the scheduling is done but it needs to be
built carefully such that it handles mobility scenarios. It can be centralized by a manager
node which is responsible for building the schedule, informing others about the schedule
and other nodes will just follow the schedule
• Synchronization: Synchronization is necessary to maintain nodes’ connectivity to their
neighbors and to the gateways. Two approaches can be used: acknowledgment-based or
frame-based synchronization. In acknowledgement-based mode, the nodes are already
in communication and they send acknowledgment for reliability guarantees, thus can be
used to maintain connectivity as well. In frame-based mode, nodes are not
communicating and hence, they send an empty frame at pre-specified intervals (about
30second typically).
14. WirelessHART
• WirelessHART is a datalink protocol that operates on the top of IEEE 802.15.4
PHY and adoptsvTime Division Multiple Access (TDMA) in its MAC. It is a
secure and reliable MAC protocol that uses advanced encryption to encrypt
the messages and calculate the integrity in order to offer reliability. The
architecture, as shown in Figure 3 consists of a network manager, a security
manager, a gateway to connect the wireless network to the wired networks,
wireless devices as field devices, access points, routers and adapters. The
standard offers end-to-end, per-hop or peer-to- peer security mechanisms.
End to end security mechanisms enforce security from sources to destinations
while per-hop mechanisms secure it to next hop only[Kim08, Raza10].
15.
16. Z-Wave
Z-Wave is a low-power MAC protocol designed for home automation
and has been used for IoT communication, especially for smart home
and small commercial domains. It covers about 30- meter point-to-
point communication and is suitable for small messages in IoT
applications, like light control, energy control, wearable healthcare
control and others. It uses CSMA/CA for collision detection and ACK
messages for reliable transmission. It follows a master/slave
architecture in which the master control the slaves, send them
commands, and handling scheduling of the whole network [Z-Wave].
17. Bluetooth Low Energy
• Bluetooth low energy or Bluetooth smart is a short range communication
protocol with PHY and MAC layer widely used for in-vehicle networking. Its
low energy can reach ten times less than the classic Bluetooth while its
latency can reach 15 times. Its access control uses a contentionless MAC with
low latency and fast transmission. It follows master/slave architecture and
offers two types of frames: adverting and data frames. The Advertising frame
is used for discovery and is sent by slaves on one or more of dedicated
advertisement channels. Master nodes sense advertisement channels to find
slaves and connect them. After connection, the master tells the slave it’s
waking cycle and scheduling sequence. Nodes are usually awake only when
they are communicating and they go to sleep otherwise to save their power
[Decuir10, Gomez12].
18. Network Layer Routing Protocols
• In this section, we discuss some standard and non-standard protocols
that are used for routing in IoT applications. It should be noted that
we have partitioned the network layer in two sublayers:
• routing layer which handles the transfer the packets from source to
destination, and an
• encapsulation layer that forms the packets. Encapsulation
mechanisms will be discussed in the next section.
19. RPL
Routing Protocol for Low-Power and Lossy Networks (RPL) is distance-vector protocol that
can support a variety of datalink protocols, including the ones discussed in the previous
section. It builds a Destination Oriented Directed Acyclic Graph (DODAG) that has only one
route from each leaf node to the root in which all the traffic from the node will be routed to.
At first, each node sends a DODAG Information Object (DIO) advertising itself as the root.
This message is propagated in the network and the whole DODAG is gradually built. When
communicating, the node sends a Destination Advertisement Object (DAO) to its parents,
the DAO is propagated to the root and the root decides where to send it depending on the
destination. When a new node wants to join the network, it sends a DODAG Information
Solicitation (DIS) request to join the network and the root will reply back with a DAO
Acknowledgment (DAO-ACK) confirming the join. RPL nodes can be stateless, which is most
common, or stateful. A stateless node keeps tracks of its parents only. Only root has the
complete knowledge of the entire DODAG. Hence, all communications go through the root
in every case. A stateful node keeps track of its children and parents and hence when
communicating inside a sub-tree of the DODAG, it does not have to go through the root
[RFC6550].
20. CORPL
• An extension of RPL is CORPL, or cognitive RPL, which is designed for cognitive
networks and uses DODAG topology generation but with two new modifications
to RPL. CORPL utilizes opportunistic forwarding to forward the packet by choosing
multiple forwarders (forwarder set) and coordinates between the nodes to
choose the best next hop to forward the packet to. DODAG is built in the same
way as RPL. Each node maintains a forwarding set instead of its parent only and
updates its neighbor with its changes using DIO messages. Based on the updated
information, each node dynamically updates its neighbor priorities in order to
construct the forwarder set [Aijaz15].
21. CARP
• Channel-Aware Routing Protocol (CARP) is a distributed routing protocol designed for
underwater communication. It can be used for IoT due to its lightweight packets. It considers
link quality, which is computed based on historical successful data transmission gathered
fromneighboring sensors, to select the forwarding nodes. There are two scenarios: network
initialization and data forwarding. In network initialization, a HELLO packet is broadcasted from
the sink to all other nodes in the networks. In data forwarding, the packet is routed from sensor
to sink in a hop- by-hop fashion. Each next hop is determined independently. The main problem
with CARP is that it does not support reusability of previously collected data. In other words, if
the application requires sensor data only when it changes significantly, then CARP
dataforwarding is not beneficial to that specific application. An enhancement of CARP was done
in E-CARP by allowing the sink node to save previously received sensory data. When new data
is needed, E-CARP sends a Ping packet which is replied with the data from the sensors nodes.
Thus, E-CARP reduces the communication overhead drastically [Shou15].
22. Network Layer Encapsulation Protocols
• One problem in IoT applications is that IPv6 addresses are too long
and cannot fit in most IoT datalink frames which are relatively much
smaller. Hence, IETF is developing a set of standards to encapsulate
IPv6 datagrams in different datalink layer frames for use in IoT
applications. In this section, we review these mechanisms briefly.
23. 6LoWPAN
• IPv6 over Low power Wireless Personal Area Network (6LoWPAN) is
the first and most commonly used standard in this category. It
efficiently encapsulates IPv6 long headers in IEEE802.15.4 small
packets, which cannot exceed 128 bytes. The specification supports
different length addresses, low bandwidth, different topologies
including star or mesh, power consumption, low cost, scalable
networks, mobility, unreliability and long sleep time.
24. 6TiSCH
• 6TiSCH working group in IETF is developing standards
to allow IPv6 to pass through TimeSlotted Channel
Hopping (TSCH) mode of IEEE 802.15.4e datalinks. It
defines a Channel Distribution usage matrix consisting
of available frequencies in columns and time-slots
available for network scheduling operations in rows.
This matrix is portioned into chucks where each chunk
contains time and frequencies and is globally known
to all nodes in the network.
25. Session Layer Protocols
• This section reviews standards and protocols for message passing in
IoT session layer proposed by different standardization organizations.
Most of the IP applications, including IoT applications use TCP or UDP
for transport. However, there are several message distribution
functions that are common among many IoT applications; it is
desirable that these functions be implemented in an interoperable
standard ways by different applications. These are the so called
“Session Layer” protocols described in this section.
26. MQTT
• Message Queue Telemetry Transport (MQTT) was introduced by IBM in 1999
and standardized by OASIS in 2013 [Locke10 , Karagiannis15]. It is designed to
provide embedded connectivity between applications and middleware’s on
one side and networks and communications on the other side. It follows a
publish/subscribe architecture, as shown in Figure 5 , where the system
consists of three main components: publishers, subscribers, and a broker.
From IoT point of view, publishers are basically the lightweight sensors that
connect to the broker to send their data and go back to sleep whenever
possible. Subscribers are applications that are interested in a certain topic, or
sensory data, so they connect to brokers to be informed whenever new data
are received. The brokers classify sensory data in topics and send them to
subscribers interested inthe topics
27.
28. SMQTT
• An extension of MQTT is Secure MQTT (SMQTT) which uses encryption based
on lightweight attribute based encryption. The main advantage of using such
encryption is the broadcast encryption feature, in which one message is
encrypted and delivered to multiple other nodes, which is quite common in
IoT applications. In general, the algorithm consists of four main stages: setup,
encryption, publish and decryption. In the setup phase, the subscribers and
publishers register themselves to the broker and get a master secret key
according to their developer’s choice of key generation algorithm. Then, when
the data is published, it is encrypted, published by the broker which sends it
to the subscribers and finally decrypted at the subscribers which have the
same master secret key. The key generation and encryption algorithms are not
standardized. SMQTT is proposed only to enhance MQTT security feature
[Singh15].
29. AMQP
The Advanced Message Queuing Protocol (AMQP) is another session
layer protocol that was designed for financial industry. It runs over TCP
and provides a publish/ subscribe architecture which is similar to that
of MQTT. The difference is that the broker is divided into two main
components: exchange and queues, as shown in Figure 6. The exchange
is responsible for receiving publisher messages and distributing them
to queues based on pre-defined roles and conditions. Queues basically
represent the topics and subscribed by subscribers which will get the
sensory data whenever they are available in the queue [AMQP12].
30.
31. CoAP
The Constrained Application Protocol (CoAP) is another session layer protocol
designed by IETF Constrained RESTful Environment (Core) working group to
provide lightweight RESTful (HTTP) interface. Representational State Transfer
(REST) is the standard interface between HTTP client and servers. However, for
lightweight applications such as IoT, REST could result in significant overhead
and power consumption. CoAP is designed to enable low-power sensors to use
RESTful services while meeting their power constrains. It is built over UDP,
instead of TCP commonly used in HTTP and has a light mechanism to provide
reliability. CoAP architecture is divided into two main sublayers: messaging and
request/response. The messaging sublayer is responsible for reliability and
duplication of messages while the request/response sublayer is responsible for
communication. As shown in Figure 7 , CoAP has four messaging modes:
confirmable, non- confirmable, piggyback and separate
32. CoAP
• Confirmable and nonconfirmable modes represent the reliable and
unreliable transmissions, respectively while theother modes are used
for request/response. Piggyback is used for client/server direct
communication where the server sends its response directly after
receiving the message, i.e., within the acknowledgment message. On
the other hand, the separate mode is used when the server response
comes in a message separate from the acknowledgment, and may
take some time to be sent by the server. As in HTTP, CoAP utilizes GET,
PUT, PUSH, DELETE messages requests to retrieve, create, update,
and delete, respectively
33.
34. XMPP
• Extensible Messaging and Presence Protocol (XMPP) is a messaging protocol that
was designed originally for chatting and message exchange applications. It was
standardized by IETF more than a decade ago. Hence, it is well known and has
proven to be highly efficient over the internet. Recently, it has been reused for
IoT applications as well as a protocol for SDN. This reusing of the same standard is
due to its use of XML which makes it easily extensible. XMPP supports both
publish/ subscribe and request/ response architecture and it is up to the
application developer to choose which architecture to use. It is designed for near
real-time applications and, thus, efficiently supports low-latency small messages.
It does not provide any quality of service guarantees and, hence, is not practical
for M2M communications. Moreover, XML messages create additional overhead
due to lots of headers and tag formats which increase the power consumption
that is critical for IoT application. Hence, XMPP is rarely used in IoT but hasgained
some interest for enhancing its architecture in order to support IoT applications.