Chapter-1 Basics of Networking Module-1

 Today’s world relies heavily on data and networking, which allows for the instant availability
of information from anywhere on the earth at any moment.
 Networking refers to interconnected computing devices that can exchange data and share
resources with each other.
 These networked devices use a system of rules, called communications protocols, to transmit
information over physical or wireless technologies.
 The data transferred between the hosts may be text, images, or videos, which are typically in the
form of binary bit streams.

NETWORK TYPES
 Computer networks are classified according to various parameters:
 1) Type of connection, 2) physical topology, and 3) reach of the network.
 These classifications are helpful in deciding the requirements of a network setup and
appropriate selection of a network type for the setup.

CONNECTION TYPES
 Depending on the way a host communicates with other hosts, computer networks are of two
types: Point-to-point and Point-to-multipoint.

(i) Point-to-point:
 Point-to-point connections are used to establish direct connections between two hosts.
 A day-to-day system such as a remote control for an air conditioner or television is a point to
point connection, where the connection has the whole channel dedicated to it only.

(ii)Point-to-multipoint: In a point-to-multipoint connection, more than two hosts share the same
link. This type of configuration is similar to the one-to-many connection type.
The channel is shared between the various hosts, either spatially or temporally.
Point-to multipoint connections find popular use in present-day networks, especially while
enabling communication between a massive numbers of connected devices.

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 PHYSICAL TOPOLOGY
 Depending on the physical manner in which communication paths between the hosts are
connected, computer networks can have the following four broad topologies: Star, Mesh, Bus,
and Ring.
(i) Star:

 In a star topology, every host has a point-to-point link to a central controller or hub.
 The hosts cannot communicate with one another directly; they can only do so through the
central hub.
 The hub acts as the network traffic exchange.
 For large-scale systems, the hub, essentially, has to be a powerful server to handle all the
simultaneous traffic flowing through it.
 In a star, each device needs only one link hence this topology is cheaper and easier to set up.
 The main advantages of the star topology are easy installation and the ease of fault
identification within the network.If one link fails, only that link is affected. All other links
remain active.
 The main disadvantage of this topology is if hub fails, the whole network fails.

(ii) Mesh:

 In a mesh topology, every host is connected to every other host using a dedicated link (in a
point-to-point manner).
 This implies that for n hosts in a mesh, there are a total of n(n−1)/2 dedicated full duplex links
between the hosts.
 This massive number of links makes the mesh topology expensive.
 However, it offers certain specific advantages over other topologies. Even if a link is down or
broken, the network is still fully functional as there remain other pathways for the traffic to flow
through.
 The second advantage is the security and privacy of the traffic as the data is only seen by the
intended recipients and not by all members of the network.

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(iii) Bus:

 A bus topology follows the point-to-multipoint connection. A backbone cable or bus serves as
the primary traffic pathway between the hosts.
 The hosts are connected to the main bus by drop lines or taps.
 The main advantage of this topology is the ease of installation.
 The main drawback of this topology is the difficulty in fault localization within the network.

(iv) Ring:

 A ring topology works on the principle of a point-to-point connection.

 In a ring topology, each device is linked to only its immediate neighbors.
 A signal is passed along the ring in one direction, from device to device, until it reaches its
destination.
 Fault identification and set up of the ring topology is quite simple and straightforward.
 Themain disadvantage of this system is the high probability of a single point of failure the
whole network goes down.

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NETWORK REACHABILITY
 Computer networks are divided into four broad categories based on network reachability:
personal area networks, local area networks, wide area networks, and metropolitan area
networks.

(i) Personal Area Networks (PAN):

 PANs, as the name suggests, are mostly restricted to individual usage.
 A good example of PANs may be connected wireless headphones, wireless speakers,
wireless keyboards, wireless mouse, and printers within a house.
 Generally, PANs are wireless networks, which make use of low-range and low-power
technologies such as Bluetooth.
 The reachability of PANs lies in the range of a few centimetres to a few meters.

(ii) Local Area Networks (LAN):

 A LAN is a collection of hosts linked to a single network through wired or wireless
connections.
 However, LANs are restricted to buildings, organizations, or campuses.
 Typically, the present-day data access rates within the LANs range from 100 Mbps to 1000
Mbps.
 Commonly used network components in a LAN are servers, hubs, routers, switches,
terminals, and computers.

(iii) Metropolitan Area Networks (MAN):

 The reachability of a MAN lies between that of a LAN and a WAN.
 Typically, MANs connect various organizations or buildings within a given geographic
location or city.
 An excellent example of a MAN is an Internet service provider (ISP) supplying Internet
connectivity to various organizations within a city.
 As MANs are costly, they may not be owned by individuals or even single organizations.

(iv) Wide Area Networks (WAN):

 WANs typically connect diverse geographic locations.
 However, they are restricted within the boundaries of a state or country.
 The data rate of WANs is in the order of a fraction of LAN’s data rate.
 Due to the long transmission ranges, WANs tend to have more errors and noise during
transmission and are very costly to maintain.

LAYERED NETWORK MODELS

 The intercommunication between hosts in any computer network, be it a large-scale or a
small-scale one, is built upon the premise of various task-specific layers.
 Two of the most commonly accepted and used traditional layered network models are the
open systems interconnection developed by the International Organization of Standardization
(ISO-OSI) reference model and the Internet protocol suite.

OSI Model
 The ISO-OSI model is a conceptual framework that partitions any networked communication
device into seven layers of abstraction, each performing distinct tasks based on the
underlying technology and internal structure of the hosts.
 These seven layers, from bottom-up, are as follows: 1) Physical layer, 2) Data link layer, 3)
Network layer, 4) Transport layer, 5) Session layer, 6) Presentation layer, and 7) Application
layer.

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 (i) Physical Layer:
 This is a media layer and is also referred to as layer 1 of the OSI model.
 The physical layer is responsible for taking care of the electrical and mechanical operations
of the host at the actual physical level.
 These operations include or deal with issues relating to signal generation, signal transfer, the
layout of cables, physical port layout, line impedances, and signal loss.
 This layer is responsible for the topological layout of the network (star, mesh, bus, or ring),
communication mode (simplex, duplex, full duplex), and bit rate control operations.
 The protocol data unit associated with this layer is referred to as a signal.

(ii) Data Link Layer:

 This is a media layer and layer 2 of the OSI model.
 The data link layer is mainly concerned with the establishment and termination of the
connection between two hosts, and the detection and correction of errors during communication
between two or more connected hosts.
 IEEE 802 divides the OSI layer 2 further into two sub-layers [2]: Medium access control
(MAC) and logical link control (LLC).
 MAC is responsible for access control and permissions for connecting networked devices;
whereas LLC is mainly tasked with error checking, flow control, and frame synchronization.
 The protocol data unit associated with this layer is referred to as a frame.

(iii) Network Layer:

 This layer is a media layer and layer 3 of the OSI model.
 It provides a means of routing data to various hosts connected to different networks through
logical paths called virtual circuits.
 These logical paths may pass through other intermediate hosts (nodes) before reaching the
actual destination host.
 The primary tasks of this layer include addressing, sequencing of packets, congestion control,
error handling, and Internetworking.
 The protocol data unit associated with this layer is referred to as a packet.

(iv) Transport Layer:

 This is layer 4 of the OSI model and is a host layer.
 The transport layer is tasked with end-to-end error recovery and flow control to achieve a
transparent transfer of data between hosts.
 This layer is responsible for keeping track of acknowledgments during variable-length data
transfer between hosts.
 In case of loss of data, or when no acknowledgment is received, the transport layer ensures that
the particular erroneous data segment is re-sent to the receiving host.
 The protocol data unit associated with this layer is referred to as a segment or datagram.

(v) Session Layer:

 This is the OSI model’s layer 5 and is a host layer.
 It is responsible for establishing, controlling, and terminating of communication between
networked hosts.
 The session layer sees full utilization during operations such as remote procedure calls and
remote sessions.
 The protocol data unit associated with this layer is referred to as data.

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(vi) Presentation Layer:
 This layer is a host layer and layer 6 of the OSI model.
 It is mainly responsible for data format conversions and encryption tasks such that the syntactic
compatibility of the data is maintained across the network, for which it is also referred to as the
syntax layer.
 The protocol data unit associated with this layer is referred to as data.

(vii) Application Layer:

 This is layer 7 of the OSI model and is a host layer.
 It is directly accessible by an end-user through software APIs (application program interfaces)
and terminals.
 Applications such as file transfers, FTP (file transfer protocol), e-mails, and other such
operations are initiated from this layer.
 The application layer deals with user authentication, identification of communication hosts,
quality of service, and privacy.
 The protocol data unit associated with this layer is referred to as data

A networked communication between two hosts following the OSI model is shown in below
Figure. Table 1 summarizes the OSI layers and their features, where PDU stands for protocol data
unit.

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Internet protocol suite
 The Internet protocol suite is yet another conceptual framework that provides levels of
abstraction for ease of understanding and development of communication and networked
systems on the Internet.
 However, the Internet protocol suite predates the OSI model and provides only four levels of
abstraction:
 1) Link layer, 2) Internet layer, 3) transport layer, and 4) application layer.
 This collection of protocols is commonly referred to as the TCP/IP protocol suite as the
foundation technologies of this suite are transmission control protocol (TCP) and Internet
protocol (IP).
 The Internet protocol suite or the TCP/IP protocol suite is sometimes also referred to as the
Department of Defence (DoD) model.

(i) Link Layer:

 The first and base layer of the TCP/IP protocol suite is also known as the network
interface layer.
 This layer is synonymous with the collective physical and data link layer of the OSI
model.
 It enables the transmission of TCP/IP packets over the physical medium.
 According to its design principles, the link layer is independent of the medium in use,
frame format, and network access, enabling it to be used with a wide range of
technologies such as the Ethernet, wireless LAN, and the asynchronous transfer mode
(ATM).

(ii) Internet Layer:

 Layer 2 of the TCP/IP protocol suite is somewhat synonymous to the network layer of the
OSI model.
 It is responsible for addressing, address translation, data packaging, data disassembly and
assembly, routing, and packet delivery tracking operations.

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  Some core protocols associated with this layer are address resolution protocol (ARP),
Internet protocol (IP), Internet control message protocol (ICMP), and Internet group
management protocol (IGMP).
 Traditionally, this layer was built upon IPv4, which is gradually shifting to IPv6, enabling
the accommodation of a much more significant number of addresses and security
measures.

(iii) Transport Layer:

 Layer 3 of the TCP/IP protocol suite is functionally synonymous with the transport layer
of the OSI model.
 This layer is tasked with the functions of error control, flow control, congestion control,
segmentation, and addressing in an end-to-end manner; it is also independent of the
underlying network.
 Transmission control protocol (TCP) and user datagram protocol (UDP) are the core
protocols upon which this layer is built, which in turn enables it to have the choice of
providing connection-oriented or connectionless services between two or more hosts or
networked devices.

(iv) Application Layer:

 The functionalities of the application layer, layer 4, of the TCP/IP protocol suite are
synonymous with the collective functionalities of the OSI model’s session, presentation,
and application layers.
 This layer enables an end-user to access the services of the underlying layers and defines
the protocols for the transfer of data.
 Hypertext transfer protocol (HTTP), file transfer protocol (FTP), simple mail transfer
protocol (SMTP), domain name system (DNS), routing information protocol (RIP), and
simple network management protocol (SNMP) are some of the core protocols associated
with this layer.
 A networked communication between two hosts following the TCP/IP model is shown in
below Figure.

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 Chapter-2Emergence of IoTModule-1

 The Internet of things (IoT) describes the network of physical things or objects—that are
embedded with sensors, software, and other technologies for the purpose of connecting and
exchanging data with other devices and systems over the Internet.
 IoT is an anytime, anywhere, and anything (as shown in Figure) network of Internet-
connected physical devices or systems capable of sensing an environment and affecting the
sensed environment intelligently.

 The miniaturization of electronics and the cheap affordability of technology are resulting in a
sudden increase of connected devices.
 The total number of connected devices globally is estimated to be around 25 billion. This
figure is projected to triple within a short span of 5 years by the year 2025.

 The huge variety of data is generated from a massive number of connected devices.
 The data may be images, videos, music, speech, text, numbers, binary codes, machine status,
banking messages, data from sensors and actuators, healthcare data, data from vehicles, home
automation system status and control messages, military communications, and many more.
 One of the best examples of miniaturization of electronics and the cheap affordability of
technology is the evolution of smartphones.
 In 1990’s, cellular technology was still expensive and which could be afforded only by a
select few.

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  Moreover, these particular devices had only the basic features of voice calling, text
messaging, and sharing of low-quality multimedia.
 Within the next 10 years, cellular technology had become common and easily affordable.
 With time, the features of these devices evolved, and many applications like messaging,
video calling, e-mails, games are added which works with packet-based Internet.
 The present-day mobile phones (commonly referred to as smartphones) are more or less
Internet-based.
 In line with this trend, other connected devices have rapidly increasing.
 As all technologies and domains are moving toward smart management of systems, the
number of sensor/actuator-based systems is rapidly increasing.
 This rise in number leads to a further rise in the number of Internet-connected devices.
 The original Internet intended for sending simple messages is now connected with all sorts of
“Things”.
 These things can be legacy devices, modern-day computers, sensors, actuators, household
appliances, toys, clothes, shoes, vehicles, cameras etc.
 This is generally achieved using low-power and low-form-factor embedded processors on-
board the “things” connected to the Internetthrough wireless or wired technologies.

Typically, IoT systems can be characterized by the following features:

• Associated architectures, which are also efficient and scalable.
• No ambiguity in naming and addressing.
• Massive number of constrained devices, sleeping nodes, mobile devices, and non-IP devices.
• Intermittent and often unstable connectivity.

 IoT have achieved faster and higher technology acceptance as compared to electricity and
telephony.

 According to an International Data Corporation (IDC) report, worldwide spending on IoT is

reported to have crossed USD 700 billion. The projected spending on IoTbased technologies
worldwide is estimated to be about USD 1.1 trillion.
 Similarly, the compounded annual growth rate of IoT between the years 2016 and 2021, as
depicted in Figure, shows that the majority of the market share is captured by consumer
goods, which is closely followed by insurance and healthcare industries.
 Figure above shows the IoT market share of various sectors. The manufacturing, logistics,
and asset management sectors are the largest receivers of IoT-linked investments in 2017.
Evolution of IoT
 The IoT, as we see it today, is a result of a series of technological shifts over a few decades.

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  The technological foundation of connected systems which makes it easy integration to daily
lives, popular public acceptance, and massive benefits by using connected solutions can be
considered as the founding solutions for the development of IoT.
 Figure shows the sequence of technical developments leading to the modern day IoT.

ATM:
 ATMs or automated teller machines are cash distribution machines, which are linked to a
user’s bank account.
 ATMs dispense cash upon verification of the identity of a user and their account through a
specially coded card.
 The central concept behind ATMs was the availability of financial transactions even when
banks were closed beyond their regular work hours.
 The first ATM became operational and connected online for the first time in 1974.

Web:
 World Wide Web is a global information sharing and communication platform.
 The Web became operational for the first time in 1991.
 Since then, it has been massively responsible for the many revolutions in the field of
computing and communication.

Smart Meters:
 The earliest smart meter was a power meter, which became operational in early 2000.
 These power meters were capable of communicating remotely with the power grid.
 They enabled remote monitoring of subscribers’ power usage and eased the process of billing
and power allocation from grids.

Digital Locks:
 Digital locks can be considered as one of the earlier attempts at connected home-automation
systems.
 Present-day digital locks are so robust that smartphones can be used to control them.
 Operations such as locking and unlocking doors, changing key codes, including new
members in the access lists, can be easily performed, and that too remotely using
smartphones.

Connected Healthcare:
 Here, healthcare devices connect to hospitals, doctors, and relatives to alert them of medical
emergencies and take preventive measures.
 The devices may be simple wearable appliances, monitoring just the heart rate and pulse of
the wearer, as well as regular medical devices and monitors in hospitals.

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  The connected nature of these systems makes the availability of medical records and test
results much faster, cheaper, and convenient for both patients as well as hospital authorities.

Connected Vehicles:
 Connected vehicles may communicate to the Internet or with other vehicles, or even with
sensors and actuators contained within it.
 These vehicles self-diagnose themselves and alert owners about system failures.

Smart Cities:
 This is a city-wide implementation of smart sensing, monitoring, and actuation systems.
 The city-wide infrastructure communicating amongst them enables synchronized operations
and information distribution.
 Some of the facilities which may benefit are parking, transportation, and others.

Smart Dust:
 These are microscopic computers.
 Smaller than a grain of sand each, they can be used in numerous beneficial ways, where
regular computers cannot operate.
 For example, smart dust can be sprayed to measure chemicals in the soil or even to diagnose
problems in the human body.

Smart Factories:
 These factories can monitor plant processes, assembly lines, distribution lines, and manage
factory floors all on their own.
 The reduction in mishaps due to human errors in judgment processes is drastically reduced.

UAVs:
 UAVs or unmanned aerial vehicles have emerged as robust publicdomain solutions tasked
with applications ranging from agriculture, surveys, surveillance, deliveries, stock
maintenance, asset management, and other tasks.

 The present-day IoT spans across various domains and applications.

 The major highlight of this is its ability to function as a cross-domain technology enabler.
Multiple domains can be supported and operated upon simultaneously over IoT-based
platforms.
 Support for legacy technologies and standalone along with modern developments, makes IoT
quite robust and economical for commercial, industrial, as well as consumer applications.
 IoT is being used in vivid and diverse areas such as smart parking, smartphone detection,
traffic congestion, smart lighting, waste management, smart roads, structural health, urban
noise maps, river floods, water flow, silos stock calculation, water leakages, radiation levels,
explosive and hazardous gases, perimeter access control, snowlevel monitoring, liquid
presence, forest fire detection, air pollution, smart grid, tank level, photovoltaic installations,
NFC (near-field communications) payments, intelligent shopping applications, landslide and
avalanche prevention, early detection of earthquakes, supply chain control, smart product
management, and others.
 Figure below shows the various technological interdependencies of IoT with other domains
and networking models such as M2M, CPS, the Internet of environment (IoE), the Internet of
people (IoP), and Industry 4.0.

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 (i) M2M:
 The M2M or the machine-to-machine model signifies a system of connected machines and
devices, which can talk amongst themselves without human intervention.
 The communication between the machines can be for updates on machine status (stocks,
health, power status, and others), collaborative task completion, overall knowledge of the
systems and the environment, and others.

(ii) CPS:
 The CPS or the cyber physical system model insinuates a closed control loop—from sensing,
processing, and finally to actuation—using a feedback mechanism.
 CPS helps in maintaining the state of an environment through the feedback control loop,
which ensures that until the desired state is attained, the system keeps on actuating and
sensing.
 Humans have a simple supervisory role in CPS-based systems; most of the ground-level
operations are automated.

(iii) IoE:
 The IoEmodelis mainly concerned with minimizing and even reversing the ill-effects of the
permeation of Internet-based technologies on the environment.
 The major focus areas of this model include smart and sustainable farming, sustainable and
energy-efficient habitats, enhancing the energy efficiency of systems and processes, and
others.
 In brief, we can safely assume that any aspect of IoT that concerns and affects the
environment falls under the purview of IoE.

(iv) Industry 4.0:

 Industry 4.0 is commonly referred to as the fourth industrial revolution pertaining to
digitization in the manufacturing industry.
 The previous revolutions chronologically dealt with mechanization, mass production, and the
industrial revolution, respectively.
 This model strongly puts forward the concept of smart factories, where machines talk to one
another without much human involvement based on a framework of CPS and IoT.
 The digitization and connectedness in Industry 4.0 translate to better resource and workforce
management, optimization of production time and resources, and better upkeep and lifetimes
of industrial systems.

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 (v) IoP:
 IoP is a new technological movement on the Internet which aims to decentralize online social
interactions, payments, transactions, and other tasks while maintaining confidentiality and
privacy of its user’s data.
 A famous site for IoP states that as the introduction of the Bitcoin has severely limited the
power of banks and governments, the acceptance of IoP will limit the power of corporations,
governments, and their spy agencies

IoT versus M2M

 M2M or the machine-to-machine model refers to communications and interactions
between various machines and devices.
 These interactions can be enabled through a cloud computing infrastructure, a server, or
simply a local network hub.
 M2M collects data from machinery and sensors, while also enabling device management
and device interaction.
 Telecommunication services providers introduced the term M2M, and technically
emphasized on machine interactions via one or more communication networks (e.g., 3G,
4G, 5G, satellite, public networks).
 M2M is part of the IoT and is considered as one of its sub-domains.
 However, in terms of operational and functional scope, IoT is vaster than M2M and
comprises a broader range of interactions such as the interactions between devices/things,
things, and people, things and applications, and people with applications.
 M2M enables the amalgamation of workflows comprising such interactions within IoT.

IoT versus CPS

 A Cyber physical system (CPS) encompasses sensing, control, actuation, and feedback
as a complete package.
 In other words, a digital twin is attached to a CPS-based system.
 As mentioned earlier, a digital twin is a virtual system–model relation, in which the
system signifies a physical system or equipment or a piece of machinery, while the
model represents the mathematical model or representation of the physical system’s
behavior or operation.
 Many a time, a digital twin is used parallel to a physical system, especially in CPS as it
allows for the comparison of the physical system’s output, performance, and health.
 Based on feedback from the digital twin, a physical system can be easily given corrective
directions/commands to obtain desirable outputs.
 In contrast, the IoTmodeldoes not compulsorily need feedback or a digital twin system.
 IoT is more focused on networking than controls.
 Some of the sub-systems in an IoT environment (such as those formed by CPS-based
instruments and networks) may include feedback and controls too.
 CPS may be considered as one of the sub-domains of IoT.

IoT versus WoT

 The Web of Things (WoT) model enables access and control over IoT resources and
applications.
 These resources and applications are generally built using technologies such as HTML 5.0,
JavaScript, Ajax, PHP, and others.
 REST (representational state transfer) is one of the key enablers of WoT.
 The use of RESTful principles and RESTful APIs (application program interface) enables
both developers and deployers to benefit from the recognition, acceptance, and maturity of
existing web technologies without having to redesign and redeploy solutions from scratch.

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  Still, designing and building the WoTmodel has various adaptability and security challenges,
especially when trying to build a globally uniform WoT.
 As IoT is focused on creating networks comprising objects, things, people, systems, and
applications, which often do not consider the unification aspect and the limitations of the
Internet, the need for WoT, which aims to integrate the various focus areas of IoT into the
existing Web is really invaluable.
 Technically, WoT can be thought of as an application layer-based hat added over the network
layer.
 However, the scope of IoT applications is much broader; IoT also which includes non-IP-
based systems that are not accessible through the web.

Enabling IoT and the Complex Interdependence of Technologies

 IoT is a model built upon complex interdependencies of technologies (both legacy and
modern), which occur at various planes of this model.
 In Figure below figure, we can divide the IoTmodel into four planes: services, local
connectivity, global connectivity, and processing.
 The service plane is composed of two parts: 1) things or devices and 2) low-power
connectivity.

 Typically, the services offered in this layer are a combination of things and lowpower
connectivity.
 AnyIoT application requires the basic setup of sensing, followed by rudimentary processing
(often), and a low-power, low-range network, which is mainly built upon the IEEE 802.15.4
protocol.
 The things may be wearables, computers, smartphones, household appliances, smart glasses,
factory machinery, vending machines, vehicles, UAVs, robots, and other such contraptions
(which may even be just a sensor).
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  The immediate low-power connectivity, which is responsible for connecting the things in
local implementation, may be legacy protocols such as WiFi, Ethernet, or cellular.
 In contrast, modern-day technologies are mainly wireless and often programmable such as
Zigbee, RFID, Bluetooth, 6LoWPAN, LoRA, DASH, Insteon, and others.
 The range of these connectivity technologies is severely restricted; they are responsible for
the connectivity between the things of the IoT and the nearest hub or gateway to access the
Internet.

 The local connectivity is responsible for distributing Internet access to multiple local IoT
deployments.
 This distribution may be on the basis of the physical placement of the things, on the basis of
the application domains, or even on the basis of providers of services.
 Services such as address management, device management, security, sleep scheduling, and
others fall within the scope of this plane.
 For example, in a smart home environment, the first floor and the ground floor may have
local IoT implementations, which have various things connected to the network via low-
power, low-range connectivity technologies.
 The traffic from these two floors merges into a single router or a gateway.
 The total traffic intended for the Internet from a smart home leaves through a single gateway
or router, which may be assigned a single global IP address (for the whole house).
 This helps in the significant conservation of already limited global IP addresses.
 The local connectivity plane falls under the scope of IoT management as it directly deals
with strategies to use/reuse addresses based on things and applications.
 The modern-day “edge computing” is deployed in conjunction with these first two planes:
services and local connectivity.

 The global connectivity plays a significant role in enabling IoT in the real sense by allowing
for worldwide implementations and connectivity between things, users, controllers, and
applications.
 This plane also falls under the scope of IoT management as it decides how and when to store
data, when to process it, when to forward it, and in which form to forward it.
 The Web, data-centers, remote servers, Cloud, and others make up this plane.
 The model of “fog computing” lies between the planes of local connectivity and global
connectivity.
 It often serves to manage the load of global connectivity infrastructure by offloading the
computation nearer to the source of the data itself, which reduces the traffic load on the
global Internet.

 The final plane of processing can be considered as a top-up of the basic IoT networking
framework.
 The continuous rise in the usefulness and spreading of IoT in various application areas such
as industries, transportation, healthcare, and others is the result of this plane.
 The members in this plane may be termed as IoT tools, simply because they provide useful
and human-readable information from all the raw data that flows from various IoT devices
and deployments.

 The various sub-domains of this plane include intelligence, conversion (data and format
conversion, and data cleaning), learning (making sense of temporal and spatial data patterns),
cognition (recognizing patterns and mapping it to already known patterns), algorithms
(various control and monitoring algorithms), visualization (rendering numbers and strings in
the form of collective trends, graphs, charts, and projections), and analysis (estimating the

Sandeep K.H Dept of CSE, PESITM-Shivamogga Page 16

 usefulness of the generated information, making sense of the information with respect to the
application and place of data generation, and estimating future trends based on past and
present patterns of information obtained).
 Various computing paradigms such as “big data”, “machine Learning”, and others, fall
within the scope of this domain.

IoT Networking Components

 An IoT implementation is composed of several components, which may vary with their
application domains.
 The broad components that come into play during the establishment of any IoT network, into
six types:
 1) IoT node, 2) IoT router, 3) IoT LAN, 4) IoT WAN, 5) IoT gateway, and 6) IoT proxy.
 A typical IoT implementation from a networking perspective is shown in Figure.
 The individual components are briefly described here:

(i) IoT Node:

 These are the networking devices within an IoT LAN.
 Each of these devices is typically made up of a sensor, a processor, and a radio, which
communicates with the network infrastructure (either within the LAN or outside it).
 The nodes may be connected to other nodes inside a LAN directly or by means of a common
gateway for that LAN. Connections outside the LAN are through gateways and proxies.

(ii) IoT Router:

 An I oT router is a networking device that is primarily tasked with the routing of packets
between various entities in the IoT network;
 it keeps the traffic flowing correctly within the network.
 A router can be remodel as a gateway by enhancing its functionalities.
Sandeep K.H Dept of CSE, PESITM-Shivamogga Page 17
 (iii) IoT LAN:
 The local area network (LAN) enables local connectivity within the single gateway.
 Consist of short-range connectivity technologies. IoT LANs may or may not be connected to
the Internet.
 Generally, they are localized within a building or an organization.

(iv) IoT WAN:

 The wide area network (WAN) connects various network segments such as LANs.
 They are typically organizationally and geographically wide, with their operational range
lying between a few kilometers to hundreds of kilometers.
 IoT WANs connect to the Internet and enable Internet access to the segments they are
connecting.

(v) IoT Gateway:

 An IoT gateway is simply a router connecting the IoT LAN to a WAN or the Internet.
 Gateways can implement several LANs and WANs.
 Their primary task is to forward packets between LANs and WANs, and the IP layer using
only layer 3.

(vi) IoT Proxy:

 Proxies actively lie on the application layer and performs application layer functions between
IoT nodes and other entities.
 Typically, application layer proxies are a means of providing security to the network entities
under it ;
 it helps to extend the addressing range of its network.
 In Figure, various IoT nodes within an IoT LAN are configured to to one another as well as
talk to the IoT router whenever they are in the range of it.
 The devices have locally unique (LU-x) device identifiers.
 These identifiers are unique only within a LAN.
 There is a high chance that these identifiers may be repeated in a new LAN.
 Each IoT LAN has its own unique identifier, which is denoted by IoT LAN-x in Figure.
 A router acts as a connecting link between various LANs by forwarding messages from the
LANs to the IoT gateway or the IoT proxy.
 As the proxy is an application layer device, it is additionally possible to include features such
as firewalls, packet filters, and other security measures besides the regular routing operations.
 Various gateways connect to an IoT WAN, which links these devices to the Internet.
 There may be cases where the gateway or the proxy may directly connect to the Internet.
 This network may be wired or wireless; however, IoT deployments heavily rely on wireless
solutions.
 This is mainly attributed to the large number of devices that are integrated into the network;
wireless technology is the only feasible and neat-enough solution to avoid the hassles of
laying wires and dealing with the restricted mobility rising out of wired connections.

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Assignment Questions

1. Differentiate between point-to-point and point-to-multipoint connection types.

2. Discuss the pros and cons of the following network topologies:
(a) Star (b) Ring (c) Bus (d) Mesh
3. How are PANs different from LANs?
4. How are MANs different from WANs?
5. What is the ISO-OSI model? Discuss the highlights of the seven layers of the OSI
stack.
6. What is the Internet protocol suite? How is the Internet protocol suite different from
the ISO-OSI model?
7. Define is IoT, smart dust & Web of Things (WoT)?
8. Differentiate between IoT and M2M.
9. Differentiate between IoT and WoT
10.Differentiate between an IoT proxy and an IoT gateway
11.What are the various IoT connectivity terminologies?

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