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Communications in a Connected World

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Module 1:
Communications in a
Connected World
Networking Basics (BNET)

Module Objectives
Module Title: Communications in a Connected World
Module Objective: Explain important concepts in network communication.
Topic Title
Topic Objective
Network Types
Explain the concept of a network.
Data Transmission
Describe network data.
Bandwidth and Throughput
Explain network transmission and speed and capacity.
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3.

1.1 Network Types
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4.

Network Types
Video - Welcome to the World of Networking
This video makes a short presentation about the world of networking.
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5.

Network Types
Everything is Online
How many of us still think about whether or not we are “online”?
We expect our phones, tablets, laptops, and desktop computers to always connect to the global
internet.
We use this network to interact with friends, shop, share pictures and experiences and learn.
The internet has become such a part of everyday life that we almost take it for granted.
Typically, when people use the term internet, they are not referring to the physical connections in
the real world.
Instead, they think of it as a formless collection of connections. It is the “place” people go to find or
share information.
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6.

Network Types
Who Owns “The Internet”?
Any individual or group does not own the internet.
It is a worldwide collection of interconnected networks
cooperating to exchange information using common
standards.
Through telephone wires, fiber-optic cables, wireless
transmissions, and satellite links, internet users can
exchange information in various forms, as shown in the
figure.
Everything that you access online is located somewhere on
the global internet.
Social media sites, multiplayer games, messaging centers
that provide email, and online courses — all these internet
destinations connect to local networks that send and receive
information through the internet.
Think about all your daily interactions that require you to be
online.
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7.

Network Types
Local Networks
Local networks come in all sizes.
They can range from simple networks consisting of two computers to networks connecting
hundreds of thousands of devices.
Networks installed in small offices, or homes and home offices, are referred to as SOHO
networks.
SOHO networks let you share resources, such as printers, documents, pictures, and music,
between a few local users.
Large networks can advertise and sell products, order supplies, and communicate with customers.
Communication over a network is usually more efficient and less expensive than traditional forms
of communication, such as regular mail or long-distance phone calls.
Networks allow for rapid communication, such as email and instant messaging, and provide
consolidation and access to information stored on network servers.
Business and SOHO networks usually provide a shared connection to the internet.
The internet is considered a "network of networks" because it makes up thousands of connected
local networks.
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8.

Network Types
Local Networks (Cont.)
Small Home Networks
Small home networks connect a few computers to each other and the
internet.
Small Office and Home
Office Networks
The SOHO network allows computers in a home or remote office to connect
to a corporate network or access centralized, shared resources.
Medium to Large Networks
Medium to large networks, such as those used by corporations and schools,
can have many locations with hundreds or thousands of interconnected
hosts.
World Wide Networks
The internet is a network that connects hundreds of millions of computers
worldwide.
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9.

Network Types
Mobile Devices
The internet connects more computing devices than just desktop and laptop computers.
There are devices all around that you may interact with daily that connect to the internet (mobile
devices, home devices, and a variety of other connected devices).
Smartphone
It connects to the internet from almost anywhere. It combines the functions of many different
products, such as a telephone, camera, GPS receiver, media player, and touchscreen
computer.
Tablet
It also has the functionality of multiple devices like a smartphone. With the additional screen
size, they are ideal for watching videos and reading magazines or books. With on-screen
keyboards, users do many things they used to do on their laptop computer, such as
composing emails or browsing the web.
Smartwatch
It can connect to a smartphone to provide the user with alerts and messages. Additional
functions, such as heart rate monitoring and counting steps, like a pedometer, can help
people who are wearing the device to track their health.
Smart Glasses
A wearable computer in the form of glasses, such as Google Glass, contains a tiny screen
that displays information to the wearer, similar to a fighter pilot's Head-Up Display (HUD). A
small touchpad on the side allows the user to navigate menus
while
still
being
ableCiscotoConfidential
see
© 2020
Cisco and/or
its affiliates.
All rights reserved.
through the smart glasses.
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10.

Network Types
Connected Home Devices
Many things in your home can connect to the internet to be monitored and configured
remotely.
Security System
Many home items, such as security systems, lighting, and climate controls, can be
monitored and configured remotely using a mobile device.
Appliances
Household appliances such as refrigerators, ovens, and dishwashers can connect to the
internet, allowing the homeowner to power them on or off, monitor the appliance's status,
and be alerted to preset conditions, such as when the temperature in the refrigerator
rises above an acceptable level.
Smart TV
It can be connected to the internet to access content without needing TV service provider
equipment. Also, it can allow a user to browse the web, compose an email, or display
video, audio, or photos stored on a computer.
Gaming Console
Gaming consoles can connect to the internet to download games and play with friends
online.
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11.

Network Types
Other Connected Devices
There are also many connected devices found in the world outside your home that provide
convenience and valuable, or even vital, information.
Smart Cars
Many modern cars can connect to the internet to access maps, audio and video content, or
information about a destination. They can even send a text message or email if there is an
attempted theft or call for assistance in case of an accident. These cars can also connect to
smartphones and tablets to display information about the different engine systems, provide
maintenance alerts, or display the security system's status.
RFID Tags
Radiofrequency identification (RFID) tags can be placed in or on objects to track them or
monitor sensors for many conditions.
Sensors and
Actuators
Connected sensors provide temperature, humidity, wind speed, barometric pressure, and soil
moisture data. Actuators can then be automatically triggered based on current conditions. For
example, a smart sensor can periodically send soil moisture data to a monitoring station. The
monitoring station can then signal an actuator to begin watering. The sensor will continue to
send soil moisture data allowing the monitoring station to determine when to deactivate the
actuator.
Medical
Devices
Medical devices such as pacemakers, insulin pumps, and hospital
monitors provide users or
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medical professionals with feedback or alerts when vital signs are at specific levels.
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13.

14.

Data Transmission
The Bit
Did you know that computers and networks only work with binary digits, zeros, and ones?
It cannot be easy to imagine that all our data is stored and transmitted as bits.
Each bit can only have one of two possible values, 0 or 1.
The term bit is an abbreviation of “binary digit” and represents the smallest piece of data.
Humans interpret words and pictures computers to analyze only patterns of bits.
A bit is stored and transmitted as one of two possible discrete states.
This can include two directions of magnetization, two different voltage or current levels, two distinct
levels of light intensity, or any other physical system of two discrete states.
For example, a light switch can be either On or Off; in binary representation, these states
correspond to 1 and 0, respectively.
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Data Transmission
The Bit (Cont.)
Every input device (mouse, keyboard, voice-activated receiver) will translate human interaction into
binary code for the CPU to process and store.
Every output device (printer, speakers, monitors, etc.) will take binary data and translate it into
human-recognizable form.
Within the computer itself, all data is processed and stored as binary.
Computers use binary codes to represent and interpret letters, numbers, and special characters
with bits.
A commonly used code is ASCII, where each character represents eight bits.
For example:
• Capital letter: A = 01000001
• Number: 9 = 00111001
• Unique character: # = 00100011
Each group of eight bits, such as the representations of letters and numbers, is known as a byte.
The use of codes can represent almost any type of information digitally, including computer data,
graphics, photos, voice, video, and music.
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16.

Data Transmission
Common Methods of Data Transmission
After the data transforms into bits, it converts into signals sent across the network media to its
destination.
Media refers to the physical medium on which the signals are transmitted.
Examples of media are copper wire, fiber-optic cable, and electromagnetic waves through the air.
A signal consists of electrical or optical patterns transmitted from one connected device to another.
These patterns represent the digital bits (the data) and travel across the media from source to
destination as either a series of pulses of electricity, vibrations of light, or radio waves.
Signals may be converted many times before reaching the destination, as corresponding media
changes between source and destination.
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17.

Data Transmission
Common Methods of Data Transmission (Cont.)
There are three standard methods of signal
transmission used in networks:
• Electrical signals - Transmission is achieved
by representing data as electrical pulses on
copper wire.
• Optical signals - Transmission is achieved by
converting the electrical signals into light
pulses.
• Wireless signals - Transmission is achieved by
using infrared, microwave, or radio waves
through the air.
Most homes and small businesses transmit network
signals across copper wires (cables) or Wi-Fi-enabled
wireless connections.
More extensive networks employ fiber-optic cables to
carry signals for longer distances reliably.
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19.

Bandwidth and Throughput
Bandwidth
Streaming a movie or playing a multiplayer game requires reliable, fast connections.
Networks can transmit and receive bits at a very high rate to support high-bandwidth applications.
Different physical media support the transfer of bits at different speeds.
The data transfer rate is usually discussed in terms of bandwidth and throughput.
Bandwidth is the capacity of a medium to carry data.
Digital bandwidth measures the amount of data that can flow from one place to another in a given
amount of time.
Bandwidth measures the number of bits that are (theoretically) sent across the media in a second.
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20.

Bandwidth and Throughput
Bandwidth (Cont.)
Common bandwidth measurements are as follows:
• Thousands of bits per second (Kbps)
• Millions of bits per second (Mbps)
• Billions of bits per second (Gbps)
Physical media properties, current technologies, and the laws of physics all play a role in
determining available bandwidth.
The table shows the commonly used units of measure for bandwidth.
Unit of Bandwidth
Abbreviation
Equivalence
Bits per second
bps
1 bps = fundamental unit of bandwidth
Kilobits per second
Kbps
1 Kbps = 1,000 bps = 103 bps
Megabits per second
Mbps
1 Mbps = 1,000,000 bps = 106 bps
Gigabits per second
Gbps
1 Gbps = 1,000,000,000 bps = 109 bps
Terabits per second
Tbps
1 Tbps = 1,000,000,000,000 bps = 1012
bps
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21.

Bandwidth and Throughput
Throughput
Like bandwidth, throughput is the measure of the transfer of bits across the media over a given
period.
However, the throughput does not usually match the specified bandwidth due to several factors.
Many factors influence throughput, including:
The amount of data being sent and received over the connection
The types of data being transmitted
The latency created by the number of network devices encountered between the source and
destination
Latency refers to the time, including delays, for data to travel from one given point to another.
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22.

Bandwidth and Throughput
Throughput (Cont.)
Throughput measurements do not consider the validity or usefulness of the bits being transmitted
and received.
Many messages received through the network are not destined for specific user applications.
An example would be network control messages that regulate traffic and correct errors.
In an internetwork or network with multiple segments, throughput cannot be faster than the slowest
link of the path from sending device to the receiving device.
Even if all or most of the segments have high bandwidth, it will only take one part in the path with
lower bandwidth to create a slowdown of the throughput of the entire network.
Many online speed tests can reveal the throughput of an internet connection.
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24.

25.

Communications in a Connected World Summary
What Did I Learn in This Module?
The internet is a worldwide collection of interconnected networks cooperating to exchange information
using common standards.
Internet users can exchange information in various forms through telephone wires, fiber-optic cables,
wireless transmissions, and satellite links.
Small home networks connect a few computers to each other and the internet.
The SOHO network allows computers in a home or remote office to connect to a corporate network or
access centralized, shared resources.
Medium to large networks, such as those used by corporations and schools, can have many locations with
hundreds or thousands of interconnected hosts.
There are devices all around that you may interact with daily that connects to the internet.
These include mobile devices such as smartphones, tablets, smartwatches, and smart glasses.
Things in your home can connect to the internet, such as a security system, appliances, your smart TV,
and your gaming console.
Outside your home, there are smart cars, RFID tags, sensors and actuators, and even medical devices
which can be connected.
The categories used to classify types of personal data are volunteered data, observed data, and inferred
data.
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Communications in a Connected World Summary
What Did I Learn in This Module? (Cont.)
The term bit is an abbreviation of “binary digit” and represents the smallest piece of data.
Each bit can only have one of two possible values, 0 or 1.
There are three standard methods of signal transmission used in networks: electrical signals, optical
signals, and wireless signals.
Bandwidth is the capacity of a medium to carry data.
Digital bandwidth measures the amount of data that can flow from one place to another in a given amount
of time.
The number of bits (theoretically) sent across the media in a second typically measures bandwidth.
Common bandwidth measurements are thousands of bits per second (Kbps), millions of bits per second
(Mbps), and billions of bits per second (Gbps).
Throughput usually varies from the specified bandwidth.
Many factors influence throughput, including:
• The amount of data being sent and received over the connection
• The latency is created by the number of network devices encountered between the source and
destination.
Latency refers to the time, including delays, for data to travel from one given point to another.
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