Network Components

Introduction to Networking
Introduction to Networks v7.0
(ITN)
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Objectives
Explain the advances in modern technologies.

AssignmentTutorOnline

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Network Components
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Network Components
Host Roles
Every computer on a network is
called a host or end device.
Servers are computers that provide
information to end devices:
• email servers
• web servers
• file server
Clients are computers that send
requests to the servers to retrieve
information:
• web page from a web server
• email from an email server

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Network Components
Peer-to-Peer
It is possible to have a device be a client and a server in a Peer-to-Peer Network. This type of
network design is only recommended for very small networks.

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Network Components
End Devices
An end device is where a message originates from or where it is received. Data
originates with an end device, flows through the network, and arrives at an end
device.
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Network Components
Intermediary Network Devices
An intermediary device interconnects end devices. Examples include
switches, wireless access points, routers, and firewalls.
Management of data as it flows through a network is also the role of an
intermediary device, including:
• Regenerate and retransmit data signals.
• Maintain information about what pathways exist in the network.
• Notify other devices of errors and communication failures.
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Network Components
Network Media
Communication across a network is carried through a medium which allows
a message to travel from source to destination.

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Network Representations and
Topologies
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Network Representations and Topologies
Network Representations
Network diagrams, often called
topology diagrams, use symbols to
represent devices within the network.
Important terms to know include:
• Network Interface Card (NIC)
• Physical Port
• Interface
Note: Often, the terms port and
interface are used interchangeably
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Network Representations and Topologies
Topology Diagrams
Physical topology diagrams illustrate
the physical location of intermediary
devices and cable installation.
Logical topology diagrams illustrate
devices, ports, and the addressing
scheme of the network.
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Common Types of Networks
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Common Types of Networks
Networks of Many Sizes
• Small Home Networks – connect a few
computers to each other and the Internet
• Small Office/Home Office – enables
computer within a home or remote office
to connect to a corporate network
• Medium to Large Networks – many
locations with hundreds or thousands of
interconnected computers
• World Wide Networks – connects
hundreds of millions of computers worldwide – such as the internet
Small Home SOHO
Medium/Large World Wide
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Common Types of Networks
LANs and WANs
Network infrastructures vary greatly
in terms of:
• Size of the area covered
• Number of users connected
• Number and types of services
available
• Area of responsibility
Two most common types of
networks:
• Local Area Network (LAN)
• Wide Area Network (WAN).
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Common Types of Networks
LANs and WANs (cont.)
A LAN is a network infrastructure that
spans a small geographical area.
A WAN is a network infrastructure that
spans a wide geographical area.

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Common Types of Networks
The Internet
The internet is a worldwide collection of
interconnected LANs and WANs.
• LANs are connected to each other using
WANs.
• WANs may use copper wires, fiber optic
cables, and wireless transmissions.
The internet is not owned by any individual or
group. The following groups were developed to
help maintain structure on the internet:
• IETF
• ICANN
• IAB
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Common Types of Networks
Intranets and Extranets
An intranet is a private collection of LANs
and WANs internal to an organization that
is meant to be accessible only to the
organizations members or others with
authorization.
An organization might use an extranet to
provide secure access to their network for
individuals who work for a different
organization that need access to their
data on their network.
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Internet Connections
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Internet Connections
Internet Access Technologies There are many ways to connect users
and organizations to the internet:
• Popular services for home users and
small offices include broadband cable,
broadband digital subscriber line
(DSL), wireless WANs, and mobile
services.
• Organizations need faster connections
to support IP phones, video
conferencing and data center storage.
• Business-class interconnections are
usually provided by service providers
(SP) and may include: business DSL,
leased lines, and Metro Ethernet.
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Internet Connections
Home and Small Office Internet Connections

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Internet Connections
Businesses Internet Connections
Corporate business connections may
require:
• higher bandwidth
• dedicated connections
• managed services

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Internet Connections
The Converging Network
Before converged networks, an
organization would have been
separately cabled for telephone,
video, and data. Each of these
networks would use different
technologies to carry the signal.
Each of these technologies would
use a different set of rules and
standards.
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Internet Connections
The Converging Network (Cont.)
Converged data networks carry
multiple services on one link
including:
• data
• voice
• video
Converged networks can deliver
data, voice, and video over the
same network infrastructure. The
network infrastructure uses the
same set of rules and standards.
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Reliable Networks
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Reliable Network
Network Architecture
Network Architecture refers to the
technologies that support the
infrastructure that moves data across
the network.
There are four basic characteristics that
the underlying architectures need to
address to meet user expectations:
• Fault Tolerance
• Scalability
• Quality of Service (QoS)
• Security
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Reliable Network
Fault Tolerance
A fault tolerant network limits the impact of
a failure by limiting the number of affected
devices. Multiple paths are required for
fault tolerance.
Reliable networks provide redundancy by
implementing a packet switched network:
• Packet switching splits traffic into
packets that are routed over a network.
• Each packet could theoretically take a
different path to the destination.
This is not possible with circuit-switched
networks which establish dedicated
circuits.
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Reliable Network
Scalability
A scalable network can expand
quickly and easily to support
new users and applications
without impacting the
performance of services to
existing users.
Network designers follow
accepted standards and
protocols in order to make the
networks scalable.
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Reliable Network
Quality of Service
Voice and live video transmissions require
higher expectations for those services
being delivered.
Have you ever watched a live video with
constant breaks and pauses? This is
caused when there is a higher demand for
bandwidth than available – and QoS isn’t
configured.
• Quality of Service (QoS) is the primary
mechanism used to ensure reliable
delivery of content for all users.
• With a QoS policy in place, the router
can more easily manage the flow of data
and voice traffic.
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Reliable Network
Network Security
There are two main types of network
security that must be addressed:
• Network infrastructure security
• Physical security of network devices
• Preventing unauthorized access to the
devices
• Information Security
• Protection of the information or data
transmitted over the network
Three goals of network security:
• Confidentiality – only intended
recipients can read the data
• Integrity – assurance that the data has
not be altered with during transmission
• Availability – assurance of timely and
reliable access to data for authorized
users
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Network Trends
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Network Trends
Recent Trends
The role of the network must
adjust and continually transform
in order to be able to keep up
with new technologies and end
user devices as they constantly
come to the market.
Several new networking trends
that effect organizations and
consumers:
• Bring Your Own Device
(BYOD)
• Online collaboration
• Video communications
• Cloud computing
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Network Trends
Bring Your Own Device Bring Your Own Device (BYOD) allows
users to use their own devices giving them
more opportunities and greater flexibility.
BYOD allows end users to have the
freedom to use personal tools to access
information and communicate using their:
• Laptops
• Netbooks
• Tablets
• Smartphones
• E-readers
BYOD means any device, with any
ownership, used anywhere.
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Network Trends
Online Collaboration
Collaborate and work with others
over the network on joint projects.
Collaboration tools including Cisco
WebEx (shown in the figure) gives
users a way to instantly connect and
interact.
Collaboration is a very high priority
for businesses and in education.
Cisco Webex Teams, Microsoft
Teams, Zoom, Skype are
multifunctional collaboration tools.
• send instant messages
• post images
• post videos and links
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Network Trends
Video Communication
• Video calls are made to anyone, regardless of where they are
located.
• Video conferencing is a powerful tool for communicating with
others.
• Video is becoming a critical requirement for effective collaboration.
• Cisco TelePresence is one example of working where everyone,
everywhere.
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Network Trends
Cloud Computing
Cloud computing allows us to store personal files or backup our data on servers over
the internet.
• Applications can also be accessed using the Cloud.
• Allows businesses to deliver to any device anywhere in the world.
Cloud computing is made possible by data centers.
• Smaller companies that cannot afford their own data centers, lease server and
storage services from larger data center organizations in the Cloud.
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Network Trends
Cloud Computing (Cont.)
Four types of Clouds:
• Public Clouds
Available to the general public through a pay-per-use model or for free.
• Private Clouds
Intended for a specific organization or entity such as the government.
• Hybrid Clouds
Made up of two or more Cloud types – for example, part custom and part public.
Each part remains a distinctive object but both are connected using the same architecture.
• Custom Clouds
Built to meet the needs of a specific industry, such as healthcare or media.
Can be private or public.
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Network Trends
Technology Trends in the Home
• Smart home technology is a
growing trend that allows
technology to be integrated into
every-day appliances which allows
them to interconnect with other
devices.
• Ovens might know what time to
cook a meal for you by
communicating with your calendar
on what time you are scheduled to
be home.
• Smart home technology is currently
being developed for all rooms
within a house.
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Network Trends
Powerline Networking
• Powerline networking can
allow devices to connect to a
LAN where data network
cables or wireless
communications are not a
viable option.
• Using a standard powerline
adapter, devices can connect
to the LAN wherever there is
an electrical outlet by sending
data on certain frequencies.
• Powerline networking is
especially useful when
wireless access points
cannot reach all the devices
in the home.
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Network Trends
Wireless Broadband In addition to DSL and cable, wireless is
another option used to connect homes and
small businesses to the internet.
• More commonly found in rural
environments, a Wireless Internet Service
Provider (WISP) is an ISP that connects
subscribers to designated access points or
hotspots.
• Wireless broadband is another solution for
the home and small businesses.
• Uses the same cellular technology used by
a smart phone.
• An antenna is installed outside the house
providing wireless or wired connectivity for
devices in the home.
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Summary
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Summary
What did I learn?
• Through the use of networks, we are connected like never before.
• All computers that are connected to a network and participate directly in network communication
are classified as hosts.
• Diagrams of networks often use symbols to represent the different devices and connections that
make up a network.
• A diagram provides an easy way to understand how devices connect in a large network.
• The two types of network infrastructures are Local Area Networks (LANs), and Wide Area
Networks (WANs).
• SOHO internet connections include cable, DSL, Cellular, Satellite, and Dial-up telephone.
• Business internet connections include Dedicated Leased Line, Metro Ethernet, Business DSL,
and Satellite.
• Network architecture refers to the technologies that support the infrastructure and the
programmed services and rules, or protocols, that move data across the network.
• There are four basic characteristics of network architecture: Fault Tolerance, Scalability, Quality
of Service (QoS), and Security.
• Recent networking trends that affect organizations and consumers: Bring Your Own Device
(BYOD), online collaboration, video communications, and cloud computing.