Wireless Network and Mobile Cumputing Tank you!

1. Overview of Wireless
Communication and Voice
Data
1
Chapter One
By Biruk.P (MSc)

2. Introduction
• Wireless
– is a term used to describe telecommunications in
which electromagnetic waves (rather than some
form of wire) carry the signal over part or all of the
communication path.
• Wireless transmission
– is a form of unguided media.
– involves no physical link established between two
or more devices, communicating wirelessly.
– A little part of electromagnetic spectrum can be
used for wireless transmission.
2
By Biruk.P (MSc)

3. History
• First wireless telephone conversation
occurred in 1880
• Alexander Graham Bell and Charles Sumner
Tainter invented and patented the photophone
• Photophone:
– telephone that conducted audio
conversations wirelessly over modulated
light beams (which are narrow projections
of electromagnetic waves)
3
By Biruk.P (MSc)

4. Wireless Communication
• Wireless Communication
– incorporates all procedures and forms of
connecting and communicating between two or
more devices using a wireless signal
through wireless communication technologies and
devices.
– is a type of data communication that is performed
and delivered wirelessly.
4
By Biruk.P (MSc)

5. • Satellite Communication
• Infrared Communication
• Broadcast Radio
• Microwave Communication
• Wi-Fi Communication
• Mobile Communication Systems
• Bluetooth Technology
5
Types of Wireless Communication
By Biruk.P (MSc)

6. 1. Satellite Communication
– self contained wireless communication technology,
– it is widely spread all over the world to allow users to stay
connected
– satellite amplifies the signal and sent it back to the
antenna receiver which is located on the surface of the
earth.
2. Infrared Communication
– communicates information in a device or systems through
IR radiation .
– IR is electromagnetic energy at a wavelength that is longer
than that of red light.
– It is used for security control, TV remote control and short
range communications.
6
Cont..
By Biruk.P (MSc)

7. 3. Broadcast Radio
– The first wireless communication technology
– Radio waves are electromagnetic signals, that are
transmitted by an antenna.
– These waves have completely different frequency
segments, and you will be ready to obtain an audio
signal by changing into a frequency segment.
7
By Biruk.P (MSc)

8. 4. Microwave Communication
– an effective type of communication, mainly this
transmission uses radio waves, and the wavelengths
of radio waves are measured in centimeters.
– data or information can be transfers using satellite
method and terrest
– In satellite method, the data can be transmitted
though a satellite, that orbit 22,300 miles above the
earth.
– In terrestrial method, in which two microwave towers
with a clear line of sight between them are used,
ensuring no obstacles to disrupt the line of sight.
– used for the purpose of privacy.
– The frequency range typically 4GHz-6GHz and with a
transmission speed is usually 1Mbps to 10Mbps.
– disadvantage of microwave signals is, they can be
8
By Biruk.P (MSc)

9. 5. Wi-Fi Communication
– low power wireless communication, that is
used by various electronic devices like smart
phones, laptops, etc.
– In this setup, a router works as a
communication hub wirelessly.
– allow users to connect only within close
proximity to a router.
– WiFi is very common in networking
applications
– These networks need to be protected with
passwords for the purpose of security,
otherwise it will access by others
9
By Biruk.P (MSc)

10. 6. Mobile Communication Systems
– The advancement of mobile networks is
enumerated by generations.
– Many users communicate across a single
frequency band through mobile phones.
– Cellular and cordless phones are two examples of
devices which make use of wireless signals.
– Typically, cell phones have a larger range of
networks to provide a coverage.
– But, Cordless phones have a limited range. Similar
to GPS devices, some phones make use of signals
from satellites to communicate.
10
By Biruk.P (MSc)

11. 7. Bluetooth Technology
– permits you to connect a various electronic devices
wirelessly to a system for the transferring of data.
– used commonly in the wireless communication
market.
11
By Biruk.P (MSc)

12. Types of wireless Devices
• Wireless technology describes electronic
devices that communicate without cords
using radio frequency signals.
• Wireless technology is used in a variety of
modern device to provide convenience and
greater mobility
• wireless devices play an important role in
voice and Internet communications.
12
By Biruk.P (MSc)

13. • is a device that accepts an incoming Internet
connection and sends data as RF signals to
other wireless devices that are near the
router.
• used to connect wireless-enabled computers
and other devices to the Internet.
• A network set up with a wireless router is
sometimes called a wireless local area
network (WLAN.).
• Many routers have built-in security features
such as firewalls which help protect devices
connected to the router against malicious
data, such as computer viruses
13
Wireless Router
By Biruk.P (MSc)

14. Wireless Adapter
• are hardware devices installed inside
computers that enable wireless
connectivity.
• If a computer does not have a wireless
adapter, it will not be able to connect to a
router in order to access the Internet.
• Some computers have wireless adapters
built directly into the motherboard while it
is also possible to install stand-alone
wireless adapters to add wireless
capability to a computer that did not come
with an adapter built in.
14
By Biruk.P (MSc)

15. • is a wireless networking device that is used to
extend the range of a router.
• A repeater receives wireless signals and then re-
emits them with increased strength.
• By placing a repeater between a router and the
computer connected to the router, signal strength
can be boosted, resulting in faster connection
speeds.
15
Wireless Repeater
By Biruk.P (MSc)

16. Wireless Phones
16
• Cellular and cordless phones are two more examples
of device that make use of wireless signals.
• Cordless phones have a limited range, but cell
phones typically have a much larger range than local
wireless networks, since cell phone providers use
large telecommunication towers to provide cell phone
coverage.
• Satellite phones make use of signals from satellites to
communicate, similar to Global Positioning System
(GPS) devices.
By Biruk.P (MSc)

17. Advantage of Wireless Communication
• Any data or information can be transmitted
faster and with a high speed
• Maintenance and installation is less cost for
these networks.
• The internet can be accessed from anywhere
wirelessly
• It is very helpful for workers, doctors working
in remote areas as they can be in touch with
medical centers.
17
By Biruk.P (MSc)

18. Disadvantage of Wireless Communication
• An unauthorized person can easily capture the
wireless signals which spread through the air.
• It is very important to secure the wireless
network so that the information cannot be
misused by unauthorized users
18
By Biruk.P (MSc)

19. Telecommunication
• is the electronic exchange of any type of data
over a wide variety of information transmitting
technologies and systems
• the transmission of signals, messages, words,
writings, images and sounds or information of
any nature by wire, radio, optical or other
electromagnetic systems.
• occurs when the exchange of information
between communication participants includes
the use of technology
• communication over a distance by cable,
telegraph, telephone, or broadcasting.
19
By Biruk.P (MSc)

20. Wireless Communication Protocols
Wireless Communication Protocol
• is a standard set of rules with reference to
which various electronic devices communicate
with each other wirelessly
• there are many wireless
communication protocols available to use
• Some of them are:
– Wi-Fi
– Bluetooth
– ZigBee
– Z-Wave
– 6LoWPAN
– RFID
– 5G etc 20
By Biruk.P (MSc)

21. • Wi-Fi (Wireless Fidelity)
– is the most popular communication protocols
for wireless local area network (WLAN)
– It utilizes the IEEE 802.11 standard through 2.4
GHz and 5 GHz frequencies
– It provides Internet access to devices that are
within the range of about 20 - 40 meters from
the source
– It has a data rate up to 600 Mbps maximum,
depending on channel frequency used and the
number of antennas
– The infrastructure or device cost for Wi-Fi is
low & deployment is easy but the power
consumption is high and the Wi-Fi range is
quite moderate
21
By Biruk.P (MSc)

22. • Bluetooth
– Bluetooth is a global 2.4 GHz personal area network
for short-range wireless communication(50 – 150
meters)
– The data is being shared at a maximum data rate of
1 Mbps
– Device-to-device file transfers, wireless speakers,
and wireless headsets are often enabled with
Bluetooth.
• ZigBee
– Has features similar to Bluetooth technology
– It follows IEEE 802.15.1 standards
– It is a 2.4 GHz mesh local area network (LAN) 22
By Biruk.P (MSc)

23. 23
– It was originally designed for building automation
and control—so things like wireless thermostats (a
device that automatically regulate temperature) and
lighting systems often use ZigBee (10-100 meters)
– Data rate to transfer data between device is around
250kbps
• Z-Wave
– Known as a low-power RF technology
– Data Packets are exchanged at data rates of
100kbps
– Operate at a frequency of 900MHz
– Distance range of up to 30 meters maximum
By Biruk.P (MSc)

24. • 6LoWPAN (IPv6 Wireless Personal Area
Network)
– Consumes Low power
– It uses a lightweight IP-based communication to
travel over lower data rate networks.
– It is an open IoT network protocol like ZigBee, and
it is primarily used for home and building
automation
– Supports data encapsulation and header
compression
• RFID(Radio frequency identification)
– Use electromagnetic fields to identify objects or
tags(which contains some stored information)
– Has a range of 10cm - short range and 200m long
range distance
24
By Biruk.P (MSc)

25. – It starts from KHz and ranges till GHz or can be said
as frequency ranges from low frequency (LF) – to
microwave depending up on the app and distance
of communication
• Thread
– Thread is an open standard, built on IPv6 and
6LoWPAN protocols.
– You could think of it as Google’s version of ZigBee
– You can actually use some of the same chips for
Thread and ZigBee, because they’re both based on
802.15.4
25
By Biruk.P (MSc)

26. • Cellular
– Has been in use since the last 2 decades
– Used for long distance communications
– Data can be sent of large size and with high
speeds
– Operating frequencies range from 900-2100MHz
– Cover distance of 35km to 200 km
– Data rates form 35kbps to 10Mbps
– Comprises of 2G, 3G, 4G
• 2G (GSM-Global system or standard for
Mobile)
– 2G is the “old-school” TDMA (usually) cellular 26
By Biruk.P (MSc)

27. – ATMs and old alarm systems used this— and in most
parts of the world it is phased out or in the process of
being phased out.
• 3G & 4G
– 3G was the first “high speed” cellular network,
and is a name that refers to a number of
technologies that meet IMT-2000 standards.
– 4G is the generation of cellular standards that
followed 3G, and is what most people use today
for mobile cellular data.
– You can use 3G and 4G for IoT devices, but the
application needs a constant power source or
must be able to be recharged regularly
27
By Biruk.P (MSc)

28. • 5G
– 5G is the fifth generation of cellular network protocol
– It’s designed for high speeds communication between
Smartphone's as well as other devices (unlike the
other cellular networks)
– The download speed is expected to be around 1Gbps
on average
– The technology protocol will work alongside with 3G
& 4G technologies and would have a huge rise in
Internet of Things (IOT) technology
– The technology has launched in 2019 for test
purposes and is available only in a few cities of the
world
– But it is planned to launch worldwide in 2020
28
By Biruk.P (MSc)

29. Wireless considerations for a data
communications strategy
• Wireless data communication is a technology that
uses the radio spectrum to transmit signals through
the atmosphere. It may carry analog or digital
signals and can be used on LANs or WANs in one-
or two-way networks. Specific wireless data
communication applications and technologies
transmit signals through distinct segments of the
radio spectrum (between the frequencies of 30 Hz
and 300 GHz).
29
By Biruk.P (MSc)

30. cdpd in wireless communication
 Cellular digital packet data (CDPD)
 a wireless data service used to access the Internet and
other packet-switched systems over a cellular network
specialized mobile radio (SMR)
 was first established by the Wireless Radio Commission
(part of the Federal Communications Commission [FCC])
in 1979 to provide land/mobile communications on a
commercial basis.
 An SMR system consists of the following:
• One or more base station transmitters
• One or more antennas
• End user radio equipment that usually consists of a mobile
radio unit, either provided by the end user or obtained
from the SMR operator for a fee
30
By Biruk.P (MSc)

31. Commercial mobile data communications services
• A mobile data connection enables a user to
access the same internet resources over a
cellular network owned by a telecommunications
provider.
• Mobile data is internet content delivered to mobile
devices such as smartphones and tablets over
a wireless cellular connection.
• Mobile data creates a wireless connection by
enabling devices to communicate through radio
frequencies.
31
By Biruk.P (MSc)

32. Satellite data wireless LANS
• The process of satellite communication begins at an earth
station. Here an installation is designed to transmit and
receive signals from a satellite in orbit around the earth.
• A communication satellite is a microwave repeater
station in a space that is used for telecommunication,
radio and television signals. A communication satellite
processes the data coming from one earth station and it
converts the data into another form and send it to the
second earth station.
How a Satellite Works?
• Two stations on earth want to communicate through radio
broadcast but are too far away to use conventional means.
The two stations can use a relay station for their
communication. One earth station transmits the signal to
the satellite.
32
By Biruk.P (MSc)

33. Advantages of Satellite
• The advantages of Satellite Communications are as
follows −
• The Coverage area is very high than that of terrestrial
systems.
• The transmission cost is independent of the coverage
area.
• Higher bandwidths are possible.
Disadvantages of Satellite
• The disadvantages of Satellite Communications are as
follows −
• Launching satellites into orbits is a costly process.
• The bandwidths are gradually used up.
• High propagation delay for satellite systems than the
conventional terrestrial systems.
33
By Biruk.P (MSc)

34. Determining if an organization is at risk
• Organizational risk is anything that generates uncertainty within an
enterprise. Business leaders concern themselves with organizational
risk because it has a direct impact on the financial stability of their
business.
• Product launch: Launching a new product often requires a great deal
of time and money and introduces risk in a business because you
don't know whether the product will be successful.
• Communication: When a business relies on a third-party system for
communication, they're entrusting an essential element of their
business to another company.
• Cybersecurity: Organizations experience risk whenever they connect
to the internet, which can put an organization's essential data at risk.
• Brand fatigue: Organizations commonly track customer engagement
metrics to ensure they're interacting with their audience at an
appropriate frequency, mitigating the risk of brand fatigue.
• Regulation compliance: Failure to meet government regulations
could mean fines, lawsuits or damage to the business's reputation.
• Natural disasters: Many businesses are at risk of being harmed by a
natural disaster such as a hurricane damaging a building or
earthquake disrupting the supply chain.
34
By Biruk.P (MSc)

35. power protection
• Power system protection is a branch of
electrical power engineering that deals with the
protection of electrical power systems
from faults[citation needed] through the disconnection of
faulted parts from the rest of the electrical network.
The objective of a protection scheme is to keep the
power system stable by isolating only the
components that are under fault, whilst leaving as
much of the network as possible in operation. The
devices that are used to protect the power systems
from faults are called protection devices.
35
By Biruk.P (MSc)

36. Cont…
Protection systems usually comprise five components
• Current and voltage transformers to step down the
high voltages and currents of the electrical power
system to convenient levels for the relays to deal with
• Protective relays to sense the fault and initiate a trip,
or disconnection, order
• Circuit breakers or RCDs to open/close the system
based on relay and autorecloser commands
• Batteries to provide power in case of power
disconnection in the system
• Communication channels to allow analysis of current
and voltage at remote terminals of a line and to allow
remote tripping of equipment.
36
By Biruk.P (MSc)

37. Computer Virus
• A computer virus is a program or piece of code designed to
damage your computer by corrupting system files, wasting
resources, destroying data or otherwise being a nuisance.
• Virus are unique from other forms of malware in that they are
self-replicating — capable of copying themselves across files
or other computers without a user's consent.
Common Computer Virus
 ware (mal-icious soft-ware). Here are some of the other,
most common kinds:
 Trojans: like the ancient wooden horse full of attackers it
takes its name from, this malware pretends to be harmless
legitimate software, or comes embedded in it, in order to trick
the user and open up the gates for other malware to infect a
PC.
37
By Biruk.P (MSc)

38. Cont…
 Spyware: with examples such as keyloggers, this kind of
malware is designed to spy on users, save their passwords,
credit card details, other personal data and online behavior
patterns, and send them off to whoever programmed it.
 Worms: this malware type targets entire networks of devices,
hopping from PC to PC.
 Ransomware: this malware variety hijacks files (and
sometimes an entire hard drive), encrypts them, and
demands money from its victim in exchange for a decryption
key (which may or may not work, but it probably won’t).
 Adware: this exceedingly irritating kind of malware floods
victims with unwanted ads, and opens up vulnerable security
spots for other malware to wiggle its way in.
38
By Biruk.P (MSc)

39. Security Programs
• Security software is designed to protect and secure
servers, laptops, mobile devices, and networks from
unauthorized access, intrusions, viruses, and other
threats. Security software can help defend data,
users, systems, and companies from a wide range of
risks.
Why is security software important?
Security software can improve both business and
information security. Operating without security
software--or using outdated solutions--leaves
organizations and users exposed to a wide range of
threats, including malicious hackers, spyware, viruses,
and malware.
39
By Biruk.P (MSc)

40. Data Recovery
• Data recovery is the process of restoring data that
has been lost, accidentally deleted, corrupted or
made inaccessible.
• Data recovery typically refers to the restoration of
data to a desktop, laptop, server or
external storage system from a backup
Causes of data loss
 Most data loss is caused by human error, rather
than malicious attacks
 Other common causes of data loss include power
outages, natural disasters, equipment failures or
malfunctions, accidental deletion of data,
unintentionally formatting a hard drive, damaged
hard drive read/write heads
40
By Biruk.P (MSc)

41. How data recovery works ?
• The data recovery process varies, depending on
the circumstances of the data loss, the data
recovery software used to create the backup and
the backup target media.
• Data recovery services can also be used to
retrieve files that were not backed up and
accidentally deleted from a computer's file
system, but still remain on the hard disk in
fragments.
41
By Biruk.P (MSc)

42. Physical Security
• Physical security describes security measures
that are designed to deny unauthorized access to
facilities, equipment, and resources and to protect
personnel and property from damage or harm
(such as espionage, theft, or terrorist attacks).
• Physical security measures are designed to
protect buildings, and safeguard the equipment
inside.
42
By Biruk.P (MSc)

43. End
43
By Biruk.P (MSc)