NETWORKS, TELECOMMUNICATIONS, AND WIRELESS COMPUTING

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24 Οκτ 2013 (πριν από 3 χρόνια και 5 μήνες)

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McGraw
-
Hill/Irwin

©2008 The McGraw
-
Hill Companies, All Rights Reserved

CHAPTER 7

NETWORKS,
TELECOMMUNICATIONS,
AND WIRELESS
COMPUTING


7
-
2

Chapter Seven Overview


SECTION 7.1


NETWORKS AND
TELECOMMUNICATIONS


Network Basics


Architecture


Topology


Protocols


Media


E
-
Business Networks



SECTION 7.2


WIRELESS COMPUTING


Wireless Fidelity


Business Drivers for Wireless Technologies


Advantages of Enterprise Mobility


The Future of Wireless

7
-
3

LEARNING OUTCOMES

1.
Compare LANs, WANs, and MANs

2.
List and describe the four components that
differentiate networks

3.
Compare the two types of network
architectures

4.
Explain topology and the different types
found in networks

5.
Describe TCP/IP along with its primary
purpose

6.
Identify the different media types found in
networks


7
-
4

NETWORK BASICS


Telecommunication system
-

enable the
transmission of data over public or private
networks



Network
-

a resource
-
sharing system
created by linking two or more computers
following an establishing standards or
protocols

7
-
5

NETWORK BASICS


The three types of networks include:


Local area network (LAN): One building, a
small group of buildings, office, or a home.



Metropolitan area network (MAN): Joins
LANS across campuses



Wide area network (WAN): Across the
country or around the world (Internet)

7
-
6

NETWORK BASICS

7
-
7

NETWORK BASICS


Networks are differentiated by the following:


Architecture
-

peer
-
to
-
peer, client/server


Topology
-

bus, star, ring, hybrid, wireless


Protocols
-

Ethernet, Transmission Control
Protocol/Internet Protocol (TCP/IP)


Media
-

coaxial, twisted
-
pair, fiber
-
optic

7
-
8

ARCHITECTURE


There are two primary types of
architectures


Peer
-
to
-
peer (P2P) network


Client/server network



http://www.youtube.com/watch?v=Ve7_4ot
-
Dzs


7
-
9

Peer
-
to
-
Peer Networks


Peer
-
to
-
peer (P2P)
network
-

any
network without a
central file server
and in which all
computers in the
network have
access to the public
files located on all
other workstations

7
-
10

Client/Server Networks


Client

-

a computer that is designed to
request information from a server


Server
-

a computer that is dedicated to
providing information in response to external
requests


Client/server network
-

model for applications
in which the bulk of the back
-
end processing
takes place on a server, while the front
-
end
processing is handled by the clients

7
-
11

TOPOLOGY


Network topology
-

refers to the
geometric arrangement of the actual
physical organization of the computers
and other network devices) in a network


Bus


Star


Ring


Hybrid


Wireless



7
-
12

TOPOLOGY

7
-
13

PROTOCOLS


Protocol
-

a standard that specifies the
format of data as well as the rules to be
followed during transmission (e.g.
language)


Interoperability
-

the capability of two or
more computer systems to share data and
resources, even though they are made by
different manufacturers

7
-
14

Open Source Interconnection Model (OSI)

7
-
15

Ethernet


Ethernet
-

a physical and data layer
technology for LAN networking

7
-
16

Transmission Control Protocol/
Internet Protocol


Transmission Control Protocol/Internet
Protocol (TCP/IP)
-

provides the technical
foundation for the public Internet as well as for
large numbers of private network



TCP/IP applications


File transfer protocol (FTP)


Simple mail transfer protocol (SMTP)


Hypertext transfer protocol (HTTP)


Simple network management Protocol (SNMP)


7
-
17

Voice over IP (VoIP)


Voice over IP (VoIP)
-

uses TCP/IP
technology to transmit voice calls over
long
-
distance telephone lines



Can you recall some companies that offer
VOIP?


7
-
18

MEDIA


Network transmission media
-

refers to
the various types of media used to carry
the signal between computers


Wire media (guided)


Wireless media (unguided)

7
-
19

Wire Media


Wire media
-

transmission material
manufactured so that signals will be
confined to a narrow path and will behave
predictably



Three most commonly used types include:

1.
Twisted
-
pair wiring

2.
Coaxial cable

3.
Fiber optic (or optical fiber)

7
-
20

Wire Media

7
-
21

Wireless Media


Wireless media
-

natural parts of the Earth’s
environment that can be used as physical paths to carry
electrical signals


Wireless fidelity (wi
-
fi)



a means of linking computers
using infrared or radio signals



Common examples of wireless devices include:


Cellular phones and pagers


Global positioning systems (GPS)


Cordless computer peripherals


Home
-
entertainment
-
system control boxes


Two
-
way radios


Satellite television


7
-
22

WIRELESS FIDELITY (WI
-
FI)


Disruptive wireless technologies


WiMax wireless broadband


Radio frequency identification tags (RFID)

7
-
23

The Value of Timely Information



Timeliness is an aspect of information that
depends on the situation


Real
-
time information



immediate, up
-
to
-
date information


Real
-
time system



provides real
-
time
information in response to query requests

7
-
24

BUSINESS DRIVERS FOR
WIRELESS TECHNOLOGIES


Mobile and wireless are often used
synonymously, but actually denote two
different technologies


Mobile technology
-

means the technology can
travel with the user, but it is not necessarily in
real
-
time


Wireless technology
-

gives users a live
(Internet) connection via satellite or radio
transmitters

7
-
25

BUSINESS DRIVERS FOR
WIRELESS TECHNOLOGIES


Drivers of wireless technology growth
include:


Universal access to information and
applications


The automation of business processes


User convenience, timeliness, and ability to
conduct business 24x7





7
-
26

Technology Adoption (US)

Forbes Magazine July 7th, 1997

7
-
27

BUSINESS DRIVERS FOR
WIRELESS TECHNOLOGIES


Wireless devices changing business
include:


Wireless local area network (wLAN)


Cellular phones and pagers


Cordless computer peripherals


Satellite television


WiMax wireless broadband


Security sensor

7
-
28

Bluetooth


Bluetooth



an
omnidirectional wireless
technology that provides
limited
-
range voice and
data transmission over the
unlicensed 2.4
-
GHz
frequency band, allowing
connections with a wide
variety of fixed and portable
devices that normally would
have to be cabled together

7
-
29

Radio Frequency Identification


Radio frequency identification (RFID)
-

use
active or passive tags in the form of chips or
smart labels that can store unique identifiers
and relay this information to electronic readers



RFID tag

-

contains a microchip and an
antenna, and typically work by transmitting a
serial number via radio waves to an electronic
reader, which confirms the identity of a person
or object bearing the tag

7
-
30

RFID

7
-
31

Satellite


Microwave transmitter


commonly used to
transmit network signals over great distances


7
-
32

Global Positioning System


Global positioning system (GPS)


a device
that determines current latitude, longitude,
speed, and direction of movement


Market for GPS services is at $5 billion with
expectations for the demand to double over the next
five years



Geographic information system (GIS)


designed to work with information that can be
shown on a map