Transcript Technology In Action

 The
Final Exam
• Exam Questions
 Review
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Lab Exercises 5/6 and 7
Technology in Focus 5
Sound-bytes 11 to 13
Chapters 11 to 13
 Please
see the midterm study guides for
the covered topics from chapter 1 to 10
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When
• Tuesday, May 6, 2008
• 5:45 – 8:00pm
• MSB 115
25 % of your final grade
Covers
• Chapters 1 to 13
• Sound-bytes 1 to 13
• Technology in Focuses 1 to 5
• Lab exercises 1 to 7
This is an open-notes exam. All in-class hand-outs are allowed.
Writing on your notes is ok!
You may not use a textbook, a computer, or any electronic device.
You may see questions from the midterm exams and quizzes again.
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 100
questions (25% of the total grade)
• 30 multiple-choice questions
• 30 true/false questions
• 40 matching question
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Lab exercise 5/6
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Creating basic presentation slides using Microsoft
PowerPoint software
Learn more about computing artifacts
Lab exercise 7
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Creating a small relational database using Microsoft
Access software
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Technology in Focus 5: The History of
Computers
 Data storage devices
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From punch cards to DVDs
 Personal computers
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From Altair 8800 to modern day PC
 DOS/MS-DOS Operating systems
 Software applications
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Collect data in Access 2007 by using email
A day in the life of a network technician
The history of the personal computers
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Chapter 11
Behind the Scenes:
Databases and Information Systems
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 Databases
and their uses
 Database components
 Types of databases
 Database management systems
 Relational databases
 Data warehouses and data marts
 Information systems
 Data mining
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 What
is a database and why is it beneficial to
use databases?
• Databases are electronic collections of related data
that help us organize data so that we can more easily
access and use it.
• By creating an organized structure for data, we hope
to make data more meaningful and therefore more
useful. In other words, we are attempting to turn data
into information.
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 What
components make up a database?
• The three main components of a database are
 Fields
 Records
 Tables
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What types of databases are there?
• Relational databases
 Organize data in a (two-dimensional) table
 Link tables to each other through their primary keys
 Relational databases excel in the storage of structured (analytical)
data.
• Object-oriented databases
 Stores data in objects
 more adept at handling unstructured data, including audio clips,
video clips, pictures, and extremely large documents
• Multidimensional databases
 Stores data in multiple dimensions
 Can easily be customized for a variety of users
 Process data much faster than pure relational database
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 What
do database management systems do?
• DBMSs are specially designed application software
(such as MS Access) that interacts with the user,
other applications, and database itself to capture and
analyze data
• Four main operations of a DBMS are:
1.Creating databases and entering data
2.Viewing and sorting data
3.Extracting data
4.Outputting data
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How do relational databases organize and manipulate
data?
• Relational databases operate by organizing data into various
tables based on logical groupings.
• In relational databases, the links between tables that define
how the data is related are referred to as relationships.
• To establish a relationship between two tables, both tables must
have a common field (or column).
• In databases, the goal is to reduce data redundancy by
recording data only once. This process is called normalization
of the data.
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What are data warehouses and data marts and how are
they used?
• A data warehouse is a large-scale electronic repository of data
that contains and organizes in one place all the data related to
an organization. Individual databases contain a wealth of
information, but each database’s information usually pertains to
one topic.
• Data warehouses consolidate information from disparate
sources to present an enterprise-wide view of business
operations.
• Data in the data warehouse is organized by subject. Most
databases focus on one specific operational aspect of business
operations.
• Data marts are small slices of the data warehouse.
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What is an information system and what types of information systems
are used in business?
• Information systems are software-based solutions used to gather and
analyze information. Databases, data marts, and data warehouses are
integral parts of information systems because they store the information
that makes information systems functional.
• All information systems perform similar functions, including
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acquiring data
processing that data into information
storing the data, and
providing the user with output options with which to make the information
meaningful and useful.
• Most information systems fall into one of four categories:
 office support systems,
 transaction processing systems,
 management information systems, and
 decision support systems.
• Each type of system almost always involves the use of one or more
databases.
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 What
is data mining and how does it
work?
• Data mining is the process by which great
amounts of data are analyzed and investigated.
The objective is to spot significant patterns or
trends within the data that would otherwise not
be obvious.
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Chapter 12
Behind the Scenes:
Networking and Security
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Advantages of business networks
Client/server vs. peer-to-peer networks
Classifications of client/server networks
Client/server network components
Types of servers
Network topologies
Types of transmission media
Network software
Network adapters
Moving data in a client/server network
Securing networks
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What are the advantages of a business network?
• Large business networks provide the following advantages:
 They increase productivity. Networks allow workers to share data and
peripherals with coworkers and communicate with them efficiently.
 They enable people to share peripherals such as printers.
 They enable software sharing. Installing a new version of software on
everyone’s desktop in a company with 1,000 employees can be timeconsuming. However, if the computers are networked, all employees can
access the same copy of a program from the server. Although companies
must still purchase a software license for each employee, with a network
they avoid having to install the program on every desktop.
 Through a network, large groups of employees can share one Internet
connection, reducing Internet connectivity expenses.
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How does a client/server network differ from a peer-topeer network?
• The main advantage of a client/server relationship is that it
makes data flow more efficiently than in peer-to-peer networks.
Servers can respond to requests from a large number of clients at
the same time.
• Also, servers are configured to perform specific tasks (such as
handling e-mail or database requests) efficiently.
• Client/server networks are also scalable networks, meaning
additional users can be added easily without affecting the
performance of the other network nodes.
• In addition, whereas P2P networks are decentralized (users are
responsible for creating their own data backups and for
providing security for their computer), client/server networks
are centralized, meaning all clients connect to a server that
performs tasks for them.
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What are the different classifications of client/server
networks?
• Local area networks (LANs) are generally smaller groups of
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computers and peripherals linked together over a relatively small
geographic area.
Wide area networks (WANs) comprise large numbers of users or
separate LANs that are miles apart and linked together.
Metropolitan area networks (MANs) are established WANs to link
users in a specific geographic area (such as within a city or
county).
Personal area networks (PANs) are used to connect wireless
devices (such as Bluetooth-enabled devices) in close proximity to
each other.
An intranet is a private corporate network that is used exclusively
by company employees to facilitate information sharing, database
access, group scheduling, videoconferencing, or other employee
collaboration.
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What components are needed to construct a client/server network?
• Server. Unlike P2P networks, client/server networks contain at least one
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computer that functions solely as a server.
Network topology. Because client/server networks are more complex than
P2P networks, the layout and structure of the network must be carefully
planned.
Transmission media. Transmission media (cable or wireless communications
technology) is needed based on the network topology. Client/server networks
use a wider variety of cable types than do simpler P2P networks.
Network operating system (NOS) software. All client/server networks
require network operating system (NOS) software, which is specialized
software that is installed on servers and client computers that enables the
network to function.
Network adapters. Network adapters (or network interface cards) are attached
or installed to each device on a client/server network. These adapters enable
the computer (or peripheral) to communicate with the network using a
common data communication language, or protocol.
Network navigation devices. Because of the complexity of a client/server
network, specialized network navigation devices (such as routers, hubs, and
switches) are needed to move data signals around the network.
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What do the various types of servers do?
• The number and types of servers on a client/server network
depend on the network’s size and workload.
• As more users are added to a network, dedicated servers are
used to fulfill one specific function (such as handling e-mail).
When dedicated servers are deployed, the main server then
becomes merely an authentication server and/or a file server.
• Authentication servers keep track of who is logging on to the
network and which services on the network are available to each
user. Authentication servers also act as overseers for the network.
They manage and coordinate the services provided by any other
dedicated servers located on the network.
• File servers store and manage files for network users. On
corporate networks, employees are provided with space on a file
server to store files they create.
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 What
are the various network topologies?
• Network topology refers to the physical or
logical arrangement of computers, transmission
media (cable), and other network components.
• The most common client/server network
topologies are bus, ring, and star.
• Combining multiple topologies into one network
is known as constructing a hybrid topology.
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 What
types of transmission media are used in
client/server networks?
• Transmission media comprises the routes data takes
to flow between devices on the network.
• For business networks, the three main cable types
that are used today are twisted pair, coaxial, and
fiber-optic. Wireless networks are another popular
option.
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 What
software needs to be running on
computers attached to a client/server network?
• Network operating system (NOS) needs to be
installed on each client computer and server
connected to the network to provide the services
necessary for them to communicate.
• Many modern operating systems (such as Windows
XP and Mac OS X) include NOS client software as
part of the basic installation.
• However, if your OS does not include NOS client
software, it must be installed on each client.
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 How
do network adapters enable computers to
participate in a client/server network?
• Network adapters perform three critical functions:
 They generate high-powered signals to enable network
transmissions.
 They are responsible for breaking the data down into packets
and preparing them for transmission across the network.
 They act as gatekeepers for information flowing to and from
the client computer.
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What devices assist in moving data around a client/server network?
• Repeaters are devices whose sole function is to amplify a signal and
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retransmit it. Repeaters are used to extend cable runs beyond the
maximum run length (over which a signal would degrade and be
unreadable).
Hubs are devices that also transmit signals. In addition, they have multiple
ports to which devices are connected.
A switch can be viewed as a “smart” hub. It makes decisions, based on
the MAC address of the data, as to where the data is to be sent. Therefore,
only the intended recipient of the data receives the signal as opposed to a
hub, which sends out data to all devices connected to it.
Bridges are devices that are used to send data between different collision
domains.
Routers are designed to send information between two networks. To
accomplish this, routers must look at higher-level network addresses
(such as IP addresses), not MAC addresses. When the router notices data
with an address that does not belong to a device on the network from
which it originated, it sends the data to another network to which it is
attached (or out onto the Internet).
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What measures are employed to keep large networks secure?
• To gain access to a typical client/server network, you have to enter a user
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ID and a password. This is a process known as authentication. However,
authentication can also be achieved through the use of biometric devices
and through possessed objects. Examples include identification badges,
magnetic key cards, and smart keys.
Each user has access privileges granted in accordance with his or her
requirements. In this way, all activity on the network can be tracked to a
particular user.
Beyond this, physical protection of key equipment is accomplished by
keeping servers in areas with highly limited access. These areas often
have biometric access protection or special access cards.
Biometrics identify users by a physical trait like fingerprints, retina scans,
or facial recognition. These devices can be fooled and research is leading
to newer biometric methods, but none are yet perfected.
To protect a network from outside connection vulnerability, firewalls are
installed that prevent unauthorized access into the network from ports into
the Internet.
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Chapter 13
Behind the Scenes:
The Internet: How It Works
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 Managing
the Internet
 Interaction between Internet components
 Internet data transmission and protocols
 IP addresses and domain names
 FTP and Telnet
 HTML and XLM
 How e-mail and instant messaging work and
how to keep them secure
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What data transmissions and protocols does the
Internet use?
• Although many protocols are available on the Internet, the main
suite of protocols used is TCP/IP.
• The suite is named after the original two protocols that were
developed for the Internet: the Transmission Control Protocol
(TCP) and the Internet Protocol (IP).
• TCP prepares data for transmission and provides for errorchecking and resending lost data.
• IP is responsible for sending the information from one
computer to another.
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How do the Internet’s
networking components
interact?
• To connect individual
computers or networks to
the Internet, home users
and businesses use Internet
service providers (ISPs).
ISPs are classified in a
hierarchy that consists of
three tiers: Tier 1, Tier 2,
and Tier 3.
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 Why
are IP addresses and domain names
important for Internet communications?
• Each computer, server, or device connected to the
Internet is required to have a unique number
identifying it, called an IP address.
• A domain name is simply a name that takes the place
of an IP address, making it easier for people to
remember. For example, google.com is a domain
name.
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What are FTP and Telnet and how do I use them?
• The File Transfer Protocol (FTP) enables users to share files that
reside on local computers with remote computers. If you’re
attempting to download files using FTP to your local computer,
the FTP client program first establishes a TCP session with the
remote computer.
• Telnet is both a protocol for connecting to a remote computer
and a TCP/IP service that runs on a remote computer to make it
accessible to other computers. Telnet enables you to take
control of a remote computer (the server) with your computer
(the client) and manipulate files and data on the server as if you
were sitting in front of that server.
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 What
are HTML and XML used for?
• A Web page is merely a text document that is
formatted using the Hypertext Markup Language
(HTML).
• The current version of HTML is called the Extensible
Hypertext Markup Language (XHTML). XHTML has
much more stringent rules than HTML regarding
tagging (for instance, all elements require an end
tag).
• Extensible Markup Language (XML) is a set of tools
you can use to create your own markup language. In
a sense, it is a more flexible version of
HTML/XHTML.
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How does e-mail work?
• E-mail uses a protocol first developed by Ray Tomlinson in 1971.
Using the @ symbol, e-mail addresses place a user at a Web
location. The protocol works in a client/server format where email is sent to a server and is forwarded to another server where
it is retrieved by the addressee.
• Just like other kinds of data that flow along the Internet, e-mail
has its own protocol. The Simple Mail Transfer Protocol (SMTP) is
responsible for sending e-mail along the Internet to its
destination.
• The Multipurpose Internet Mail Extensions (MIME) specification
was introduced in 1991 to simplify adding attachments to e-mail
messages. All e-mail client software now uses this protocol for
attaching files.
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