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1. Compare LANs, WANs, and MANs




A local area network (LAN) is designed to connect group of computers in
close proximity to each other such as in an office building, a school, or a
home.




A wide area network (WAN) spans a large geographic area, such as a
state, province or country. WANs often connect multiple smaller networks,
such as local area networks (LANs) or metropolitan area networks
(MANs).



A metropolitan area network (MAN) is a l
arge computer networks usually
spanning a city.

2. List and describe the four components that differentiate networks




Networks are differentiated by the following:



Architecture

peer
-
to
-
peer, client/server



Topology

bus, star, ring, hybrid, wireless



Protocol
s

Ethernet, Transmission Control Protocol



Media

coaxial, twisted
-
pair, fiber
-
optic

3. Compare the two types of network architectures




A peer
-
to
-
peer (P2P) network is any network without a central file server
and in which all computers in the network have a
ccess to the public files
located on all other workstations. A client is a computer that is designed to
request information from a server. A server is a computer that is dedicated
to providing information in response to external requests. A client/server

network is a model for applications in which the bulk of the back
-
end
processing, such as performing a physical search of a database, takes
place on a server, while the front
-
end processing, which involves
communicating with the users, is handled by the c
lients


4. Explain topology and the different types found in networks




Network topology refers to the geometric arrangement of the actual
physical organization of the computers and other network devices) in a
network. The five common types found in networ
ks include:



Bus

-

All devices are connected to a central cable, called the bus or
backbone. Bus networks are relatively inexpensive and easy to install for
small networks.



Star

-

All devices are connected to a central device, called a hub. Star
networks ar
e relatively easy to install and manage, but bottlenecks can
occur because all data must pass through the hub.



Ring

-

All devices are connected to one another in the shape of a closed
loop, so that each device is connected directly to two other devices, on
e
on either side of it. Ring topologies are relatively expensive and difficult to
install, but they offer high bandwidth and can span large distances.



Hybrid

-

Groups of star
-
configured workstations are connected to a linear
bus backbone cable, combining
the characteristics of the bus and star
topologies.



Wireless

-

Devices are connected by a receiver/transmitter to a special
network interface card that transmits signals between a computer and a
server, all within an acceptable transmission range.

5. Descr
ibe TCP/IP along with its primary purpose




Transmission Control Protocol/Internet Protocol (TCP/IP) provides the
technical foundation for the public Internet as well as for large numbers of
private networks.


6. Identify the different media types found in
networks.




Wire media are transmission material manufactured so that signals will be
confined to a narrow path and will behave predictably. The three most
commonly used types of guided media are



Twisted
-
pair wiring



Coaxial cable



Fiber
-
optic cable



Wireless

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

7. Describe the business benefits associated with VoIP.


VoIP uses existing network and Internet infrastructure to route telephone calls mor
e
efficiently and inexpensively than traditional telephone service, VoIP offers businesses
significant cost savings, productivity gains and service enhancements.

8. Explain the difference between a VPN and a VAN.


A virtual private network (VPN) is a way
to use the public telecommunication
infrastructure (e.g., Internet) to provide secure access to an organization’s network. A
valued
-
added network (VAN) is a private network, provided by a third party, for
exchanging information through a high
-
capacity conn
ection.

9. Identify the advantages and disadvantages of broadband technology.



Digital Subscriber Line(DSL): Good upload rates, Uses existing telephone lines,
Speeds vary depending on distance from telephone company's central office,
Slower downloads than
less expensive alternatives



Cable: Uses existing cable infrastructure, Low
-
cost equipment, Shared
connections can overload system, slowing upload times



TI/T3 Dedicated Line: Uses existing phone wiring, Performance drops
significantly with range, Susceptibl
e to crosstalk



Fiber
-
to
-
the
-
Home(FTTH): Fast data speeds, Infrastructure has long life
expectancy, Low maintenance, Low power costs, Not widely available,
Significant deployment cost (for company)



Fixed Wireless: Typically inexpensive to install, no underg
round digging,
Weather, topography, buildings, and electronics can cause interference



Satellite: Nearly universal coverage, Available in otherwise inaccessible areas,
Expensive service/equipment, Upload/download delays

10. List and describe many of the net
work security problems.



An organization has to be concerned about proper identification of users and
authorization of network access, the control of access, and the protection of data
integrity. Almost all networks require some kind of logon, including u
ser name and
password. Many people are casual with their passwords, making them easy to guess. A
good password has both letters and numbers along with a few punctuation marks for
added security. Most corporate security goes far beyond passwords such as usi
ng a
"firewall," a computer that sits between an internal network and the Internet. The firewall
allows access to internal data from specified incoming sites but tries to detect
unauthorized access attempts and prevent them from occurring.



Telecommunicatio
n system
-

enable the transmission of data over public or
private networks



Network
-

a communications, data exchange, and resource
-
sharing system
created by linking two or more computers and establishing standards, or
protocols, so that they can work
together



The three types of networks include:



Local area network (LAN)



Metropolitan area network (MAN)



Wide area network (WAN)



Local area network (LAN)
A computer network that uses cables or radio signals
to link two or more computers within a
geographically limited area, generally one
building or a group of buildings. A networked office building, school, or home
usually contains a single LAN. The linked computers are called workstations.




Wide area network (WAN)
A computer network that provides

data
communication services for business in geographically dispersed areas (such as
across a country or around the world). The Internet is a WAN that spans the
world.




Metropolitan area network (MAN)
A computer network that provides
connectivity in a geog
raphic area or region larger than that covered by a local
area network, but smaller than the area covered by a wide area network. A
college or business may have a MAN that joins the different LANs across its
campus.



There are two primary types of architect
ures



Peer
-
to
-
peer (P2P) network



Client/server network



What is the primary difference between these two types of architectures?



The server



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



BitTorrent is an excellent example of peer
-
to
-
peer




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



Network operating system (NOS)
-

the operating system that runs a network,
steering information between computers and managing security and users



Packet
-
switching
-

occurs when the sending computer divides a message into a
number of efficiently sized units called packets, each of which
contains the
address of the destination computer



Router
-

an intelligent connecting device that examines each packet of data it
receives and then decides which way to send it onward toward its destination



Network topology
-

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



Bus



Star



Ring



Hybrid



Wireless



Bus
-

All devices are connected to a central cable, called the bus or backbone.
Bus networks are relatively inexpensive and easy
to install for small networks




Star
-

All devices are connected to a central device, called a hub. Star networks
are relatively easy to install and manage, but bottlenecks can occur because all
data must pass through the hub




Ring
-

All devices are connect
ed to one another in the shape of a closed loop, so
that each device is connected directly to two other devices, one on either side of
it. Ring topologies are relatively expensive and difficult to install, but they offer
high bandwidth and can span large d
istances




Hybrid
-

Groups of star
-
configured workstations are connected to a linear bus
backbone cable, combining the characteristics of the bus and star topologies




Wireless
-

Devices are connected by a receiver/transmitter to a special network
interface
card that transmits signals between a computer and a server, all within
an acceptable transmission range



Protocol
-

a standard that specifies the format of data as well as the rules to be
followed during transmission



Interoperability
-

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



Ethernet
-

a physical and data layer technology for LAN networking



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)



File Transfer Protocol (FTP)
Allows files containing text, programs, graphics,
numerical data, and so on to be downloaded off or uploaded onto a network.




Simple Mail Transfer Protocol (SMTP)
TCP/IP’s own messaging system for e
-
mail.




Telnet Protocol
Provi
des terminal emulation that allows a personal computer or
workstation to act as a terminal, or access device, for a server.




Hypertext Transfer Protocol (HTTP)
Allows Web browsers and servers to send
and receive Web pages.




Simple Network Management Protoc
ol (SNMP)
Allows the management of
networked nodes to be managed from a single point



Network transmission media
-

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



Wire media (guided)



Wireless media (unguided)



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:



Twisted
-
pair wiring



Coaxial cable



Fiber optic (or optical fiber)



Wire media
are transmission materia
l manufactured so that signals will be
confined to a narrow path and will behave predictably. The three most commonly
used types of guided media are



Twisted
-
pair wiring



Coaxial cable



Fiber
-
optic cable




Twisted
-
pair wiring
-

refers to a type of cable compo
sed of four (or more)
copper wires twisted around each other within a plastic sheath




Coaxial cable


carries

a wide range of frequencies with low signal loss




Fiber optic
(or
optical fiber
)
-

refers to the technology associated with the
transmission of in
formation as light impulses along a glass wire or fiber



Wireless media
-

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



Virtual private network (VPN)
-

a way to use the publi
c telecommunication
infrastructure (e.g., Internet) to provide secure access to an organization’s
network



Valued
-
added network (VAN)
-

a private network, provided by a third party, for
exchanging information through a high capacity connection



Voice over IP (VoIP)
-

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



Prada recently spent millions on technology for its futuristic “epicenter” store
-

but
the flashy technology turned into a high
-
priced hassle



Fickle fi
tting rooms

Doors that turn from clear to opaque confuse
shoppers and frequently fail to open on cue



Failed RFID

Touch screens meant to spring to life when items are
placed in the RFID “closets” are often just blank



Pointless PDAs

Salesclerks let the handh
eld devices gather dust and
instead check the stockroom for inventory



Neglected network

A lag between sales and inventory systems makes
the wireless network nearly irrelevant

1. Explain how Prada was anticipating using its wireless network to help its sto
re
operate more efficiently. What prevented the system from working correctly?




Prada’s use of RFID is disruptive for the fashion industry. Using RFID to
track inventory is not disruptive in the manufacturing industry or production
industry, but it is a
radical change from most specialty stores.

2. What could Prada have done to help its employees embrace the wireless
network?




Prada could have implemented in phases and tested to ensure that the
system worked and that the employees knew how to use it. B
y only
having one or two employees learn the new system for a few items, they
could have ensured that it worked and not overwhelmed the employees
with the new technology. Employees were frequently overwhelmed with
the number of customers they had to serve

and found it easier to manually
check inventory. If they were properly trained on the new system, they
would have found that it was easier to check a hand
-
held device than to
walk back and manually check inventory.


3. Would Prada have experienced the sa
me issues if it had used a wire (guided)
network instead of a wireless (unquided) network?




Implementing the technology in phases or pieces would have helped
Prada gain success with its high
-
tech dressing rooms. Prada could have
installed one high
-
tech dr
essing room and determined if customers were
satisfied, if they understood how to use it, and if they liked or enjoyed
them. Prada also could have installed the foot pedal first and got people
accustomed to the technology of the windows and then installed

the
wireless inventory tracking screens. Again, small incremental steps would
have been the best way for Prada to build a successful high
-
tech store.


4. What security issues would Prada need to be aware of concerning its wireless
network?




IT infrastruc
ture, security, e
-
business, and integration are the four primary
information technology areas where organizations are focusing in the 21st
century. If Prada wants to gain a competitive advantage, and remain
competitive, it should continue to seek out new
ways of using technology
to disrupt its market. Prada was on the right path when building its high
-
tech stores, it just used the wrong development methodology and
implementation methods.


5. What should Prada do differently when designing its fourth store

to ensure its
success?




Use an agile methodology to implement the new technology in small
manageable pieces, which will allow the employees and the customers
time to get used to each piece before learning a new piece.




Bank of America, Commerce Bancorp,
PNC Financial Services Group, and
Wachovia were victims of a crime involving a person trying to obtain customer
data and sell it to law firms and debt
-
collection agencies



In the past, banks were wary of the cost or customer backlash from adopting
network s
ecurity technologies



Today, banks are beefing up network security as more customers begin to view
security as a key factor when choosing a bank


1. What reason would a bank have for not wanting to adopt an online
-
transfer
delay policy?




Operating in a 24x7

world means instant gratification for many people.
Barclay’s online
-
transfer delay provides additional security, but losses
real
-
time response, which many people expect when dealing with the
Internet. A bank may choose not to implement an online
-
transfer
delay if
its customers view speed and efficiency a key factor.

2. What are the two primary lines of security defense and why are they important
to financial institutions?




The two primary lines of security defense are people and technology.
Since banks de
al with money they must offer the most advanced security
features to keep their customers finances safe. According to Figure 4.17,
the financial industry has the fifth highest expenditure/investment per
employee for computer security. An unsafe bank will n
ot operate long.

3. Explain the difference between the types of security offered by the banks in the
case. Which bank would you open an account with and why?




Bank of America is implementing authentication and authorization
technologies such as online com
puter identification



Wells Fargo & Company is implementing authentication and authorization
technologies such as additional password criteria



E
-
Trade Financial Corporation is implementing authentication and
authorization technologies such as Digital
Security IDs



Barclay’s Bank is implementing prevention technologies such as online
-
transfer delays and account monitoring

4. What additional types of security, not mentioned in the case above, would you
recommend a bank implement?




Banks need to implement

security technologies for all three primary areas
including:



Authentication and authorization
-

something the user knows such as a
user ID and password, something the user has such as a smart card or
token, something that is part of the user such as fing
erprint or voice
signature



Prevention and resistance
-

content filtering, encryption, firewalls



Detection and response


antivirus software



Providing a combination of all three types is optimal


5. Identify three policies a bank should implement to help
it improve information
security?




Information security plans detail how the organization will implement the
information security policies. Information security policies identify the
rules required to maintain information security. Banks must implement
inf
ormation security plans that focus on the following:



Identification and assessment of risks to customer information, ensure the
security and confidentiality of protected information, protect against
unauthorized access to or use of protected information th
at could result in
substantial harm or inconvenience to any customer, interception of data
during transmission, loss of data integrity, physical loss of data in a
disaster, errors introduced into the system, corruption of data or systems,
unauthorized acce
ss of data and information, unauthorized transfer of
data to third parties