EX7
1. A network attached storage (NAS) device is a server connected to a network with the sole
purpose of providing storage. Any user or device connected to the network can access
files on the NAS device. These devices often use a RAID configuration. In the past,
enterprises were the primary users of NAS. With the introduction of smaller, less
expensive NAS devices, however, some home and small business users opt to add up to 6
TB or more of hard disk storage space to their network with a NAS device.
2. Advantages of SAS over parallel SCSI include thinner, longer cables; reduced
interference; less expensive; support for many more connected devices at once; and faster
speeds. In addition to hard disks, SAS interfaces support connections to optical disc
drives, printers, scanners, digital cameras, and other devices.
3. A standard CD-ROM is called a single-session disc because manufacturers write all items
on the disc at one time. Multisession means you can write on part of the disc at one time
and another part at a later time. Many people use archive discs or Picture CDs to preserve
their photos. When you post and share photos online on a photo sharing community, you
can choose to save your collection of online photos on an archive disc. An archive disc
stores photos from an online photo center in the jpg file format, usually at a maximum
resolution of 7200 pixels per photo. A Kodak Picture CD is a single-session CD-ROM
that stores digital versions of film using a jpg file format at a lower resolution, typically
1024 x 1536 pixels.
4. Memory cards enable mobile users easily to transport digital photos, music, or files to and
from mobile devices and computers or other devices. Common types of flash memory
cards include CompactFlash (CF), Secure Digital (SD), Secure Digital High Capacity
(SDHC), microSD, microSDHC, xD Picture Card, Memory Stick, and Memory Stick
Micro (M2). CompactFlash cards have a storage capacity of 512 MB to 100 GB and are
used in digital cameras, smart phones, PDAs, photo printers, portable media players,
notebook computers, and desktop computers. Secure Digital cards have a storage capacity
of 512 MB to 8 GB and are used in digital cameras, digital video cameras, smart phones,
PDAs, photo printers, and portable media players. SDHC cards have a storage capacity of
4 to 32 GB and are used in digital cameras. microSD cards have a capacity of 1 to 2 GB
and are used in smart phones, portable media players, handheld game consoles, and
handheld navigation devices. MicroSDHC cards have a capacity of 4 to 16 GB and are
used in the same items as the microSD cards. xD Picture Cards have a storage capacity of
256 MB to 2 GB and are used in digital cameras and photo printers. Memory Stick PRO
Duo cards have a storage capacity of 1 to 16 GB and are used in digital cameras, smart
phones, and handheld game consoles. Memory Stick Micro (M2) cards have a capacity of
1 to 16 GB and are used in smart phones.
5. Microfilm is a 100- to 215-foot roll of film. Microfiche is a small sheet of film, usually
about 4 x 6 inches. Microfilm and microfiche use is widespread, with many companies
allowing you to search through and view microfilm images online. Libraries use these
media to store back issues of newspapers, magazines, and genealogy records. Some large
organizations use microfilm and microfiche to archive inactive files. Some banks use
them to store transactions and canceled checks. The U.S. Army uses them to store
personnel records.
EX8
1. A cold boot is performed when you turn on a computer that has been powered off
completely. A warm boot, by contrast, is the process of using the operating system to restart a
computer. A memory resident part of an operating system, such as the kernel, remains in
memory while the computer is running. A nonresident part of an operating system remains on
the hard disk until it is needed.
2. A user interface controls how you enter data and instructions and how information
displays on the screen. In a command-line interface, a user types commands or presses
special keys on the keyboard to enter data and instructions. With a graphical user interface
(GUI), you interact with menus and visual images such as icons, buttons, and other graphical
objects to issue commands.
3. Many popular programs, including most operating systems, include an automatic update
feature that automatically provides updates to the program. With an operating system, these
updates can include fixes to program bugs, or errors, enhancements to security, modifications
to device drivers, access to new or expanded components such as desktop themes or games,
and even updates to application software on the computer such as a Web browser or an e-mail
program. Many software makers provide free downloadable updates, sometimes called a
service pack, to users who have registered and/or activated their software. With operating
systems, the automatic update feature automatically alerts users when an update is available;
further, it can be configured to download and install the update automatically.
4. During the backup process, the backup utility monitors progress and alerts you if it
needs additional media, such as another disc. Many backup programs compress, or shrink the
size of, files during the backup process. By compressing the files, the backup program
requires less storage space for the backup files than for the original files. In the event you
need to use a backup file, a restore utility reverses the process and returns backed up files to
their original form. Backup utilities work with restore utilities.
5. Windows Embedded CE is a scaled-down Windows operating system designed for use
on communications, entertainment, and computing devices with limited functionality.
Windows Mobile, an operating system based on Windows Embedded CE, includes
functionality, programs, and a user interface designed for specific types of smart phones and
PDAs. A competing operating system to Windows Mobile is Palm OS, which runs on smart
phones and PDAs. With Palm OS devices, users manage schedules and contacts, phone
messages, notes, task and address lists, and appointments. iPhone OS, developed by Apple, is
an operating system for the iPhone and iPod touch, Apple’s smart phone and touch screen
portable media player, respectively. The BlackBerry operating system runs on handheld
devices supplied by RIM (Research In Motion). BlackBerry devices provide PIM capabilities
such as managing schedules, contacts, and appointments, as well as phone capabilities.
Embedded Linux is a scaled-down Linux operating system designed for smart phones, PDAs,
portable media players, Internet telephones, and many other types of devices and computers
requiring an embedded operating system. Symbian OS is an open source multitasking
operating system designed for smart phones. In addition to making phone calls, users of
Symbian OS can maintain contact lists; save appointments; browse the Web; and send and
receive text and picture messages, e-mail messages, and faxes using a smart phone.
EX9
1. A mobile device with text messaging, also called SMS (short message service),
capability allows users to send and receive short text messages on a phone or other mobile
device or computer. Text messaging services typically provide users with several options for
sending and receiving messages: • Mobile to Mobile: send a message from your mobile
device to another mobile device • Mobile to E-Mail: send a message from your mobile device
to an e-mail address anywhere in the world • Web to Mobile: send a message from a text
messaging Web site to a mobile device, or request that a Web site alert a mobile device with
messages of breaking news and other updates, such as sports scores, stock prices, and
weather forecasts • Mobile to Provider: send a message by entering a common short code
(CSC), which is a four- or five-digit number assigned to a specific content or wireless service
provider, followed by the message, such as a vote for a television program contestant or an
entry for a sweepstakes.
2. A global positioning system (GPS) is a navigation system that consists of one or more
earth-based receivers that accept and analyze signals sent by satellites in order to determine
the receiver’s geographic location. The first and most used application of GPS technology is
to assist people with determining where they are located. The data obtained from a GPS,
however, can be applied to a variety of other uses: creating a map, ascertaining the best route
between two points, locating a lost person or stolen object, monitoring the movement of a
person or object, determining altitude, and calculating speed. Many vehicles use GPSs to
provide drivers with directions or other information, such as alternate traffic routes,
automatically call for help if the airbag is deployed, dispatch roadside assistance, unlock the
driver’s side door if keys are locked in the car, and track the vehicle if it is stolen. Hikers and
remote campers may carry GPS receivers in case they need emergency help or directions.
Some GPS receivers work in conjunction with a cellular wireless network. Parents, for
example, can locate a child’s whereabouts through a cell phone equipped with a GPS
receiver.
3. A local area network (LAN) is a network that connects computers and devices in a
limited geographical area such as a home, school computer laboratory, office building, or
closely positioned group of buildings. A metropolitan area network (MAN) is a high-speed
network that connects local area networks in a metropolitan area such as a city or town and
handles the bulk of communications activity across that region. A wide area network (WAN)
is a network that covers a large geographic area (such as a city, country, or the world) using a
communications channel that combines many types of media. A wireless LAN (WLAN) is a
LAN that uses no physical wires.
4. A network topology refers to the layout of computers and devices in a communications
network. Five types of digital dedicated lines are ISDN lines, DSL, FTTP, T-carrier lines, and
ATM.
5.
Three types of digital modems are ISDN modems, DSL modems, and cable modems. An
ISDN modem sends digital data and information from a computer to an ISDN line and
receives digital data and information from an ISDN line. A DSL modem sends digital data
and information from a computer to a DSL line and receives digital data and information
from a DSL line. ISDN and DSL modems usually are external devices, in which one end
connects to the telephone line and the other end connects to a port on the system unit. A cable
modem, sometimes called a broadband modem, is a digital modem that sends and receives
digital data over the cable television (CATV) network.
EX11
1. An antivirus program scans for programs that attempt to modify the boot program, the
operating system, and other programs that normally are read from but not modified. In
addition, many antivirus programs automatically scan files downloaded from the Web, e-mail
attachments, opened files, and all types of removable media inserted in the computer. One
technique that antivirus programs use to identify a virus is to look for virus signatures. A
virus signature, also called a virus definition, is a known specific pattern of virus code. A
virus hoax is an e-mail message that warns users of a nonexistent virus or other malware.
2. The United States Department of Energy (DOE) and the United States Environmental
Protection Agency (EPA) developed the ENERGY STAR program to help reduce the amount
of electricity used by computers and related devices. This program encourages manufacturers
to create energy-efficient devices that require little power when they are not in use. For
example, many devices switch to sleep or power save mode after a specified number of
inactive minutes or hours. Computers and devices that meet the ENERGY STAR guidelines
display an ENERGY STAR label. Because of the huge volumes of electronic waste, the U.S.
federal government has proposed a bill that would require computer recycling across the
country. Many state and local governments have methods in place to make it easy for
consumers to recycle this type of equipment. Many computer manufacturers, office supply
stores, and other agencies offer free recycling to consumers and organizations.
3. Information privacy refers to the right of individuals and companies to deny or restrict
the collection and use of information about them. Five ways to protect your personal
information are: 1) Fill in only necessary information on rebate, warranty, and registration
forms. 2) Do not preprint your telephone number or Social Security number on personal
checks. 3) Have an unlisted or unpublished telephone number. 4) If Caller ID is available in
your area, find out how to block your number from displaying on the receiver’s system. 5) Do
not write your telephone number on charge or credit receipts. (Answers may vary. See Figure
11-31 on page 584.)
4. The two methods for avoiding phishing attacks are to first, never click a link in an
e-mail message; instead, retype the Web address in your browser. Second, use a phishing
filter. A phishing filter is a program that warns or blocks you from potentially fraudulent or
suspicious Web sites. Some Web browsers include phishing filters. To further help deter
spam and phishing scams, Microsoft and others are developing standards that require e-mail
messages contain sender identification so that recipients can verify the legitimacy of
messages. With clickjacking, an object that can be clicked on a Web site, such as a button,
image, or link, contains a malicious program. When a user clicks the disguised object, a
variety of nefarious events may occur. For example, the user may be redirected to a phony
Web site that requests personal information, or a virus may download to the computer.
5.
Many businesses use content filtering to limit employees’ Web access. These businesses
argue that employees are unproductive when visiting inappropriate or objectionable Web
sites. Some schools, libraries, and parents use content filtering to restrict access to minors.
Major Web sites such as Yahoo!, AOL, and MSN use the rating system established by the
ICRA. If content at the Web site goes beyond the rating limits set in the Web browser
software, a user cannot access the Web site. Concerned parents can set the rating limits and
prevent these limits from being changed by using a password.
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