Pairwork: Student B
UNIT 2
• Portable • High Performance 256-bit Options
• Mobile Pentium III Processor 32MB Graphics • Upgrade to 256MB RAM
850MHz • 15" SXGA (1400 x 1050) High • 56Kbps PCMCIA Modem
• 100 MHz system bus Resolution TFT Display • 3 Year International Next-
• 20GB EIDE Hard Disk • Microsoft Windows 2000 business-day on-site service
• 128MB SDRAM • Spare lithium ion battery
• Modular 16/40X DVD Drive • 10/100 Ethernet Port
and 3.5" Floppy Drive Replicator
2 The transaction data
travel by satellite or
Portland, OR ground to a processing
1 In Chicago, a VISA card is used center in New Jersey.
to pay for a $ 1,295 computer.
The California computer finds
that the card was issued by a
Portland bank and checks
that bank's computer system
to see if the transaction Total transaction time
request should be approved is about 15 seconds
or denied.
Because the transaction tops $50, it
is routed to a computer in Atlanta
for closer scrutiny.The computer in
Atlanta sends the transaction to
Fig 4 Visa cards California for processing.
UNIT6
PC-DOS An operating system similar to MS-DOS that Windows 9X The operating system that replaced MS-
has been widely used on IBM microcomputers. DOS and Windows 3.1, combining the functionality of
Unix An operating system used on all sizes of both programs and much more into a single package;
computers, but mostly large ones; available in many two versions were produced, Windows 95 and
versions, such as Linux, HP-UX, Xenix, Venix, Ultrix, Windows 98, although various editions were made
A/UX, AIX, Solaris, and PowerOpen. available.
VAX/VMS An operating system used by DEC VAX Windows 2000 An operating system targeted
minicomputers. primarily to corporate client-server applications;
Windows 3.x* Refers to the Windows 3.0 and available in both a desktop version and a version for
Windows 3.1 operating environments, and to variants network administration.
such as Windows for Workgroups 3.11; each of these is
a graphically-oriented shell program for Microsoft's
MS-DOS operating system. *Not a full operating system
UNIT 8
r e v i e w s
Sim City 3000: World edition
PC Maxis/Electronic Arts
The basic game is the same as quickly flip them into a If you gave up on SC2000,
it was when it first appeared European (German) or Asian this will restore your faith; and
on the Commodore 64: zone (Korean/Japanese) style. You if you haven't played Sim City
land, build roads, set taxes and can add landmarks such as the before, this is a good place to
let simulated citizens build the Brandenburg Gate and the start.
city of your dreams or Eiffel Tower.
Jack Schofield
nightmares. A huge amount of
The amount of detail in the
detail has been added since
3D buildings, cars and
then, and the World edition
pedestrians is stunning. A new
integrates hundreds of new
website is introduced also
buildings, a building editor, a
(www.simcity.com). There you
terrain editor, and a scenario
can download even more
editor.
buildings and swap files,
You no longer have to build buildings, city photos and
American cities, and you can scenarios with fellow fans.
UNIT9 Explain to your partner with the help of these notes what MPEG
Video is and how it operates.
MPEG = method of compressing/decompressing video
signals to reduce size by up to 95%
video sequences stored in series or frames
intraframe (l-frame) every 1/3rd second has most important
picture information
between l-frames are predicted frames (P-frames) and
bidirectional frames (B-frames)
P- and B-frames store changes only
P- and B-frames preserve video quality between l-frames
Human eye can't detect information discarded
192 PAIRWORK Student B
U N I T 11
Synchronous transmission sends data in blocks of been correctly transmitted.
characters. Start and stop bit patterns, called synch This method is rarely used with microcomputers
bytes, are transmitted at the beginning and end of the because it is more complicated and expensive than
blocks. These start and end bit patterns synchronise asynchronous transmission. It also requires careful
internal clocks in the sending and receiving devices so timing between sending and receiving equipment. It is
that they are in time with each other. Error check bytes appropriate for computer systems that need to
are included immediately after each block of characters transmit great quantities of data quickly.
to ensure that the whole sequence of characters has
UNIT 14
Product overview (product.htm) Order form (order.htm) page where
Some general information visitors can order on-line
'Paula's Plants':
Website overview Fig 1b Site diagram
UNIT 15 Problems
You would like to cheer up a friend.
You're going to rent a car in the USA and travel from Miami to
New Orleans. You would like to plan a route.
You're going walking in the mountains this weekend. You would
like to know what the chances are of rain.
You want to forward a video email attachment you've received to
a friend and it won't go.
Travel Research Neon City Exercise information
Whether you're looking for the If you have a webpage that's If your current exercise
best airline and hotel fares or looking a little dull, you might program doesn't seem to be
researching the best travel want to add some neon signs, working, consult the Web.
destinations, the Web can help. words or tubes. Neon City While Web surfing doesn't
Several websites also offer tips produces a variety of cool neon qualify as exercise, you can use
for travelling by aeroplane or clipart that you are free to use the Web to find information on
with small children. Some allow on your personal webpage so an exercise program you'll
you to book train tickets. long as you link to the page you enjoy. Some websites also help
www.expedia.com got the design from. to track your progress.
www.concierge.com www.neoncity.co.uk www.fitnesslink.com
www.thetrainline.co.uk www.runnersworld.com
PAIRWORK Student B 193
UNIT 16 Communication Systems
Text and Graphics only Multimedia
Synchronous Asynchronous Synchronous
fax Netphones Webpages
newsgroup
Fig 2b World of connectivity
UNIT 17 Problem B
The monitor display screen is flickering.
SYSTEM
Make and model
INSTRUCTIONS RESULT
Compaq, CV602
Change the monitor refresh rate setting by: Monitor no
Service Number
• Right clicking with the mouse on the desktop longer flickering.
8JD3
• Selecting 'Properties-Settings'
Processor • Clicking on the Advanced button
Pentium III • Choosing the 'Monitor' tab.
Memory • Making sure that the 'Hide modes that this monitor cannot display'
128MB checkbox is ticked.
O.S. • Selecting a higher refresh rate (i.e. 75Hz or more).
Windows 2000 • Rebooting the computer.
• Checking that the monitor is functioning properly.
Configuration
Windows 2000
network
Stealing by stealth
UNIT 18 Anti-virus detection
How a Trojan may have penetrated program doesn't detect the
Microsoft's defences Trojan, allowing it through
the firewall.
ANTIVIRUS
Hacker writes script and hides PROGRAM
script in other code e.g. image
file, game or utility and Microsoft employee opens
attaches hidden script (Trojan) attachment, thereby
to email. Sends email to activating the Trojan code.
someone at Microsoft.
Names and passwords are
used by hacker to cruise
Script uses a Microsoft Microsoft network for Virus program
email program to send source code software. records
names and passwords names and
to hacker. passwords.
Fig 3 Stealing by stealth
194 PAIRWORK Student B
UNIT 19
A differential backup doesn't set the archive bit to the off
position after backing up the file. In a full backup in
Windows, the operating system automatically sets the
archive bit to 0 (off). 1 (on) indicates a file has not been
backed up since it was last worked on. Thus, if you do a
series of differentials, each backs up all the files created or
modified since the last full backup, not just those that have
changed. Normally, you keep only the most recent
differential backup on hand. This minimises the size of your
backup set, since it will never contain more than two copies
of any file — one in the full set and one in the differential.
This method is mostly used when you're backing up to
disks. The downside is that it won't back up files that were
created and deleted before the differential backup.
UNIT 21 XML Stands for extensible Markup Language; XML is a
metalanguage for creating webpages with meaningful data
that can be used by a variety of programs.
C++ C++ is an object-oriented superset of C which combines the
best features of a structured high-level language and an
assembly language - that is, it's relatively easy to code and
uses computer resources efficiently. C was originally designed
to write systems software but is now considered a general-
purpose language.
Visual Basic BASIC stands for Beginners' All-purpose Symbolic Instruction
Code; Visual Basic is a simple-to-use language that has a
graphical interface. It makes it particularly easy for an
inexperienced programmer to create database programs.
Pascal Pascal, named after the mathematician Blaise Pascal, was
created primarily to fill the need for a teaching vehicle that
would encourage structured programming. It is often used in
college computing courses.
COBOL Stands for COmmon Business-Oriented Language; it has been
around for a long number of years but is still an important
transaction-processing language used to process the records of
large organisations on mainframe computers.
PAIRWORK Student B 195
U N I T 22
1 Computer Salesperson
Advises potential customers about available hardware and sells
equipment to suit individual requirements. Discusses computing needs
with the client to ensure that a suitable system can be supplied.
Organises the sale and delivery and, if necessary, installation and
testing. May arrange support or training, maintenance and consultation.
Must have sufficient technical knowledge.
2 Applications Programmer
Writes the programs which enable a computer to carry out particular
tasks. May write new programs or adapt existing programs, perhaps
altering computer packages to meet the needs of an individual company.
When writing a new program, follows a specification provided by a
systems analyst. Devises a series of logical steps and converts these to
the appropriate computer language. Checks programs for faults and
does extensive testing.
3 Systems Support Person
Systems support people are analyst programmers who are responsible
for maintaining, updating and modifying the software used by a
company. Some specialise in software which handles the basic operation
of the computers. This involves use of machine codes and specialised
low-level computer languages. Most handle applications software. May
sort out problems encountered by users. Solving problems may involve
amending an area of code in the software, retrieving files and data lost
when a system crashes and a basic knowledge of hardware.
4 Hardware Engineer
Researches, designs and develops computers, or parts of computers and
the computerised element of appliances, machines and vehicles. Also
involved in their manufacture, installation and testing. May specialise in
different areas: research and development, design, manufacturing. Has
to be aware of cost, efficiency, safety and environmental factors as well
as engineering aspects.
