ICDL Module 1 (IT) lec (4)

Security
1.7.I Information Security
1.7.1.1 Understand the term information security and the benefits to an
organisation of being proactive in dealing with security risks such as:
adopting an information security policy with respect to handling
sensitive data, having procedures for reporting security incidents,
making staff members aware of their responsibilities with respect to
information security.
What is information security?
• This is a general term which covers all aspects of computer security. It covers protection
against viruses and hackers, password and access control policies as well as
procedures for the regular backing up of your data (to guard against computer failure)
Advantages of proactive information security
• A proactive information security policy anticipates problems and attempts to guard
against future problems, as opposed to discovering a problem and then trying to deal
with the problem 'on the fly'.
Passwords
• If your computer has a password which prevents other users from accessing it then do
NOT give this password to anybody else. Do not write the password on a card and prop
this up next to the monitor and above all do not attempt to hide your access passwords
on the underside of your desk (this is the first place most criminals would look if trying to
break into your system). Make sure you do not forget your passwords; in many cases,
data cannot be recovered once the password is lost.
The Importance of shutting down your computer
• When you are using a Windows based system it is important to remember that just
switching off the computer or losing power due to a power cut (power outage) can cause
loss of data. To protect against this you should save your work regularly. Many programs
have a facility which automatically saves your work; say every 10 minutes (or any time
interval which you specify).
• Some operating systems, such as the later versions of Windows 95 and also Windows
NT have a facility which will automatically detect that the computer was not properly shut
down the last time it was used. If this situation is detected, then a special recovery
program will be run which will attempt to fix any damage caused by the power cut.
• When using Windows 95 or Windows NT, you MUST always use the shutdown
command (located on the Start menu) to close down the operating system, before
switching off the power.
What is a UPS?
• A UPS (Un-interruptible Power Supply) is a device which you can attach to your
computer which will guard against power cuts (or indeed someone tripping over your
power cable and pulling the plug out). It contains batteries which will keep your computer
alive long enough for you to use the shutdown command and turn off the computer in the
proper way. This is especially important for PCs on a network which might provide data
for many users on the network.
Electrical surge protection
• The voltage which is supplied to your computer via the power cable can vary from time to
time, and there are occasional power surges. Power surge protection devices are readily
available and offer low cost protection again these occasional power surges.
Things computers like
• Good ventilation
• Clean environment
• Stable, vibration free surface
Things to avoid
• Dust
• Drinking and eating over the keyboard
• Heat, Cold
• Moisture
• Do not move the system while it is switched on.
• Do not just switch the computer off at the mains. Follow the correct shutdown procedure
or data could be lost.
• Do not place objects on top of monitors. This could block the ventilation holes and cause
it to overheat.
• Do not place floppy disks near monitors. Monitors produce a strong electromagnetic
field, which can damage floppy disks.
What to do if the computer breaks down
• If you are working within a large organisation, you should be aware of the company’s
policy if the computer suddenly breaks down. Many large companies have a special
computer support department and you should make sure that you know how to contact
them in case of emergency.
In many smaller organisations, the situation is much less formalised. If you are not
qualified to make repairs on the computer, do NOT attempt to open the computer case
and investigate. This is especially true of the computer monitor, inside are many
components operating at VERY HIGH VOLTAGES, which can kill. If in doubt, get a
qualified technician to fix the problem.
• Prior to contacting your computer support staff you may (if authorised by your
organisation) check that the various external components, such as the mouse, keyboard,
monitor and network connections are in fact properly connected to the back of the
computer. A very common complaint to support groups is that the screen is not working.
You may wish to check that someone has not inadvertently switched off the screen, prior
to ringing the support group. One of the more common reasons for a network not
working is that someone (maybe an overnight cleaner) has accidentally pulled the
network cable out of the back of a computer.
Dealing with security problems
• In any organisation there should be clearly defined policies for the detection of security
problems, and what to do if a problem is noticed. Security problems may range from the
physical presence of unauthorised persons in an office, through to suspicion of
attempted unauthorised electronic entry to your computer networks.
In all cases you should know whom to contact, and how to contact the relevant person,
so that the matter can be investigated further.
Responsibilities for dealing with security problems
• If you are reporting a security problem, you should do so without delay, to the relevant
person within your organisation. If you are responsible for dealing with reports of security
incidents, you should always take action immediately, and follow the correct procedure
within your organisation for investigating any problems.
Security rights and obligations
• If you are working for a large organisation you have both rights and obligations to the
organisation. For instance does an employer have the right to video film and record
employees without their permission? Can an employer read all email sent and received
by employees? Can an employer monitor what Internet sites an employee is accessing?
The employer must make clear the security obligations of employees, such as keeping
network ID and logon passwords secure and how to report security incidents.
1.7.1.2 Know about privacy issues associated with computers, such as
adopting good password policies. Understand what is meant by user ID
and differentiate between user ID and password. Understand the term
access rights and know why access rights are important.
User IDs and passwords?
• A User ID is normally used to logon to a computer, or computer network. It uniquely
identifies you to the network. In addition you use a password which is only known to you.
The password guarantees that no one can access the network and impersonate you (in
theory). Once you have logged on (i.e. connected) to the rest of your computer network,
you will have been assigned access rights to the network. Your network administrator will
have defined these access rights. The idea of access rights is that you only have the
ability to connect to, or share, devices which you have authority to use. In other words,
the network administrators often have access rights to just about every computer, printer,
modem etc on the network. You on the other hand may have access rights to print to
only certain, specified printers and you may be able to access only certain data held on
the network.
Choosing a secure password
• Your password is the only thing which will prevent someone else logging into a computer
using your user ID and impersonating you. It is important to choose a password which
cannot be easily guessed by other people. Ideally a password should be at least 8
characters long & contain a mixture of words and numbers. It is also recommended that
you change your password regularly; some computer systems will require you to change
your password periodically.
How secure is your software?
• Microsoft Windows does seem notoriously easy for talented hackers to crack. It seems
that there are rather too many 'fixes' which companies such as Microsoft release and
then ask you to install to help plug some of the holes in their in-built security. As soon as
you connect a computer to a computer network or the Internet your risk of attack
increases. Applications are also vulnerable to attack. For instance there are some virus
programs which explore security weaknesses within Microsoft Word to spread
themselves and infect your computer.
How do your manage data securely?
• Make sure that there is a policy in place for the management of sensitive data, especially
if it involves the transmission of the information beyond your organisation. If you are
sending a fax or email, be sure that the message contains your contact information, and
a message describing the contents as confidential, with instructions for what to do if the
recipient has received the message in error. Logs should be kept of all faxes and emails
sent and received. Sensitive printed materials should be clearly marked, maybe with a
watermark saying CONFIDENTIAL or DRAFT ONLY.
How do you dispose of data securely?
• Floppy disks: If you perform a full re-format on a floppy disk, this will remove the data.
However be aware that there are programs available which will undo the effect of this
formatting. The only way to be sure that the data is removed is to physically destroy the
floppy disk.
Hard disks: If you delete a file, then it is actually only moved to the Recycle Bin. As a
first step, empty the Recycle Bin of deleted files. Even where a file appears complete
deleted, it can still often be recovered using specialist data recovery programs. Be
warned. If you are disposing of an old hard disk which used to contain sensitive data, the
safest way is to crush it.
Tape backups and removable drives (ZIP and JAZ drives): Apart from file deletion,
physical crushing of the media is the only totally safe way to guarantee that your data
remains secure.
Old Computers: When disposing of old computers, remove all data storage media and
crush them.
Paper output: Always put unwanted paper output through a paper shredder, prior to
disposal.
What is visitor control?
• When you let visitors into your building, they should always sign in. This is vital for fire
regulations, so that you know exactly who is in a building, in case of emergency.
• You can issue electronic badges to visitors. This often allows the movement of visitors to
be monitored electronically by your security staff. It can also be used to allow access to
certain areas of the building, but deny access to more sensitive areas.
• Electronic passes can also be used to control which members of staff have access to
which area of your building.
1.7.1.3 Know about the purposes and value of backing up data software
to a removable storage device
Why do you need to back up your computer?
• The most important thing which you store on your computer is information. Often the
contents of a hard disk can represent years of work. If the hard disk stops working one
day you could lose all those years of work. For this reason it is VITAL that you take
regular backups of the information which is stored on the computer. In large
organisations this backup procedure is normally performed automatically by your
computer support team, where the data is normally held on a centralised, networked
computer.
In smaller organisations, it is often up to the individual to organise some sort of data
backup. If nothing else is available, copy your files to a floppy disk and make sure that
these backup disks are stored away from the computer, ideally off-site. If there is a fire
and your office burns down, if your backup disks are stored next to the computer they too
will be incinerated.
Organising your computer for more efficient backups
• When you think about it, you have a computer containing many programs and also a
large amount of data which you have created, then it is only the data which really needs
to be backed up. If you create a folder structure which contains only data then only this
directory (plus any sub-directories of this directory) needs to be backed up.
Complete vs. incremental backups
• A complete backup means which you backup all the data on your computer. This has the
advantage that the entire hard disk can be backed up, but suffers from the disadvantage
that this process can take a long time if your computer contains a lot of data. An
incremental backup means that once a week you can perform a complete backup, but
every night for the rest of the week, you only backup files which have been newly
created or modified since the last backup, saving time. With the right backup software,
this process is automatic, and normally you only have to select full or incremental.
Why you should use 'off-site' storage?
• It is no good backing up your data only to leave the item which you backed up to next to
the computer; if someone steals your computer it is likely that they will also steal your
backups too. If you have a fire, then again you will lose your backups if the backups are
stored next to the computer. Ideally, backups should be stored off-site at a safe location.
At the very least, consider storing your backups in a fireproof safe, which will give some
protection against fire damage.
Beware of 'open files'
• You should perform backups at night. If you backup your computer during the day (when
you are using programs on the computer) then any program or data files which are in
use at the time of the backup will not be backed up. The backup program will skip these
'open' files.
1.7.1.4 Be aware of possible implications of theft of a laptop computer,
PDA, mobile phone such as: possible misuse of confidential files, loss
of files, loss of important contact details if not available on a separate
source, possible misuse of telephone numbers.
What if your laptop is stolen?
• If there was no start-up password then all the data on the computer could be at risk. The
same goes for important/sensitive documents; if these were not individually password
protected they could also be vulnerable. If you work within a large organisation, always
report an incident of this type immediately to your technical support department.
What if your mobile phone is stolen?
• Call your technical support department if working for a large organisation. If you work
alone, then call the phone network operator and report the phone as stolen.
1.7.2 Computer Viruses
1.7.2.1 Understand the term virus when used in computing and
understand that there are different types of virus. Be aware when and
how viruses can enter a computer system.
What are computer viruses?
• Viruses are small programs which hide themselves on your disks (both diskettes and
your hard disk). Unless you use virus detection software, the first time that you know that
you have a virus is when it activates. Different viruses are activated in different ways. For
instance, the famous Friday the 13th virus will activate only when it is both a Friday and
the 13th of the month.
BEWARE: Viruses can destroy all your data.
How do viruses infect PCs?
• Viruses hide on a disk and when you access the disk (either a diskette or another hard
disk over a network) the virus program will start and infect your computer. The worst
thing about a computer virus is that it can spread from one computer to another, either
via use of infected floppy disk, or over a computer network. The Internet allows you to
access files from all over the world and you should never connect to the Internet unless
you have a virus-checking program installed on your computer. It is vital to keep your
virus monitoring software up to date. Many anti-virus programs, such as Norton Anti
Virus allow you to update the program so that the program can check for recently
discovered viruses.
More Information:
McAfee Anti-virus software http://www.mcafee.com
Norton Anti-virus software http://www.symantec.com/avcenter
Dr Solomon anti-virus software http://www.drsolomon.com
How to prevent virus damage
• There are a number of third party anti-virus products available. The main thing about
your virus checker is that it should be kept up to date. Many companies supply updated
disks on a regular basis or allow you to receive updates automatically via the Internet.
To make a diskette read-only
• If you are using 3 1/2” diskette (floppy disk), there is a notch which can be opened or
closed which may be used to protect the disk. To protect the contents of the disk move
the notch to the open position (you should be able to see through the hole).
To password protect your computer
• You can set a power-on password on your computer. The mechanism for setting this will
vary from one computer to another, and is determined by the makers of the computer,
rather than by Windows. The advantage of a power-on password is that the computer
will not boot to Windows until you supply the correct password. This means that no one
else can play around with your computer and in the process accidentally infect it with a
virus.
1.7.2.2 Know about anti-virus measures and what to do when a virus
infects a computer. Be aware of the limitations of anti-virus software.
Understand what ‘disinfecting’ files means.
How do your protect computers from attack?
• The safest way to use a computer is to not connect it to a Local Area network or the
Internet. This is called a 'stand-alone' computer, providing that you do not use floppy
disks on that PC which have been used in other computers, this type of computer is
virtually immune from any form of intrusion.
• Unfortunately it is the ability to connect to other computers or indeed the Internet, which
makes the modern computer so versatile and so useful.
• Always make sure that all computers require an ID and password to access them. Make
sure that all relevant 'security patches' from Microsoft have been applied.
• Make sure that the password is long enough, contains a random mixture of numbers and
letters, and that the passwords are changed on a regular basis.
• There are many examples, where people have used passwords which relate to
something personal, such as a partner’s first name, the dog’s or cat’s name, etc. For a
determined, serious computer hacker, these are easy to guess. If you have a system,
where lots of different passwords are required to access the system, then security often
breaks down and computer users will sometimes keep a list of these passwords in their
disk. This defeats the whole object. If you forget your network access password, the
network administrator should be able to assign you with a new one.
What to do if you discover a virus on your computer
• If you discover a virus on your computer don’t panic. If your virus checker alerts you to a
virus, then the chances are that it has caught the virus before the virus could infect your
computer and cause damage. For instance you may insert a diskette into your computer
and the virus checker should automatically scan the diskette. If the diskette contains a
virus, a message will be displayed telling you that the diskette is infected, and it should
automatically remove the virus. The other common method of infection is via emails.
• If you work within a larger company, you should have a company IT support group which
will come and rid your computer of viruses. Be sure that you are familiar with your
company’s policy regarding viruses.
The limitations of anti virus software
• Anti virus software can only detect viruses (or types of viruses) which the software knows
about. As such it is vital that you keep your anti virus software up to date so that it can
detect new viruses which are constantly appearing.
What is virus disinfecting?
• Running a virus checker on a machine which contains a virus is known as disinfecting
the PC, as the virus program will detect, and then eliminate the virus.
1.7.2.3 Understand good practice when downloading files, accessing file
attachments, such as: use of virus scanning software, not opening
unrecognised e-mail messages, not opening attachments contained
within unrecognised e-mail messages.
Anti-virus Precautions
• You should have an anti-virus program installed on your computer. This should be
updated on a regular basis, so that the anti-virus program is aware of new viruses which
are in circulation. Even the best anti-virus program will only offer protection against
known viruses or viruses which work in a particular way. New types of viruses are
constantly being developed which may attack your computer in new and novel ways.
Your anti-virus program may not be able to defend you against every possibility. Be
warned, if you are connected to a Local Area Network (LAN), or to the Internet you are
vulnerable.
Make sure that your virus checker is configured so that as well as scanning your
computer for viruses when you first switch on your PC, it remains active in the
computer’s background memory, constantly looking for signs of virus attack. This is very
important when connecting to the Internet.
Take care when opening emails:
Be very cautious about opening unsolicited emails, especially if they contain file
attachments. A good anti-virus program should detect most threats from virus-infected
emails.
Beware of Internet Downloads:
Any file which you download from the Internet may in theory contain a virus. Be
especially careful about downloading program files (files with a file name extension of
.COM or .EXE). Microsoft Word or Excel files can contain macro viruses. Basically trust
no one when it comes to downloading files. Do not connect to the Internet unless you
have a good anti-virus program installed on your computer.

ICDL Module 1 (IT) lec (3)

 Health and Safety, Environment
1.6.1 Ergonomics
1.6.1.1 Understand what elements and practices can help create a good,
working environment such as: appropriate positioning of monitors,
keyboards and adjustable chairs, use of a mouse mat, use of a monitor
filter, provision of adequate lighting and ventilation, frequent breaks
away from the computer.
Good working practices
• Includes the following:
Your chair:
Your chair should be fully adjustable, and be able to be moved up or down. It should
have an adjustable back.
Your screen:
Your screen should be fully adjustable so that your eyes are at the same height as the
top of the screen. You may wish to use a filter attached to the screen to reduce glare. If
the screen is badly focused, too bright or appears to flicker, then get a qualified
technician to take a look at it. You should periodically refocus into the distance, as
opposed to always gazing at a screen a few inches from your eyes.
Your keyboard:
Use a good keyboard and you may also wish to use a wrist pad to relieve pressure on
your wrists.
Your feet:
You may wish to use a footpad to rest your feet while using the computer.
Your mouse:
Use a mouse mat to make the mouse easier to use. Ensure that you have enough space
to comfortably use the mouse. If your arms or fingers become tired or painful when using
the mouse, take a break and do something else.
Breaks:
Take frequent breaks when using a computer.
Other factors:
Make sure that the area where you are using the computer is adequately lit and well
ventilated. Ventilation is especially important if you are using a laser printer, which may
produce ozone when printing.
1.6.2 Health Issues
1.6.2.1 List some common health problems which can be associated
with using a computer such as: injuries to wrists caused by prolonged
typing, eye strain caused by screen glare, back problems associated
with poor seating or bad posture.
Using a computer incorrectly can damage your health
• Take regular breaks, have regular eye tests and get a good desk and chair to maintain
good posture.
Repetitive Strain Injury (RSI)
• Often referred to as RSI. This is a condition caused by constant use of the keyboard or
mouse. You should take regular breaks to help avoid this type of injury. You may want to
consider the use of a pad on which you can rest your arms, which will help to some
extent.
More information: http://www.rsi-center.com
Glare from screens
• You should take regular breaks to avoid staring constantly at the screen and straining
your eyes. You should consider using the best (i.e. most expensive) monitor which you
or your company can afford. The better the monitor the better the screen resolution and
the higher the refresh rate. For detailed work, you should also consider using a large
screen rather than the 'standard' 14" or 15" screens which are in common use. In many
countries, your employer has a legal duty to pay for eye tests for employees as and
when they request it. You can get filters which fit in front of the screen and reduce glare.
Bad posture
• When sitting at your computer you should have a monitor at eye level which can be
adjusted to suit you. In addition, you may want to consider a footrest. Neck ache and
backache can result from prolonged bad posture.
1.6.3 Precautions
1.6.3.1 List some safety precautions when using a computer such as:
ensuring power cables are safely secured, power points are not
overloaded.
Make sure that cables are safely secured
• You should always use the power cables which were supplied with your computer or
cables of a similar quality. Make sure that the cables are safely secured at the back of
the desk and that you have power points located near the desk. If your desk has a cable
ducting system make sure that you use it. Avoid long trailing cables as you or other
people can easily trip over them and cause injury to yourself or others. Apart from
personal injury, accidentally pulling out a power cable could cause your computer to lose
power and you will lose data as a result. Network cables tend to be delicate and easily
damaged and the most common cause of failure to log onto a network server is that
someone has accidentally dislodged or damaged the network cables.
Make sure that power points are not overloaded
• Overloading of a power point is dangerous and a potential fire hazard. If you need more
power sockets, have them properly installed by a qualified electrician.
1.6.4 The Environment
1.6.4.1 Be aware that recycling printed outputs, recycling printer toner
cartridges, using a monitor which consumes less power while the
computer is inactive can help the environment.
Computers and the environment
• You should have a separate bin for paper which can be sent for recycling (be sure that
sensitive material is first shredded).
Printer toner cartridges can be sent for recycling; in fact some charities now collect spent
toner cartridges, and send them for recycling. You may also wish to consider the use of
recycled toners in your printers (but be aware that in some cases this may invalidate the
printer’s guarantee).
Many monitors and other peripherals will automatically switch into 'sleep' mode after a
period of inactivity. This means that even though the computer is still switched on, it will
consume less power.
1.6.4.2 Understand that using electronic documents can help reduce the
need for printed materials.
Don’t Waste Paper
• Where possible the use of on-screen manuals and help systems, rather than printed
manuals, will save on the amount of paper consumed. This equates to less trees being
cut down.

ICDL Module 1 (IT) lec (2)

1.4 Information Networks
1.4.1 LAN and WAN
1.4.1.1 Understand the terms, local area network (LAN), wide area
network (WAN). Understand the term client/server.
What is a LAN (local Area Network)?
• A LAN (Local Area Network) is a system whereby individual PCs are connected together
within a company or organisation. For instance if ten people are working together within
an office it makes sense for them all to be connected. In this way, the office can have a
single printer and all ten people can print to it. In a similar way, other devices such as
modems or scanners can be shared. Even more useful is the ability to share information
when connected to a network.
What is a WAN?
• A WAN (Wide Area Network) as the name implies allows you to connect to other
computers over a wider area (i.e. the whole world).
What does client/server mean?
• This term relates to the type of network where resources are kept centrally on the server
and used locally by the client. The server tends to be a very powerful PC (or group of
PCs), while each client workstation, which the users have, is less powerful.
1.4.1.2 List some of the advantages associated with group working such
as: sharing printers, applications, and files across a network.
What is workgroup computing?
• The idea of a workgroup is that groups of people working together can share their
resources with each other. People within the workgroup can share information on their
hard disks as well as sharing printers, modems and scanners. The workgroup is
connected via a computer network. This network can simply consist of a few computers
at a single location physically connected to each other via a network cable, or it may be a
workgroup of computers connected globally via the Internet. The networked nature of
computers means that the physical distance between workgroups members is fast
becoming irrelevant.
• Many programs are designed to be used within a workgroup. For instance when using a
word-processor you may use what are called templates. Your organisation might want to
use a standard Fax header sheet. If a template for this header sheet is held on a single
computer but available to all the other computers then this has the advantage that when
you need to make a change to the Fax header you only have to change one file, rather
than change the files on each computer.
Advantages of workgroup computing
• As there is no reliance on a central computer, there is less chance of major disruption if
one computer goes down for a while.
• Provided members of the workgroup have the authority and access rights, they can
share data on a temporary basis with colleagues, as required, without the need for a
network administrator to get involved.
• In small offices there may be no need for a dedicated network administrator, and this can
result in considerable cost savings.
Disadvantages of workgroup computing
• If you share files on your PC with many other people, this can slow down the running of
your PC.
• The security of the computer network may not be as good as the traditional client/server
network arrangement.
• You may give total access to the files on your PC, which may then be damaged or even
deleted, by other members of the workgroup.
1.4.2 Intranet, Extranet
1.4.2.1 Understand what an Intranet is and understand the distinction
between the Internet and an Intranet.
What is the difference between the Internet and an Intranet?
• An Intranet is a smaller, closed version of the Internet, which can only be accessed by
authorised members of an organisation. Intranets are becoming an increasingly popular
way to share information within a company or other organisation. An Intranet uses
Internet technologies to allow users to access company documents, search databases,
schedule meetings and of course send emails. Once a company has installed a
comprehensive Intranet many users need only one piece of software on their PC, a web
browser.
1.4.2.2 Understand what an Extranet is and understand the distinction
between an Intranet and an Extranet.
What is the difference between an Intranet and an Extranet?
• An Extranet is an Intranet which is partially accessible to authorised outsiders. An
Intranet is normally only accessible by members of the same company or organisation;
an extranet also allows outsiders who have been issued with a password to gain limited
access to information held on a company network. Extranets are being used as a way for
business partners to share information.
1.4.3 The Internet
What is the Internet?
• A collection of networks started by and for the US military to enable them to 'survive' a
nuclear war. Later adopted by the educational system, and now exploited by the
commercial world.
1.4.3.1 Understand what the Internet is and know some of its main uses.
What is the Internet and how is it useful?
• The Internet is a global network of interconnected networks. The unique thing about the
Internet is the sheer amount of information which you can access from it. Whatever your
interest, you can search for and find information on the most obscure topics. For
research the Internet is an incredibly valuable tool. Whether you are gathering
information about a rival company on the other side of the world, or are looking for
information about your family tree, you will find there is plenty of information available. If
you publish material on the Web, it can be accessed by everyone on the Web (providing
they can find it.). As a marketing tool, this has interesting possibilities. It is possible for a
small company to sell products and services worldwide, without the need for a single
sales-person. These days the problem is often not finding information but rather dealing
with the sheer amount of information which is available. Also, you have no idea how
accurate or up to date a lot of the information you access really is.
More information about search engines: http://www.searchenginewatch.com
1.4.3.2 Understand what the World Wide Web (WWW) is and distinguish
it from the Internet.
What is the difference between the World Wide Web (WWW) and the Internet?
• The World Wide Web (WWW) is just a small part of the Internet as a whole. The Internet
relates to all the hardware and software involved, as well as the WWW, it also includes
FTP (File Transfer Protocol), email and newsgroups. The WWW is basically the text and
pictures which you can view using your web browser, such as Microsoft Internet
Explorer, or Netscape Navigator.
1.4.4 The Telephone Network in Computing
1.4.4.1 Understand the use of the telephone network in computing.
Understand the terms Public Switched Telephone Network (PSTN),
Integrated Services Digital Network (ISDN), Asymmetric Digital
Subscriber Line (ADSL).
How is the telephone line used in computing?
• If you use a modem to connect to the Internet, then this connection is made via the
telephone network.
Where to get help about technical terms
• Check out an excellent site, which you can find at:
http://www.webopedia.com
What is PSTN?
• PSTN (or Public Switched Telephone Network) is the technical name for the public
telephone system. It is based on traditional 'copper wire' technology and can transmit
analogue voice data.
What is PSDN?
• PSDN (or Public Switched Data Network) is simply the technical name for the telephone
system in use today.
What is ISDN?
• Stands for "Integrated Services Digital Network." ISDN dates back to 1984, and allows
much faster transfer rates than when using modems. Using ISDN, you can transfer 64
Kbit or 128 Kbit of data per second.
What is ADSL?
• Short for 'Asymmetric Digital Subscriber Line'. A more recent technology which allows
more data to be sent over existing copper telephone lines, but requires a special ADSL
modem.
• ADSL allows data transfer rates of ranging from 0.5 to 8 Mbps when receiving data
(called the downstream rate) and from 16 to 640 Kbps when sending data (called the
upstream rate).
What is DSL?
• Refers collectively to all types of 'Digital Subscriber Lines', the two main categories
being ADSL and SDSL. DSL technology allows faster data transfer while still using
copper wires (as opposed to optic fibre cables).
1.4.4.2 Understand the terms analogue, digital, modem, transfer rate,
(measured in bps – bits per second).
Digital vs. analogue
• A digital system uses 1 or 0 to transmit data or to represent data. Thus, a digital clock
will display whole seconds, whole minutes and whole hours. An analogue system, such
as a traditional clock, does not use multiples of 1 or 0, but rather uses the full range of
numbers, including fractions. In this way, an analogue clock can display fractions of a
second.
Modem
• Modem stands for “MODulate/DEModulate”. The modem sends information from your
computer across the telephone system. The modem at the other end of the phone line,
converts the signal back into a format which can be used by the receiving computer.
Baud rate
• The baud rate tells you how fast a modem can send/receive data. Most modern modems
have a maximum baud rate of 56 Kilobits per second (Kb/sec).
1.5 The Use of IT in Everyday Life
1.5.1 Computers at Work
1.5.1.1 Identify some situations where a computer might be more
appropriate than a person for carrying out a task and where not.
Where computers might be more appropriate than people
• Repetitive tasks: In the past, many repetitive jobs were performed by low skilled, poorly
paid workers. Now is it more common to use computers instead.
• Easily automated tasks: The phone system is now largely automatic, while in former
times all calls were made through an operator. Many other examples exist. How many
can you think of?
• Mathematical calculations: A computer is ideally suited to performing mathematical
calculations. Before computers were widely available accountants used to work on
manual, paper-based spreadsheets. Within a spreadsheet, a common task would be
adding up a column of figures, and then taking the total, which is added to other columns
of figures. If you change one number within a column which is being summed, there can
be a knock-on effect on many other calculations within the spreadsheet. Re-calculating a
spreadsheet could take hours (or days). On a computer, this re-calculation can take
seconds.
• Dangerous situations: Monitoring of polluted or radioactive environments is suited to
computer-based robots, where the use of a human would expose that person to
unacceptable risks. Unmanned, computer-controlled machines almost exclusively carry
out serious space exploration. A recent exploration of Mars involved a computerised
‘car’, which had to make decisions on its own. It could not be remotely controlled from
earth, as the time taken for the signal to reach Mars is just too long.
Where people might be more appropriate than computers
• Computers have their limits (how do Daleks from the TV series “Dr Who” cope with
stairs?)
• When you are unwell and visit your doctor, it is often a person to whom you want to talk,
as there might well be other factors affecting your health (maybe personal problems)
which you would not feel happy typing into a computer, but would feel comfortable
describing to your local doctor, whom you may well have known for years. In most of the
caring professions, the same is true, whether it be doctors, nurses or social workers. The
human touch is important.
• Despite the uptake of e-commerce, (selling on the Net, banking on the Net and so on),
there are many people (myself included) who still like to have the option of a real person
to whom you can talk, be it the local bank manager or a real person on the end of a
telephone sales line. Does anyone like ringing a large organisation and being greeted
with a range of buttons to press, in order to communicate with a computerised telephone
system? Even ordering cinema tickets can now involve a lengthy phone call, listening to
a synthetic voice describing many films you do not want to see, and pressing many
buttons.
• For many years, science fiction has portrayed images of a thinking, sentient android
(Lieutenant Data from Star Trek for instance). In reality this is a long way from present
capabilities and when it comes to anything requiring creative thought, a human wins
every time. Computers in their present form would gain little from studying philosophy for
instance. They can memorise the facts, but cannot make the creative leaps which
humans can. On a more mundane level, when it comes to even a simple task such as
cleaning your home, a human can deal with mess, clutter and items (such as chairs)
which have changed their position recently. Even this simple task is beyond a small
computer.
• Computers are very bad at recognising and interpreting shapes. They can take
photographs and record images on video, but they have no understanding of the
meaning of shapes, and will be easily confused when presented with two overlapping
shapes. The human process of pattern recognition, as recent research had
demonstrated, is vastly more complicated than we used to think. For these reasons it is
humans, not computers who will examine tissue smears for signs of abnormality within
hospitals.
• In time things may change, it was not very long ago that a computer was incapable of
beating a chess grand master.
1.5.1.2 Know some of the uses of large-scale computer applications in
business such as: business administration systems, airline booking
systems, insurance claims processing, online banking.
Examples of large scale computer applications in business
• Business administration systems: The classic use of a computer is to run business
administration systems, and all aspects of this have now been computerised.
• Airline booking systems: Airline booking systems have long been computerised. This
maximises profit for the airline companies and is often more convenience for the
customer. Many of these airline-booking systems have now also been integrated with
online airline ticket sales.
• Insurance claims processing: All insurance companies use very large mainframe
computers, combined with specialist software to manage their business. The software
involved can handle all aspects of claims procedures. As with many large-scale systems,
some insurance companies have invested in over ambitious computerisation and there
are numerous examples where many millions have been wasted over the years.
• Online banking: Most banks now offer some form of online banking. This has the
advantage to the bank that costs can be reduced. Some banks are completely online,
with no physical branches at all. The customers benefit from 24-hour access to banking
services. The downside is that this leads too many job losses in the banking industry and
when things go wrong there is no physical person you can go and see and make your
complaints to. Some leading banks have demonstrated a degree of incompetence when
it comes to the security of their online systems and many people are very reluctant to
trust online banking systems yet.

1.5.1.3 Know some of the uses of large-scale computer applications in
government such as: public records systems (census, vehicle
registration), revenue collection, electronic voting.
Uses of large scale computers applications within government
• Census: Every few years census details are taken and entered into large computer
databases. This data can then be used to extract useful information and predict trends.
In some cases this data is also being made available online, so that it becomes even
more accessible and useful.
• Vehicle registration: All car and lorry details are kept centrally; this makes it easy to find
the owners of cars, which can be useful for police, customs and security services.
• Revenue collection: Increasingly aspects of government revenue collection are being
computerised, which in many cases involves online systems as well.
• Electronic voting: Governments are experimenting with online voting systems, often in
response to appallingly low voter turnout. Security remains the main obstacle to the
extension of this idea.
www.ukonline.gov.uk
1.5.1.4 Know some of the uses of large-scale computer applications in
hospitals/healthcare such as: patient records systems, ambulance
control systems, diagnostic tools and instruments, specialist surgical
equipment.
Uses of computer applications within hospitals and the health care system
• Patient record systems: Appointment and record systems are computerised and
centralised. This means that doctors at one location can access medical records from
another location. The results of tests can be emailed rather than being posted, which
speeds up treatment.
• Ambulance control systems: Ambulances are often centrally controlled and the
computer systems can now integrate satellite positioning to pinpoint the location of each
ambulance. In times of large scale disasters, ambulances from different regions can be
coordinated.
• Diagnostic tools and specialist surgical equipment: The modern intensive care
facility is filled with computerised diagnostic equipment. Even the doctor’s surgery is
increasing being taken over by computers, which will monitor heart rate, blood pressure
etc.
1.5.1.5 Know some of the uses of computer applications in education
such as: student registration and timetabling systems, computer-based
training (CBT), distance learning, homework using the Internet.
Uses of computer applications in education
• Student registration and timetabling: There are many specialist programs designed to
computerise these otherwise time consuming tasks.
• Computer Based Training (CBT): Computer Based Training (CBT) offers a low cost
solution to training needs where you need to train a large amount of people on a single
subject. These programs are normally supplied on CD-ROM / DVD and combine text,
graphics and sound. Packages range from general encyclopaedias right through to
learning a foreign language. As an alternative to training via CD-ROM / DVD, CBT can
also be delivered via the Internet.
• Using the Internet as a homework resource: The Internet is the ultimate resource for
getting the information necessary to complete a student’s homework. The Internet can
also be used to set and collect homework (via email).
• Distance learning systems: E-learning is a term used to describe studying via the
Internet. It can take many forms ranging from a simple web version of printed books,
through to advanced use of video images with sound. In many cases there can be realtime
two-way communication between the teacher and the student.
Advantages include:
- One trainer can train many people at many different locations.
- If the training is solely computer based, then the students can work at their own pace,
and repeat parts of a course which they do not understand. Also the teaching can be at
any time, 24 hours a day, 7 days a week.
- Often e-learning solutions are cheaper to provide than other more traditional teaching
methods.
Disadvantages include:
- There may be no opportunity to ask a question of a real person.
- The Internet connection may temporarily fail for some reason.
- You may have to pay for the connection time, by the minute.
- The download speed may be too slow for some forms of e-learning
- Because of the increased time required to produce some types of e-learning packages,
the e-learning tutorials may not be available for some time following the release of a new
version of software, or a new certification syllabus.
1.5.1.6 Understand the term tele-working. List some of the advantages of
tele-working such as: reduced or no commuting time, greater ability to
focus on one task, flexible schedules, reduced company space
requirements. List some disadvantages of tele-working such as: lack of
human contact, less emphasis on teamwork.
What is tele-working?
• Tele-working is a broad term which refers to people working at home connected to the
rest of the organisation via a computer network. Communication is via email or the
telephone. This arrangement has advantages and disadvantages to both the employer
and the employee.
Some of the advantages of tele-working
• Advantages include:
Reduced or zero commuting time.
This saves time (and money) for the employee and reduces environmental overheads,
as less commuting means less car pollution. It means that the employee does not arrive
at work already stressed from car jams or late train connections.
Greater ability to focus on one task:
As there are fewer interruptions from low priority phone calls, there is a greater ability to
concentrate and focus.
Flexible schedules:
In many cases, as long as the job gets done, it does not matter when the job gets done.
This means there is time for other activities, such as picking up the kids from school. It
also means that work can be finished in the evening if required. If it is a beautiful day,
why not take advantage of the weather, and finish your work later.
Reduced office desk space requirements:
The cost of Office space can be very high and tele-working can help to reduce these
costs if a proportion of the staff work at home. "Hot Desking" is a term used to indicate
that people do not have a desk dedicated to their exclusive use. People simply sit at any
desk and log on to the networked computers using their own ID, which will allow them to
uniquely access their own work stored within the computer system. Hot Desking is
popular where staff spend a proportion of their time working at home, or at sites outside
the main office complex.
Some of the disadvantages of tele-working
• As well as advantages, there are many disadvantages for tele-workers, which include:
Lack of human contact:
Many people cite this as the single biggest factor when switching from a regular office
job, to tele-working. In fact many companies now arrange company gossip networks, just
so that people can keep in touch.
Negative impact on teamwork:
If you never see the rest of the team it is hard to feel part of the team. To some extent
this is offset by video links and by occasional get-together meetings.
Self-discipline:
It can take a lot to work from home and remain focused on work. It is all very well saying
'I will take the afternoon off and work this evening', but come the evening you may not
feel like working.
Possible Employee Exploitation:
If workers are isolated from each other there is the possibility for companies to take
1.5.2 Electronic World
1.5.2.1 Understand the term electronic mail (e-mail) and know its main
uses.
What is email?
• Email allows you to send a message to another person almost instantly, anywhere in the
world. It requires both computers to be connected to the Internet. As well as sending a
text message, files can be sent as email attachments.
1.5.2.2 Understand the term e-Commerce. Understand the concept of
purchasing goods and services online, including giving personal details
before a transaction can be carried out, payment methods, consumer’s
basic right to return unsatisfactory goods.
What is E-commerce?
• The phrase e-commerce is a buzzword which relates to buying or selling via the Internet.
Increasingly you can purchase directly via a Web site by selecting the goods or services
which you require and entering your credit card details. When you send your credit card
details these SHOULD be encrypted by the site operators so that no one can intercept
your details. Most sites which accept credit card payment are on secure services and
your Internet browser program (i.e. Microsoft Internet Explorer or Netscape
Communicator) will normally inform you (via a popup) when you are entering or leaving a
secure server.
What is E-banking?
• The phrase e-banking relates to managing your money online. Instead of having to go to
the local branch, or telephoning them, you can pay your bills online and move money
from one place to another. Some online banks have no physical branches at all, making
it a very profitable operation for the bank. There are security considerations relating to
online banking, with numerous examples of poor security coupled with sloppy
operations.
The process of shopping online
• There are numerous web sites from where you can purchase online, the most famous of
all being amazon.com as illustrated. Most Internet based shopping sites use a virtual
“shopping cart” system. As you browse the site you can add any products you want to
purchase to your cart. Once you have placed items in the cart you can then move to the
checkout stage. At the checkout you enter your name & address, select the type of
delivery you want and enter your payment details.
1.5.2.3 List some of the advantages of purchasing goods and services
online, such as: services available 24 hours a day, opportunity to view a
wide range of products. List some of the disadvantages of purchasing
goods and services online such as: choosing from a virtual store, no
human contact, risk of insecure payment methods.
The advantages of e-commerce
• There are many advantages using e-commerce:
Services available 24 / 7:
Unlike a normal shop which closes in the evening, you can shop via the Internet 24
hours a day, 7 days a week, and 365 days a year.
Large stock range:
A larger range of stock can be carried than a conventional store. The stock does not
have to be distributed and duplicated over many physical stores, but rather it can be held
in one central distribution warehouse.
Detailed product information:
A detailed product description for each product, along with a picture can be given. There
can even be links to the product manufactures own web site.
Ability to compare prices:
Many sites claim to offer you the very best prices. You can use the information on these
sites to compare prices.
Equal delivery to town and country:
The fact that you may live in the countryside, far from the nearest town makes no
difference at all when shopping via the Net.
Right to return defective goods:
Most e-commerce web sites will have a 'Returns Policy' and it is advisable to read this
prior to purchase. In many cases you will find that the law gives you a right to return
defective goods or even goods which are not quite as you expected.
The disadvantages of e-commerce
• Includes the following:
Possible Credit card Fraud:
Some web sites have been set up solely to trick you into providing your credit card
details, which can later be sold to criminals so that they can make purchases with your
money. When it comes to credit card fraud there is basically one rule 'wherever humanly
possible the bank never pays: - someone else does', make sure that someone is not you.
Check the small print on your credit card agreement.
Is the web site genuine?:
When you purchase from a company such as amazon.com, you know that the company
is well respected, is unlikely to go bust tomorrow, and above all will not attempt to 'run off
with your money'. But what about when you purchase online from a company you have
never heard of? Look for clues. Is there a client list on the site? How long has the
company been trading. Are full contact details provided? If in doubt ring the phone
numbers provided on the site and try to decide whether the company sounds genuine.
Ask for references from other customers. Just because you see trade association logos
on a site, do not assume that the use of these logos is genuine. There are organisations
now whose sole purpose is to verify that other web sites belong to honest companies.
What about returning faulty goods?:
If the goods arrive and are substandard, who pays to return them. Where do you return
them to? Be sure you know about a company’s returns policy, BEFORE you make an
online purchase.
How are you covered when you purchase goods from another country?
This is a minefield. Each country may have its own laws relating to consumer protection.
Be warned!
Can you talk to a real person?
I recently heard a radio presenter who purchased a computer online, through a very well
known PC manufacturer. He purchased the computer for his daughter, in good time for
Christmas. As Christmas due near he tried to find out what was happening, but was
unable to talk to a real person and was forced to rely solely on email contact with the
company. The computer eventually turned up in February. Never buy from a company
which does not provide you with full contact details including a telephone number.
.