Cambridge IGCSE0417

Physical safety

Information Communication Technology 0417 Chapter Notes

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Physical safetyeSafetySecurity of data

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Physical safety notes

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1. Electrocution

A safety issue is a danger that can physically hurt the person. It is not damage to the device, and it is not a health issue such as eye strain or back pain.

Electrocution happens when a person touches live cables, or when a drink is spilled near electrical equipment.

To prevent it, do not place liquid near the computer equipment, and do not touch live cables. Say what the electrocution comes from: the live cable or the spilt drink.

Examiner insight

“Many of the answers given by candidates lacked detail and therefore could not achieve credit. For example, electrocution without stating from what or how.” “Some candidates wrote that drink should not be taken into a computer room but in order to gain credit they must go onto write that liquid should not be placed near the computer equipment.”

Worked example 13 marks

A school computer room has a drinks machine in the corner. Pupils sometimes carry drinks to their computers. Describe one safety issue and how it can be prevented.

1
Safety issue: electrocution. [1]
2
caused by a drink being spilled onto the electrical equipment. [1]
3
Prevention: do not place liquid near the computer equipment. [1]

2. Fire

Fire can start when a socket is overloaded: too many devices are plugged into it.

Fire can also start when equipment overheats.

To prevent it, do not plug too many devices into one socket. Name the issue as fire. The danger is to the person, so do not write about the equipment being damaged.

Examiner insight

“Some candidates were able to give the correct answer which was fire although some gave explode.” “In some cases candidates thought that the safety referred to damaging the equipment rather than the user.”

Worked example 13 marks

An office manager plugs six computers and two printers into one socket. Explain the safety issue this causes and how it can be prevented.

1
Safety issue: fire. [1]
2
because the socket is overloaded. [1]
3
Prevention: plug fewer devices into the socket. [1]

3. Tripping over trailing cables

Tripping is caused by trailing cables. A person trips over the cable and is hurt.

To prevent it, place the cables in ducts. Another way is to use wireless technology.

‘Trailing wires’ on its own lacks precision. Say that a person trips over them. A trailing lead is a safety issue: it has nothing to do with security or fake websites.

Examiner insight

“Those candidates that gained good marks wrote about the cables being placed in ducts or that wireless technology should be used.” “Some candidates misread the question and thought trailing leads meant some kind of security issue – leading people to fake websites.”

Worked example 13 marks

In a café, the cables that join four computers to a printer run across the floor. Describe one safety issue and two ways it can be prevented.

1
Safety issue: people may trip over the trailing cables and be injured. [1]
2
Prevention: place the cables in ducts. [1]
3
Prevention: use wireless technology to connect the printer. [1]

4. Heavy equipment falling

Heavy equipment can fall and injure people. An example is a projector falling and hurting someone.

To prevent it, place heavy equipment on a surface that is strong enough to hold it.

‘Heavy objects falling’ on its own lacks precision. Say what falls, and that it injures a person. This is a separate issue from trailing cables, so do not mix the two up.

Examiner insight

“The Examiners allowed answers like ‘the projector falling and hurting someone’ or ‘tripping over lose cables’.” “The candidates who did give safety concerns answered the question quite well, a few candidates lacked of precision in their answers, e.g. ‘trailing wires’, ‘heavy objects falling’, ‘fire extinguisher’.”

Worked example 13 marks

A school keeps a large projector on a narrow shelf above the classroom door. Describe one safety issue and how it can be prevented.

1
Safety issue: the projector is heavy equipment and may fall. [1]
2
injuring a person below it. [1]
3
Prevention: place the projector on a surface that is strong enough to hold it. [1]

5. Safety, not health or security

The topic asks for safety issues. Each has a cause and a way to prevent it.

A health issue, such as eye strain, headaches or back pain, is a different topic. Computer security is a different topic too. Neither earns marks on a safety question.

Keep the issue apart from the prevention, which is what is done to minimise the risk.

Examiner insight

“A large number of candidates gave answers for health or computer security and therefore obtained no marks.” “Some candidates mixed up the ‘safety issue’ with the ‘minimise the risk’.”

Worked example 14 marks

A question asks for two safety issues in a computer room. A student writes: ‘Sitting badly gives me back pain, and I may also be hacked.’ Explain why neither point earns a mark, and give one answer that would.

1
Back pain is a health issue, not a safety issue. [1]
2
Being hacked is a security issue, not a safety issue. [1]
3
A correct answer: electrocution. [1]
4
from touching a live cable. [1]

Recap

A safety issue is a danger of physical injury to a person, not damage to the device.
Electrocution: touching live cables, or spilling a drink near electrical equipment.
Fire: an overloaded socket, or equipment that overheats.
Tripping: trailing cables. Use ducts or wireless technology.
Heavy equipment can fall and injure people. Say what falls and who is hurt.

6. Data protection

A data protection act is legislation that protects personal data. It is required because personal data must be kept confidential and protected to avoid inappropriate disclosure.

Keeping data confidential and secure is part of a typical act. A question can ask for principles apart from these two.

Learn each principle as a whole statement. Give the principle, not just an item that relates to it.

Examiner insight

“In order for candidates to improve the answering of this type of question the principles need to be learnt in full, many candidates knew the principles, but some tended to split them into parts, therefore not achieving the mark.” “Many candidates gave examples of the elements within an act but did not expand their answers to state the principle of a data protection act that this related to.”

Worked example 12 marks

A school holds the names, addresses and medical history of its students. Explain why data protection legislation is required.

1
Personal data must be kept confidential and protected [1]
2
to avoid inappropriate disclosure of the students' data [1]

7. Personal data and sensitive data

Personal data is data that could be used to identify an individual. Examples are a personal name, an address, a date of birth, a photograph in school uniform and medical history.

Examiners treat sensitive data as a category of personal data. Examples they give are ethnicity and political views.

Personal data must be kept confidential and protected to avoid inappropriate disclosure.

Examiner insight

“For those candidates that appreciated that sensitive data is a category of personal data the vast majority gained full marks.” “One issue was the use of age as an example of personal data, age is not personal data, but date of birth is.”

Worked example 13 marks

State three examples of personal data.

1
date of birth [1]
2
medical history [1]
3
address (or personal name) [1]

8. Why eSafety is needed

eSafety is about protecting the user and their personal data when using the internet, email, social media and online gaming.

It is not about protecting the computer system. Examiners reported that answers on antivirus, firewalls and spam protect the computer system, not personal data.

A question on the need for eSafety asks why, not how. Correct answers were about protecting personal data and sensitive data, and protecting vulnerable people from predators and stalkers.

Examiner insight

“E-safety relates to the protection of personal data and the user, not the computer system.” “Many candidates wrote about the measures you can take to provide e-safety rather than discussing the need for e-safety.”

Worked example 12 marks

State what eSafety is designed to protect.

1
the user [1]
2
their personal data [1]

9. Staying safe on the internet and by email

On the internet, only use trusted websites recommended by teachers. Use a search engine that only allows access to age appropriate websites.

By email, be aware of the dangers of opening or replying to an email from an unknown person. Be aware of the risks of sending personal identifiable data or images by email.

If the question is about email, answer about email. Examiners reported candidates who wrote only about using the internet.

Examiner insight

“Most gained two marks for stating never to open emails from unknown sources as they may contain viruses.” “This question was an ‘explain’ question which required candidates to make a point and expand upon it.”

Worked example 12 marks

Explain one way a student can minimise the potential dangers of using email.

1
Never open emails from unknown sources [1]
2
as they may contain viruses [1]

12. Staying safe in online gaming

Do not use real names and do not give out personal or financial data. Only communicate with people known to you.

Use a strong password, do not click on unknown links in the game, and play games within the correct age range. Report and block any abuse or cyberbullying.

Worked example 16 marks

Many people play games online. Discuss the ways in which potential dangers of using online gaming can be minimised.

1
Do not share personal information [1]
2
Only communicate with people known to you [1]
3
Use a strong password [1]
4
Do not click on unknown links in the game [1]
5
Play games within correct age range [1]
6
Report and block any abuse / cyberbullying [1]

Recap

Data protection legislation exists so personal data is kept confidential and protected.
Personal data: personal name, address, date of birth, photograph in school uniform, medical history.
Sensitive data is a category of personal data, such as ethnicity or political views.
eSafety protects the user and their personal data, not the computer system.
Internet: trusted websites recommended by teachers, and an age appropriate search engine.
Email: do not open or reply to unknown senders. Take care sending personal data or images.
Social media and gaming: block and report, do not arrange to meet an unknown online contact, no real names, no personal or financial data.

13. Hacking

Hacking is unauthorised access to a computer system. A hacker usually copies data. The data is not removed.

Measures that protect data from hackers include strong passwords and encryption. Describe each measure. Writing only 'password' or 'firewall' does not gain the mark.

Examiner insight

“Many candidates are still writing that one of the consequences of hacking is that data can be stolen. If data is stolen, then it is removed; hacking usually copies data but does not remove it.” “Some candidates thought that a firewall stopped hacking on a system but did not explain this fully and therefore could not gain marks.”

Worked example 14 marks

A company stores customer details on a server. Describe two measures the company can take to protect the data from hackers.

1
Measure 1: use a strong password for each user [1]
2
that uses a range of characters and no personal data, so it is hard to guess [1]
3
Measure 2: encrypt the data [1]
4
so that it is scrambled and meaningless to a hacker who gains access [1]

14. Phishing, pharming, smishing and vishing

In phishing, the victim receives a legitimate-looking email with a link. The link leads to a fake website. In pharming, code placed on the user's computer leads the user to a fake website when the URL is typed in.

Smishing uses a text message. Vishing uses a phone call. Each attack is made with the intention of gaining personal information.

To help prevent phishing, use email filters. To help prevent pharming, use up-to-date anti-malware software. To help prevent vishing, do not answer calls from unknown numbers, block the number and never give personal information to the caller.

Examiner insight

“Weaker candidates mixed up smishing with spam or smishing with emails.” “Some candidates gave good answers like the use of email filters although some candidates wrote spam filters which would not reduce phishing attacks.”

Worked example 14 marks

Describe how phishing and pharming can each take a user to a fake website.

1
Phishing: the user receives a legitimate-looking email [1]
2
the user clicks a link in the email, which leads to the fake website [1]
3
Pharming: code is placed on the user's computer [1]
4
when the user types in the URL, the code leads to the fake website [1]

15. Card fraud

Shoulder surfing is watching a person enter a PIN or card details. Key logging uses software that records the key presses made by the user. Card cloning is making a copy of a card's data.

Name the method. Hackers is too vague an answer, because it does not explain how they would obtain the data.

Examiner insight

“Some candidates are continuing to give vague answers like stealing passwords rather than writing about shoulder surfing.” “Key-logging software will still operate even if a touchscreen is used.”

Worked example 14 marks

Describe how key-logging software and shoulder surfing can each be used to commit card fraud.

1
Key logging: software is installed on the customer's computer [1]
2
it records the key presses as the customer types the card details [1]
3
Shoulder surfing: the criminal stands close to the customer [1]
4
and watches the PIN or card number being entered [1]

16. Viruses and malware

A virus is a piece of software that replicates itself. It is a form of malware. It can corrupt or delete files and stop the user accessing the computer.

Anti-virus software scans files and compares them with a database of known viruses. Anti-malware software protects against a newer, wider range of threats, such as spyware and ransomware. A computer needs both, because some viruses cannot be detected by anti-virus software.

Before use, scan every email attachment and external memory device. Do not download software from sources unknown to you.

Examiner insight

“The question asked candidates to explain what a virus was; some candidates answered what the effect of a virus in a computer was.” “Any answers relating to anti-virus software must also state that the anti-virus software needs to be up-to-date.”

Worked example 14 marks

An ICT student has downloaded a file and notices that he no longer has access to his recycle bin. The school network manager states that this is caused by a computer virus. Describe the methods that the student could use to protect his computer system from viruses.

1
Download anti-virus software [1]
2
Keep the anti-virus software up to date [1]
3
Run a virus scan regularly [1]
4
Do not download or accept software from sources unknown to you [1]

17. Passwords and biometrics

The user id gives access to the system. The password protects the data. A strong password is hard to guess: it uses a range of characters and holds no personal data. It is not given to others.

Biometrics use a body feature such as a fingerprint. The data is unique to the person, is more difficult to forge and the owner has to be present. Two-factor authentication uses two separate checks of identity before access is given.

Examiner insight

“Many candidates knew the User ID was unique, but some also thought that the password was also unique.” “The only common misconception being that biometric data is impossible to forge.”

Worked example 13 marks

Explain how a user id and a password are used to protect the data on a computer.

1
The user id identifies the user and gives access to the system [1]
2
The password protects the data [1]
3
A strong password, with a range of characters and no personal data, is hard to guess [1]

18. Encryption

Encryption is a way of scrambling data so that only authorised users can understand it. It turns plaintext into ciphertext using an algorithm and keys.

Encryption protects data on hard discs, in email, in the cloud and on HTTPS websites. It does not stop hacking. It makes the data meaningless to a hacker who reaches it.

Examiner insight

“Candidates gained marks for encryption key and decryption key as well as explaining that the data was scrambled.” “Some added that it would stop hacking, which it would not do.”

Worked example 14 marks

When data is transmitted over a network, it may need to be protected. One way of protecting data is to use encryption. Explain what is meant by the term encryption.

1
A way of scrambling data [1]
2
Only allows authorised users to understand the data [1]
3
Process of converting human-readable text / plaintext into ciphertext [1]
4
Uses an algorithm / encryption keys / decryption keys [1]

19. SSL and digital certificates

Secure Socket Layer (SSL) secures an internet connection. It encrypts the data sent between a website and a web browser. A website using it shows HTTPS in its address and a locked padlock.

A digital certificate is attached to an email or website. It contains a public key and proves who owns the public key. It makes the public key secure to send over the internet.

Examiner insight

“In the question it asked what was meant by SSL, nearly all candidates wrote it is secure socket layer which was in the question.” “However, some candidates lacked technical precision and merely repeated phrases like adds an extra layer of security without explaining how SSL works.”

Worked example 14 marks

An author has written a large document and is storing it in the cloud. When the document is transmitted to the cloud over the internet it needs to be protected. One way of protecting the document is to use Secure Socket Layer (SSL). Describe the characteristics of Secure Socket Layer.

1
Secures an internet connection [1]
2
It prevents hackers from seeing data [1]
3
Ensures sender and receiver are authentic [1]
4
Encrypts data sent between website and web browser [1]

20. Firewall

A firewall controls the data entering or leaving a computer network. It monitors the traffic into and out of the network. It can block chosen websites and IP addresses.

A firewall does not stop viruses. It does not stop hacking within the network.

Examiner insight

“Most candidates demonstrated very limited understanding of the role of a firewall.” “In order to improve the answering of this question, candidates should understand that a firewall attempts to stop computer systems attacking another computer system or controls the data entering or leaving a computer network.”

Worked example 12 marks

A school network is connected to the internet and uses a firewall. Describe the purpose of the firewall.

1
It monitors the traffic coming into and going out of the network [1]
2
It blocks traffic from chosen websites or IP addresses [1]

Recap

Hacking = unauthorised access. Data is usually copied, not removed.
Phishing = legitimate-looking email with a link to a fake website. Pharming = code on the user's computer. Smishing = text message. Vishing = phone call.
Card fraud: shoulder surfing, card cloning, key logging.
Anti-virus must be kept up to date. Anti-malware covers a newer, wider range of threats. Scan attachments and downloads.
User id gives access, password protects the data. Biometrics are unique.
Encryption turns plaintext into ciphertext using keys. SSL encrypts data between browser and server.
A firewall monitors traffic into and out of a network.

End-of-chapter exercise

Test yourself on the whole chapter. Work through these before moving on.

A drink is spilled onto a computer that is switched on. Name the safety issue for the user.1 mark
State two causes of fire in a computer room.2 marks
A cable runs across the floor of an office. State the safety issue and one way to prevent it.2 marks
Describe two ways an employee could be electrocuted in an office.2 marks
A room is full of computers joined by cables. Give two ways to prevent people tripping over the cables.2 marks
A pupil writes this rule: ‘Do not take drinks into the computer room.’ Rewrite the rule so that it earns credit, and name the safety issue it prevents.2 marks
A technician plugs a computer, a monitor, a printer, a scanner and a heater into one socket. Explain the safety issue and how to prevent it.3 marks
A shop stands a heavy laser printer on a thin plastic tray above the till. Describe the safety issue and one way to prevent it.3 marks
A library sets up a help desk in its entrance hall. A laptop, a label printer and a lamp are plugged into one socket by a lead that crosses the hall. A volunteer lists three safety issues. For each entry, state what is wrong with it and write a correct safety issue in its place. | Entry | What the volunteer wrote | | --- | --- | | A | Trailing lead: visitors could be led to a fake website. | | B | Spilt drink: the laptop would stop working. | | C | The socket: do not plug in too many devices. |6 marks
A sports club turns a store room into a control room for its scoreboard. Four computers, two large screens and a fan are all plugged into one socket. The lead from the socket lies across the doorway. One large screen stands on a pile of cardboard boxes. Staff keep cups of tea beside the keyboards and say the screens give them headaches. The club cannot fit any more sockets. Identify four different safety issues in this room, with the cause of each, and give a prevention for each that the club is able to use.8 marks
Give one reason why data protection legislation is required.1 mark
Which two of these are personal data? Age; date of birth; photograph in school uniform; the school's opening hours.2 marks
A student gives 'bank account details' as an example of personal data. Write a more precise answer.1 mark
Explain why a student's personal data must be kept confidential.2 marks
A student says: 'Sensitive data and personal data are the same thing.' Explain what is wrong with this.2 marks
Ali says: 'eSafety means installing antivirus software and a firewall.' Explain why this does not describe eSafety.2 marks
Mia receives an email from an unknown person. It asks her to reply with a photograph of herself in school uniform and her home address. State two things Mia should not do, and give a reason for one of them.3 marks
State three different ways a student can minimise the risks of using social media. Do not mention passwords.3 marks
A chess club for players aged 11 to 16 runs an online tournament with a chat window. The organiser drafts three safety instructions: 1. Install antivirus software. 2. Use your full name as your username so opponents know who you are. 3. Pay the entry fee by typing your card number into the chat. For each instruction, explain why it does not keep the players eSafe and write a better instruction.6 marks
A sports club for teenagers has a social media group. A volunteer posts a team photograph of the players in school uniform. The caption gives each player's full name, age and date of birth, and one player's medical history. Another member replies using abusive language. (a) Identify the four items of personal data in the post. (b) Explain why the post should not have been made. (c) The club decides to employ a person to monitor the group. Explain why this is necessary, using this post and the reply.7 marks
State what is meant by hacking.1 mark
Message A is an email with a link to a website that looks like a bank's website. Message B is a text message that asks the reader to ring a number. Name the type of attack in each.2 marks
A criminal stands close behind a customer at a cash machine and sees the PIN being typed. Name this method of card fraud and describe it.2 marks
Distinguish between a user id and a password.2 marks
A user types her card number on a touchscreen and says that this means key-logging software cannot record it. Is she correct? Explain your answer.2 marks
Give two reasons why a fingerprint scan is more secure than a password.2 marks
A user called Sam, born in 1990, uses the password Sam1990. Give two reasons why this is a weak password and state one way to make it stronger.3 marks
A user downloads a file from a website. Describe two actions the user can take to reduce the risk of the file infecting the computer.4 marks
A patient of a dental surgery receives a phone call. The caller says he works at the surgery and asks her to confirm her card number. Later she types the surgery's correct web address into her browser, but a copy of the surgery's website opens and asks for her password. The receptionist tells her that both attacks are phishing. Name each attack, give a reason for each name, and state one precaution against each.6 marks
A hacker gains access to the customer records of a vet's practice. The manager writes a report containing four statements. Statement 1: The hacker stole our customer records. Statement 2: Our firewall should have stopped the hacker, because a firewall stops hackers and viruses. Statement 3: We will encrypt the records, which will stop hacking. Statement 4: Staff will use a fingerprint to log in, because a fingerprint is impossible to forge. Explain what is wrong with each statement and give the correct fact.8 marks

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Hardware and software Input devices and their uses Storage devices and media Networks Microprocessor-controlled devices Communication

Read the notes

1. Electrocution#

2. Fire#

3. Tripping over trailing cables#

4. Heavy equipment falling#

5. Safety, not health or security#

6. Data protection#

7. Personal data and sensitive data#

8. Why eSafety is needed#

9. Staying safe on the internet and by email#

10. Staying safe on social media#

11. Monitoring a social media group#

12. Staying safe in online gaming#

13. Hacking#

14. Phishing, pharming, smishing and vishing#

15. Card fraud#

16. Viruses and malware#

17. Passwords and biometrics#

18. Encryption#

19. SSL and digital certificates#

20. Firewall#

End-of-chapter exercise

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Chapter at a Glance

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Related chapters

1. Electrocution

2. Fire

3. Tripping over trailing cables

4. Heavy equipment falling

5. Safety, not health or security

6. Data protection

7. Personal data and sensitive data

8. Why eSafety is needed

9. Staying safe on the internet and by email

10. Staying safe on social media

11. Monitoring a social media group

12. Staying safe in online gaming

13. Hacking

14. Phishing, pharming, smishing and vishing

15. Card fraud

16. Viruses and malware

17. Passwords and biometrics

18. Encryption

19. SSL and digital certificates

20. Firewall