Year 10 · ICT · Autumn 2
Networks; layout and styles · Lesson 3 of 5
Security on a network
Theory4.2 Network issues and communication
Year 10 · ICT · Networks; layout and styles · Lesson 3 of 5
You will learn to
- Explain why data sent over a network must be kept secure.
- Compare strong and weak passwords.
- Describe authentication methods: passwords, biometrics, cards, physical and electronic tokens, and zero login.
- Explain how anti-malware software protects a network.
Year 10 · ICT · Networks; layout and styles · Lesson 3 of 5
Success criteria
You have got it when you can say:
- I can rank three passwords from weakest to strongest and say why.
- I can give one advantage and one disadvantage of biometrics.
- I can explain how an electronic token adds a second check to a password.
Year 10 · ICT · Networks; layout and styles · Lesson 3 of 5
Retrieval starter
Questions from before. Write your answers, then show them.
- Last lesson
A section break lets you…
A Spell checkB Change orientation or columns part-way through a documentC Add a picture
B. Change orientation or columns part-way through a document
- Last unit
A touch screen that senses the electricity in your finger is…
A CapacitiveB Infra-redC Resistive
A. Capacitive
- Earlier this unit
A gutter is…
A The page borderB A footerC The gap between columns
C. The gap between columns
Year 10 · ICT · Networks; layout and styles · Lesson 3 of 5
Key words (1 of 3)
- Network
- Two or more devices connected so they can share data and resources.
- NIC
- Network interface card: hardware that connects a device to a network.
- IP address
- An address that identifies a device on a network or the internet.
- LAN
- Local area network: covers one building or site.
Year 10 · ICT · Networks; layout and styles · Lesson 3 of 5
Key words (2 of 3)
- Authentication
- Proving a user is who they say they are.
- Biometrics
- Using unique body features such as fingerprints for authentication.
- One-time password
- A code that works only once, made by a token.
- Zero login
- Authentication without typing, using biometrics and behaviour.
Year 10 · ICT · Networks; layout and styles · Lesson 3 of 5
Key words (3 of 3)
- Anti-malware
- Software that detects, quarantines and removes malicious software.
The explanation · step 1 of 7
Security of data transfer
Data on a network can be intercepted, changed or stolen. Networks also spread malware quickly.
Authentication means proving that a user is who they say they are, before they get access.
Common protections: user IDs and passwords, firewalls, encryption of data being sent, and anti-malware software.
The explanation · step 2 of 7 · part 1 of 3
Strong and weak passwords
A weak password is short or easy to guess: a name, a birthday, a word from the dictionary, `123456` or `password`.
A strong password is long and mixes upper-case letters, lower-case letters, numbers and symbols. It is not a real word and is not linked to the user.
Each extra character multiplies the number of possible passwords. So length matters most. Type passwords into the checker and watch the time to crack change.
The explanation · step 2 of 7 · part 2 of 3
Strong and weak passwords (continued)
The explanation · step 2 of 7 · part 3 of 3
Strong and weak passwords (continued)
A strong password is still unsafe if it is reused on many sites, written on a sticky note, or never changed after a data breach.
There is something to try for this step in the IGCSE library.
The explanation · step 3 of 7 · part 1 of 2
Passwords and biometrics
Passwords are the most common method. They are cheap and easy, but can be guessed, forgotten, seen by shoulder surfing or stolen by spyware.
Biometrics use a unique part of a person's body or behaviour: fingerprint, face, iris or retina, voice or handwriting.
The explanation · step 3 of 7 · part 2 of 2
Passwords and biometrics (continued)
| Biometric | Advantage | Disadvantage |
|---|---|---|
| Fingerprint | Quick and cheap; unique to each person | Dirty or cut fingers may not be recognised |
| Face recognition | No contact needed | Lighting, glasses, beards or ageing can cause errors |
| Iris / retina scan | Very accurate and very hard to fake | Expensive; retina scanning is intrusive |
| Voice recognition | Works over the phone; no extra hardware on a phone | Colds and background noise cause errors; can be recorded and replayed |
Biometrics are more secure than passwords because a body feature cannot be forgotten, shared or easily guessed.
The explanation · step 4 of 7 · part 1 of 3
Cards and tokens
A magnetic stripe card holds data such as a staff ID on its stripe. It is swiped to open doors. Cheap, but easy to copy and damaged by magnets.
A smart card has a chip that stores and processes data, often with an RFID antenna. It is harder to copy and can hold more data. Often used with a PIN.
A physical token is a small device that shows a one-time password (OTP). Some need the user's PIN first. Banks use them for online banking.
The explanation · step 4 of 7 · part 2 of 3
Cards and tokens (continued)
An electronic token is software, usually an app on a phone, that creates a one-time code or approves a log-in. Codes change every 30 to 60 seconds, so a stolen code is soon useless.
The explanation · step 4 of 7 · part 3 of 3
Cards and tokens (continued)
A token's code is a one-time password. Say why it helps: even if it is intercepted, it cannot be used again.
The explanation · step 5 of 7
Zero login
Zero login is a way of authenticating without typing anything. The system recognises the user from biometrics and behaviour, such as how they hold the phone, how they type and where they usually are.
Advantage: very convenient, and nothing to forget.
Disadvantage: the system collects lots of personal data, users may not know they are being tracked, and it is harder to tell how secure it is.
The explanation · step 6 of 7 · part 1 of 2
Anti-malware
Malware is software designed to harm a computer or steal data, such as viruses, spyware and ransomware.
Anti-malware software (including anti-virus) scans files and emails, compares them with a database of known malware signatures, and watches for suspicious behaviour.
Infected files are quarantined (isolated so they cannot run) or deleted. The software must be updated regularly so it knows about new malware.
The explanation · step 6 of 7 · part 2 of 2
Anti-malware (continued)
On a network, one infected computer can infect all the others, so every device needs up-to-date anti-malware.
The explanation · 1 more step
More on the lesson page
The lesson page has the rest of the explanation, step by step:
- Electronic conferencing
Year 10 · ICT · Networks; layout and styles · Lesson 3 of 5
Quick quiz · 1 of 3
Spacing 'after' a paragraph is…
- A The space below it before the next paragraph
- B The margin
- C The line spacing
A. The space below it before the next paragraph
Spacing before and after are separate settings.
Year 10 · ICT · Networks; layout and styles · Lesson 3 of 5
Quick quiz · 2 of 3
Applying a style instead of formatting by hand means…
- A It is slower
- B Changing the style changes every heading at once
- C It only works in Word
B. Changing the style changes every heading at once
Consistency and speed.
Year 10 · ICT · Networks; layout and styles · Lesson 3 of 5
Quick quiz · 3 of 3
.csv is…
- A Comma-separated values: a generic data format
- B A picture
- C A web page
A. Comma-separated values: a generic data format
Any spreadsheet or database can open it.
Year 10 · ICT · Networks; layout and styles · Lesson 3 of 5
Exit ticket
Answer on paper before you go. Then check.
A .pdf is used because…
A It looks the same on every computerB Anyone can edit itC It is the smallest file
A. It looks the same on every computer Layout and fonts are fixed inside the file.
Zip compression is…
A LossyB LosslessC Neither
B. Lossless Every byte comes back when you unzip.