Describe protection measures including strong passwords, firewalls, encryption, antivirus software and user access levels

What this dot point is asking

SEAB wants you to describe the main measures used to protect a network and its data: strong passwords, firewalls, encryption, antivirus software and user access levels. The central idea is that no single measure is enough, so good security uses several layers together, each defending against different threats.

The answer

Strong passwords and authentication

A strong password is long, mixes upper and lower case letters, numbers and symbols, and is not a common word or reused across accounts. This makes it hard to guess or crack. Two-factor authentication (2FA) adds a second check, such as a code sent to a phone, so a stolen password alone is not enough to get in.

Firewalls

A firewall monitors and controls the data passing between a network and the outside world. Using a set of rules, it blocks unwanted or suspicious traffic and allows trusted traffic. It acts as a barrier that helps prevent unauthorised access from the internet.

Encryption

Encryption scrambles data using a key so that it is unreadable to anyone without that key. It protects data both in transit (such as over HTTPS) and at rest (stored on a disk). If encrypted data is intercepted or stolen, the attacker sees only meaningless characters.

Antivirus software

Antivirus (anti-malware) software scans files and activity to detect, block and remove malware such as viruses and worms. Kept up to date, it recognises new threats and helps stop infections spreading across a network.

User access levels

User access levels give different users different permissions. A student might only open their own work, a teacher edit class records, and an administrator manage accounts. This follows the principle of least privilege: each user can access only what they need, which limits misuse and contains the damage if one account is compromised.

Other measures

• Regular backups so data can be restored after loss or a ransomware attack.
• Software updates to fix security weaknesses.
• User training so people recognise phishing and other tricks.

Layered defence

Each measure addresses different threats: passwords and access levels guard accounts, firewalls filter traffic, encryption protects data, and antivirus fights malware. Using them together gives defence in depth, so if one layer fails, others still protect the network.

Examples in context

Example 1. A hospital records system. Patient records are encrypted and protected by user access levels, so a receptionist sees only appointments while a doctor sees medical notes. If a laptop is stolen, the encryption keeps the records unreadable, and access levels limit what any single account can reach.

Example 2. A home router. A home network is protected by changing the default router password to a strong one, keeping the firewall on, and enabling Wi-Fi encryption. Together these stop neighbours or passers-by from joining the network or reading its traffic, a small-scale layered defence.

Try this

Q1. State what a firewall does. [2 marks]

• Cue. It monitors and filters traffic between a network and the outside, blocking unwanted traffic and allowing trusted traffic by rules.

Q2. Explain why user access levels improve security. [2 marks]

• Cue. They give each user only the permissions they need, so misuse is limited and a compromised account exposes less data.

Q3. Give one reason a password should not be reused across accounts. [2 marks]

• Cue. If one account is breached, a reused password would let the attacker access all the other accounts too.