Network Security

What Network Security covers

Network Security is examined in J277/01, Computer systems. It covers malware, social engineering and brute-force attacks, denial of service, data interception and SQL injection and identifying and preventing vulnerabilities.

The 3 subtopics

Each one has its own page.

• Malware, social engineering and brute-force attacksViruses, worms, trojans, ransomware and spyware, social engineering, phishing and blagging, people as the weak point, and brute-force attacks with worked password combinations.Open →
• Denial of service, data interception and SQL injectionDenial of service and DDoS attacks, botnets, data interception and theft, and how SQL injection exploits a poorly written website.Open →
• Identifying and preventing vulnerabilitiesPenetration testing, anti-malware software, firewalls, user access levels, strong passwords, encryption and physical security, and what each prevention method limits.Open →

What you need to know

Answer each one before you reveal it.

Take Network Security further

The same content, four other ways.

Commonly confused

Pairs that lose marks when they are blurred together.

• Virus vs Worm

  Virus: malicious code that attaches to a file and spreads when that file is run or shared. Worm: malicious code that copies itself across a network with no host file or user action.

• Ransomware vs Spyware

  Ransomware: malicious code that locks a victim's files and demands payment to unlock them. Spyware: malicious code that secretly records what a user does and sends it to an attacker.

• Phishing vs Blagging

  Phishing: sending fake messages that look genuine to trick people into revealing details. Blagging: inventing a believable story, often by phone, to persuade someone to hand over information.

Questions from this topic

Each one with the model answer underneath.

1. 1

   State three threats that an attack can pose to a computer system.

   Model answer

   An attack can steal confidential or personal data. An attack can corrupt or delete files. An attack can stop a system working, costing the owner money and reputation.

2. 2

   Define the term malware.

   Model answer

   Malware is malicious software written to damage, disrupt or gain unauthorised access to a computer system. Malware is usually installed without the user's knowledge.

3. 3

   What is a computer virus?

   Model answer

   A virus is malware that attaches itself to a program or file. A virus spreads when the infected file is run or shared, and can corrupt or delete data.

4. 4

   How does a worm differ from a virus?

   Model answer

   A worm copies itself and spreads across a network on its own. A worm needs no host file and no action from the user.

5. 5

   What is a trojan?

   Model answer

   A trojan is malware disguised as useful or legitimate software. The user installs the trojan willingly, and the hidden code then carries out harmful actions.

6. 6

   What does ransomware do?

   Model answer

   Ransomware encrypts the files on a victim's computer so they cannot be opened. The attacker then demands payment in exchange for the decryption key.

What is inside Levo

Six ways to work the same material.

Network Security revision questions

What does Network Security cover in OCR GCSE Computer Science?

3 subtopics: malware, social engineering and brute-force attacks, denial of service, data interception and sql injection and identifying and preventing vulnerabilities. Each one has its own page with questions and model answers.

How is Network Security organised?

By the OCR J277 specification, subtopic by subtopic, so it matches the order you are taught it in.