Back to 课程

Computer Science GCES OCR

0% Complete
0/0 Steps
  1. Cpu Architecture Performance And Embedded Systems Ocr
    5 主题
  2. Primary And Secondary Storage Ocr
    6 主题
  3. Data Storage And Compression Ocr
    12 主题
  4. Networks And Topologies Ocr
    6 主题
  5. Wired And Wireless Networks Protocols And Layers Ocr
    6 主题
  6. Identifying And Preventing Threats To Computer Systems And Networks Ocr
    2 主题
  7. Operating Systems And Utility Software Ocr
    2 主题
  8. Ethical Legal Cultural And Environmental Impact Ocr
    2 主题
  9. Computational Thinking Searching And Sorting Algorithms Ocr
    3 主题
  10. Designing Creating And Refining Algorithms Ocr
    5 主题
  11. Programming Fundamentals And Data Types Ocr
    5 主题
  12. Additional Programming Techniques Ocr
    7 主题
  13. Defensive Design And Testing Ocr
    6 主题
  14. Boolean Logic Diagrams Ocr
    2 主题
  15. Programming Languages And Integrated Development Environments Ides Ocr
    3 主题
  16. The Exam Papers Ocr
    2 主题
  17. Structuring Your Responses Ocr
    3 主题
课 Progress
0% Complete

Exam code:J277

Encryption

What is encryption?

  • Encryption is a method of scrambling data before being transmitted across a network in order to protect the contents from unauthorised access

  • While encryption is important on both wired and wireless networks, it’s even more critical on wireless networks due to the data being transmitted over radio waves, making it easy to intercept

How is wireless data encrypted?

  • Wireless networks are identified by a ‘Service Set Identifier’ (SSID) which along with a password is used to create a ‘master key

  • When devices connect to the same wireless network using the SSID and password they are given a copy of the master key

  • The master key is used to encrypt data into ‘ciphertext‘, before being transmitted

  • The receiver uses the same master key to decrypt the cipher text back to ‘plaintext‘ 

  • To guarantee the security of data, the master key is never transmitted

  • Without it, any intercepted data is rendered useless

  • Wireless networks use dedicated protocols like WPA2 specifically designed for Wi-Fi security

wireless-encryption

How is wired data encrypted?

  • Wired networks are encrypted in a very similar way to a wireless network, using a master key to encrypt data and the same key to decrypt data

  • Encryption on a wired network differs slightly as it is often left to individual applications to decide how encryption is used, for example HTTPS

Worked Example

A bank does not use encryption when data is transmitted through the network.

Give two reasons why the bank should use encryption [2]

How to answer this question

  • Answer must be ‘why’ the bank should use encryption and NOT just what encryption is. Give examples in your answer

Answer

  • Customer data cannot be understood if intercepted // The data will be meaningless

  • So that only authorised users can access the confidential material // protect confidential/personal/user/bank data

  • To follow legislation/Data Protection Act

Responses

您的邮箱地址不会被公开。 必填项已用 * 标注