Sixth Semester · BCA 353
Cryptography and Network Security Notes
A dedicated BCA World study page for this subject, aligned to the TU BCA 2025 curriculum units.
How to study this subject
For each unit, learn the definition, understand the process, practise one example, and finish by explaining the concept in your own words. Use the model questions after completing the unit notes.
Unit-by-unit notes
01
Security goals, threats, vulnerabilities, and risk management
Revise the definition, components, workflow, common examples, and practical use of security goals, threats, vulnerabilities, and risk management. Relate it to a small problem or case study from Cryptography and Network Security.
- Define the key terms and identify the main components.
- Draw or describe the workflow, architecture, formula, or process where relevant.
- Connect the idea to a practical BCA example and revise common advantages or limitations.
02
Classical and modern symmetric cryptography
Revise the definition, components, workflow, common examples, and practical use of classical and modern symmetric cryptography. Relate it to a small problem or case study from Cryptography and Network Security.
- Define the key terms and identify the main components.
- Draw or describe the workflow, architecture, formula, or process where relevant.
- Connect the idea to a practical BCA example and revise common advantages or limitations.
03
Public-key cryptography, digital signatures, and key management
Revise the definition, components, workflow, common examples, and practical use of public-key cryptography, digital signatures, and key management. Relate it to a small problem or case study from Cryptography and Network Security.
- Define the key terms and identify the main components.
- Draw or describe the workflow, architecture, formula, or process where relevant.
- Connect the idea to a practical BCA example and revise common advantages or limitations.
04
Hash functions, authentication, certificates, and secure protocols
Revise the definition, components, workflow, common examples, and practical use of hash functions, authentication, certificates, and secure protocols. Relate it to a small problem or case study from Cryptography and Network Security.
- Define the key terms and identify the main components.
- Draw or describe the workflow, architecture, formula, or process where relevant.
- Connect the idea to a practical BCA example and revise common advantages or limitations.
05
Network defence, firewalls, intrusion detection, and incident response
Revise the definition, components, workflow, common examples, and practical use of network defence, firewalls, intrusion detection, and incident response. Relate it to a small problem or case study from Cryptography and Network Security.
- Define the key terms and identify the main components.
- Draw or describe the workflow, architecture, formula, or process where relevant.
- Connect the idea to a practical BCA example and revise common advantages or limitations.
Model questions for BCA 353
Short answerDefine security goals, threats, vulnerabilities, and risk management and mention two important uses.
Define security goals, threats, vulnerabilities, and risk management and mention two important uses. Answer using a definition, structured explanation, relevant example, and conclusion.
Long answerExplain classical and modern symmetric cryptography with a suitable diagram, example, or step-by-step method.
Explain classical and modern symmetric cryptography with a suitable diagram, example, or step-by-step method. Answer using a definition, structured explanation, relevant example, and conclusion.
Practical / applicationApply public-key cryptography, digital signatures, and key management to solve a small Cryptography and Network Security problem. State your assumptions and conclusion.
Apply public-key cryptography, digital signatures, and key management to solve a small Cryptography and Network Security problem. State your assumptions and conclusion. Answer using a definition, structured explanation, relevant example, and conclusion.