CO1630 Communication Network Security M.E Question Bank : niceindia.com

Name of the College : Noorul Islam College of Engineering
University : Anna University
Degree : M.E Communication Systems
Department : Electronics and Communication Engineering
Subject Code/Name : CO 1630 – Communication Network Security
Document Type : Question Bank
Website : niceindia.com

Download Model/Sample Question Paper : https://www.pdfquestion.in/uploads/niceindia.com/3109-CO1630-Communication-Network-Security.pdf

NICE Communication Network Security Question Paper

Unit-1 : Symmetric Ciphers
1. Define security attack ? :
Any pattern that compromise the security of information owned by an organization is called as the security attack.

Related : Noorul Islam College of Engineering XCS471 Principles of Management M.Sc Question Bank : www.pdfquestion.in/3138.html

2. Define security mechanism ? :
A mechanism that is designed to detect, prevent or recover from security attacks.

3. What do you mean by security service ? :
A service that enhances the security of data processing systems and information transfer of an organization.

4. What are the classifications of security services ? :
(a). Confidentiality
(b). Authentication
(c). Integrity
(d). Non-repudiation
(e). Access control
(f). Availability

5. What do you mean by confidentiality ? :
This ensures that information in a computer system and transmitted information are accessible only for reading by authorized parties.

6. Define authentication ? :
This ensures that origin of a message or electronic document is correctly identified with an assurance that identity is not false.

7. Define integrity ? :
This ensures that every authorized parties are able to modify computer system assets and transmitted information.

8. What do you mean by non-repudiation ? :
This means that neither the sender or the receiver message be able to deny the transmission.

9. What do you mean by access control ? :
Access control requires that access to information resources may be controlled by the target system.

10. What are the types of security attacks ? :
(a). Interruption
(b). Interception
(c). Modification
(d). Fabrication

11. What do you mean by interruption ? :
An asset of system is destroyed or becomes unusable. This is an attack on availability.

12. What do you mean by interception ? :
An unauthorized party gains access to an asset. This is an attack on confidentiality.

13. What do you mean by modification ? :
An unauthorized party not only gains access to but tampers with an asset. This is an attack on integrity.

14. What are the types of attacks ? :
(a). Active attacks
(b). Passive attacks

15. Define cryptography ? :
Many schemes used for encryption constitute the access of study known as cryptography.

16. What do you mean by cryptanalysis ? :
The process of attempting to discover plaintext or encryption key or both plaintext and encryption key is known as cryptanalysis.

17. What do you mean by steganography ? :
Steganography is the process of concealing the existence of message. It is an encryption process.

18. What are the steganographic methods ? :
(a). Character marking
(b). Invisible ink
(c). Pin punctures
(d). Type writer ribbon correction.

19. Name the techniques involved in classical encryption ? :
(a). Substitution techniques
(b). Transposition techniques
(c). Rotor machines

20. What do you mean by stream cipher ? :
A stream cipher is that one encrypts data stream one bit or one byte at a time.
eg : vernam cipher

21. What do you mean by block cipher ? :
Here a block of plaintext is treated as a whole to produce a ciphertext block of equal length.

22. What do you mean by conventional encryption ? :
Conventional encryption also referred to as symmetric encryption or single key encryption. The security of conventional encryption depends on several factors, such as the encryption algorithm and the secrecy of the key.

23. When do we say an encryption scheme is unconditionally secure ? :
An encryption scheme is unconditionally secure if the ciphertext generated by the scheme does not contain enough information to determine uniquely the corresponding plaintext, no matter how much ciphertext is available.

24. When do we say an encryption scheme is computationally secure ? :
An encryption scheme is computationally secure if they meet two criterias.
(a). The cost of breaking the cipher exceeds the value of the encrypted information.
(b). The time required to break the cipher exceeds the useful time of the information.

25. What is the strength of DES ? :
The strength of DES depends on two factors.
(a). The use of 56-bit keys
(b). the nature of the DES algorithm.