Page 230 - DCAP403_Operating System

Unit 11: System Security

11.13 Self Assessment Notes

State whether the following statements are true or false:

1. Physical computer security involves tangible protection devices, such as locks, cables,
fences, safes, or vaults.

2. Confidentiality is also known as secrecy or privacy.

3. Resource attacks are the first category of network security threats.
4. DoS (Denial-of-Service) attacks are probably the nastiest, and most difficult to address.

5. Websites that use an encrypted connection use something called SSL (Secure Sockets Layer)
to secure the information going back and forth.

Fill in the blanks:
6. ......................... authentication systems authenticate a user based on the knowledge or
possession of a cryptographic key.

7. Encryption and ......................... generally require the use of some secret information,
referred to as a key.
8. ......................... can be used to sign or encrypt e-mail messages with the mere click of the
mouse.
9. Hash functions, also called ......................... and one-way encryption
10. Intrusion Prevention Systems (IPSs) evolved in the late ......................... .

11.14 Review Questions

1. What do you mean by system security?

2. Explain security problem.
3. Describe program threats.
4. Write short note on “denial of service” attack.
5. What do you mean by hashing?

6. Describe “Pretty Good Privacy” concept.
7. Explain user authentication process in detail.
8. How will you implement security defenses? Explain
9. Describe fi rewall concept.
10. Describe various types of intrusion prevention system.

Answers: Self Assessment

1. True 2. True 3. False 4. True

5. True 6. Cryptographic 7. decryption 8. PGP
9. message digests 10. 1990s

LOVELY PROFESSIONAL UNIVERSITY 223