Quiz - 02 Reliability in computer systems PDF

Teach Computer Science Reliability in computer systems teachcomputerscience.co m Quiz 1. Which of the following is a security critical system? A. Military system B. Unmanned train system C. Stock-trading system 2. Which of th...

Teach Computer Science Reliability in computer systems teachcomputerscience.co m Quiz 1. Which of the following is a security critical system? A. Military system B. Unmanned train system C. Stock-trading system 2. Which of the following location is NOT suitable for storing backup disk? A. Administrator’s personal computer B. Separate server C. Over the internet using cloud technology 3. What is disaster recovery? A. The process of duplicating critical parts of a computer system. B. The process of saving back-up in a fire proof location. C. The process of getting back lost data from backup after a system failure 4. What is the best time for an online airline ticketing system to backup its files? A. At lunchtime when many customers access the website. B. Every morning when the customers start accessing. C. Late at night when very few customers access the system. teachcomputerscience.co m 5. Which of the following explains the function of RAID? A. Redundant hardware to store redundant data. B. Redundant software C. Redundant power supply 6. Why do programmers use conservative technique to model critical systems? A. The strength and weakness of the technique is known. B. The response of system is unpredictable. C. Higher efficiency. 7. Why is it important to backup often? For example: every day rather than every week A. It will cost more to backup every week. B. The more the time interval between the backups, the more the data is lost. C. It is ok to miss a few backups if they are done more frequently. 8. What is a fault tolerant system? A. A system that avoids all occurrences of failures. B. A system that operates properly even if it undergoes one or more failures. C. A system that may fail completely in case of a failure. teachcomputerscience.co m 9. Which of the following describes a system that fails gracefully? A. A computer that shuts down abruptly. B. A word document creates a recovery emergency copy as it crashes. C. A presentation crashes while a user is on operation but does not create a restore document. 10. What steps are taken to prevent software failure of a system? A. Software is installed in a drive occupying less memory. B. Redundant software is installed. C. In case of failure, software is uninstalled and installed again. 11. Which of the following is true about data backup? A. Backup takes place whenever a new data is entered. B. Back-up is accessible in internet by all employees. C. Backup is useful when the data is accidentally overwritten. 12. What is the function of extra checks added in case of defensive programming? A. Warns the user in case the program is not working in the desired manner. B. Stores a redundant program that is used in case of failure of current program. C. Even though the program works correctly, it warns the user if it is inefficient. teachcomputerscience.co m 13. What is the difference between hardware and software? A. Hardware is tangible, but software is intangible. B. Hardware is permanent, but software is temporary. C. Hardware is reliable, but software is unreliable. 14. How is the reliability factor, percentage of time calculated? A. Calculating amount of time the system has operated without reporting any problems. B. Calculating percentage of time for which the system spends out of action. C. Calculating percentage of time for which the service was available and operational during a particular month. 15. How is the mean of numbers calculated? A. Add all the numbers. B. Add up all the numbers, then divide by how many numbers there are. C. Add up all the numbers, then multiply by how many numbers there are. 16. Which of the following represents the time duration in which the system is expected to continue its operation before shutting down due to a failure? A. Mean time between failures. B. Downtime C. Mean time to failure teachcomputerscience.co m 17. Which of the following represents the amount of time the system has operated without reporting any problems? A. Percentage of time B. Mean time between failures C. Number of hours 18. What is a life critical system? A. A system whose failure will result severe damage to equipment B. A system whose failure will result in death C. A system whose failure will result in loss D. All of the above 19. How can you improve reliability of a system? A. Thorough design adhering to the standards B. By connecting the system to internet C. By coding in Python D. Using a variety of software applications teachcomputerscience.co m Answers Question Question Answer Answer Number Number 1 A 14 C 2 A 15 B 3 C 16 C 4 C 17 C 5 A 18 D 6 A 19 A 7 B 8 B 9 B 10 B 11 C 12 A 13 A teachcomputerscience.co m