Assignment 2

Total of 50 marks. Answer the following questions. Show your work for any calculations.

Treat this assignment as an open-book individual exam. You may consult any of your class notes or other books or documents, paper or electronic. However, you may NOT discuss questions or share answers with any other person until after the assignment is due.

  1. How much disk space is taken by a minute-long uncompressed digital stereo audio file sampled at 11 KHz, 16 bits per sample? [2]
  2. What do Manchester and Differential Manchester encoding have in common? Why do they not just use a high voltage for 1 and a low voltage for 0? [2]
  3. What are both 4 bit/5 bit and 5 bit/6 bit encoding designed to prevent? [1]
  4. Give three differences between baseband and broadband communication. [3]
  5. Give two advantages of conducted media and two advantages of radiated media. [4]
  6. What is the physical difference among the different types of radiated signals? Which types of radiation tend to have the highest transmission speeds? [2]
  7. What is a hot swappable component? What types of server components are most likely to be hot swappable? [3]
  8. What are three specific features you should look for when buying a network card? [3]
  9. List three components or devices that are particularly important to the reliability of a server and therefore the network. [3]
  10. What are the meanings of the three parts of the names of popular LAN standards such as 10baseT and 1000baseSX? [3]
  11. If NICs using p-persistent CSMA may transmit every 20 microseconds with probability 0.2, what is the average wait before transmitting? [1]
  12. In CSMA/CD binary exponential backoff,
    If a collision is detected, the NIC will wait 0 to 1 slot times before transmitting.
    If another collision occurs, the NIC will wait 0 to 3 slot times.
    If a third collision occurs, how long will the NIC wait? [1]
  13. If collision detection requires listening and re-transmission, why is it used more often than collision avoidance? [2]
  14. What type of media access should be used for a small network with low performance requirements? [1]
  15. Why does a token bus have more complex token-passing algorithms than a token ring? [1]
  16. What is the purpose of a MAC address? [1]
  17. Why must IEEE 803.2 frames be at least 64 bytes? [1]
  18. What part of the network software allows you to read or write to a file on the network as if it were on the local PC? [1]
  19. Give an advantage of disk mirroring over RAID and two advantages of RAID over mirroring. [3]
  20. A system has full backups every week at the end of the day on Sunday.
    At the end of each of the remaining six days, the system has a differential or incremental backup.
    If a user discovers her file missing on Friday, at most how many backups would need to be consulted to find the file
    1. if differential backups were used?
    2. if incremental backups were used? [2]
  21. What type of site licence would be best to buy for
    1. an infrequently used software package to be installed on 100 computers?
    2. a heavily used software package in a large building with a variable number of computers? [2]
  22. Name the database of network objects used in
    1. Novell NetWare 3.x
    2. Novell NetWare 4.x
    3. Windows 2000 [3]
  23. Which networking protocol is built in and used by default in
    1. Novell NetWare?
    2. Windows 9x/NT?
    3. UNIX? [3]
  24. List two ways that users and computers are grouped in Windows. [2]