CS320 Exam 1 Guide

Shown below is a list of possible questions that may appear on the CS320. Examination 1. You will be required to answer each of the questions in 100 words or less.

The chapters from Comer that will be covered include 1, 2, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 15, 16, 17, 18, 19, 20, 21, 22, 24.

  1. Draw the wave-form diagram that results when the word cat is sent in ASCII across an RS-232 connection.
  2. Briefly describe what RS-232 is. Where is it used?
  3. What is the purpose of a hub? A MAU?
  4. Describe the advantages and disadvantages of point to point communications links.
  5. Describe the important elements of a token ring network.
  6. Describe how binary exponential backoff is used.
  7. What is the difference between full duplex and half duplex communications.
  8. How much information can be carried by a T1 line?
  9. What is propagation delay? Describe it in the context of other types of delays.
  10. State briefly the uses of twisted pair, coax and fiber optic cabling in network communications.
  11. What are some common techniques used for error correction on computer networks.
  12. What is the purpose of a carrier wave?
  13. What type of wiring scheme is a BNC connector used in? What the advantages and disadvantages to other connectors?
  14. Describe what CMSA is. Why is it necessary?
  15. Define baud rate.
  16. Compare ring, bus and star LAN topologies.
  17. What is a collision on a network?
  18. What is the difference between odd and even parity?
  19. What type of wiring scheme is a RJ-45 connector used in? What the advantages and disadvantages to other connectors?
  20. What are the limitations of the use of radio as a transmission medium in communications?
  21. Describe what CMSA/CD is.
  22. Describe wave length division multiplexing (or FDM). Describe spread spectrum multiplexing.
  23. How is a modulated carrier used?
  24. Briefly describe time division multiplexing.
  25. Name some mechanisms used to avoid network congestion.
  26. What is the difference between synchronous and asynchronous communication.
  27. What is the purpose of a transciever?
  28. What is the purpose of a router? Why are they required?
  29. How and why is byte stuffing used?
  30. Briefly describe frequency division multiplexing.
  31. Describe the concept of a checksum.
  32. What purpose do packets serve in communications?
  33. Define bandwidth.
  34. Describe the acronym LAN.
  35. What is a phase shift? How is it used?
  36. Describe the advantages and disadvantages of shared communications links.
  37. Compare and contrast frequency and amplitude modulation.
  38. Describe the important elements of a LocalTalk (token-ring, ethernet) network.
  39. Describe connectionless versus connection oriented service.
  40. Describe the concept of locality of reference.
  41. Describe the concept of a cyclic redundancy check.
  42. What is a NIC and what does it do?
  43. Compare ring and bus LAN topologies.
  44. Why are NICs used?
  45. How is a network analyzer used?
  46. What is an AUI?
  47. Why are hardware addresses used for NIC's?
  48. Suppose 100000 7-bit characters are sent across an RS-232 connection operating at 38400 baud. How long would the transmission require?
  49. If a satellite orbits exactly 20,000 miles above the earth's surface, how long does it take a radio signal to reach the satellite and be sent back (assume the signal propagates at the speed of light, and that the satellite takes 53 microseconds to retransmit a signal). Assume the speed of light is 299,792,458 meters per second. Show all work.
  50. You are going to transmit a 20MB file over a 10Mbps network. Assume there is no overhead involved in transmitting the data. How long will it take to transmit the the 20MB file.
  51. What is frame relay and where and how is it used?
  52. Can one network technology be used for both LAN and WAN connections?
  53. Why is frame relay inappropriate for LAN connections?
  54. Would you expect queueing delays, access delays and propagation delays to be longer on a LAN or WAN? Explain for each delay type.
  55. How much data can be present on an Ethernet segment at one time? Calculcate the delay throughput product for an Ethernet speed at _____ Mbps, length of _____ meters and travling at _____ % the speed of light.
  56. What's the difference between MBps and Mbps?
  57. Where and why is a sliding window protocol used?
  58. What is a virtual network?
  59. What size is the address space for IPv4? For IPv6?
  60. What is CIDR addressing? is xxx.xxx.xxx.xxx a valid IP address?
  61. What are A, B and C IP address rnages?
  62. What is ARP? Why do we need it? How many responses does a computer expect to receive from an ARP request?
  63. A computer gets two different responses (hardware addresses) to an ARP request. How does it handle this?
  64. What is MTU? What does it describe?
  65. What is the size of an IPv6 datagram?
  66. What is the Time To Live field used for in an IP datagram?
  67. Describe what ICMP is.
  68. What is UDP? How big can a UDP message be? Where is it used?