CS 558 - Computer Networks
Homework 1

Due: See class webpage.

Question

The following links contains all the necessary information that you need to answer the questions below:


Questions
  1. Show the wave form of the transmission signals when 11110000 is transmitted in the 802.3 Ethernet protocol

  2. Show the wave form of the transmission signals when 11110000 is transmitted using the NRZ encoding

  3. Show the wave form of the transmission signals when 11110000 is transmitted using the RZ encoding

  4. Show the wave form of the transmission signals when 11110000 is transmitted using the 4B/5B encoding (4B/5B uses NRZ to encode 0 and 1 bits).

  5. What percentage of overhead (additional bits) is added to the transmission when 4B/5B encoding is used ?

  6. What is the main advantage in using 4B/5B encoding over NRZ ?

    From answers to questions 5 and 6, you should understand that the 4B/5B encoding method is making a trading off. (Trade-off: what cost is increased to improve some other thing)

  7. What is the name of the encodng scheme used in Gigabit Ethernet ?

  8. What percentage of overhead (additional bits) is added to the transmission when data is transmitted on Gigabit Ethernet ?

  9. What is the name of the encoding scheme used in FDDI ?

  10. What is the name of the encoding scheme used in Ethernet ?