Assignment #5 for Computer Networks (Fall 2003)
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Problem #1 -
  You can find the original paper on Ethernet by Metcalfe and Boggs here...
    http://www.acm.org/classics/apr96/
  Please read this paper and answer the following questions (some of these
  questions will not have the answes in this paper -- you will have to dig
  further):
  a) What was the insipriation (the previous work) for Ethernet?
  b) Finish the sentence "... so we shoose to achieve reliability through
     ______________________" (this is a sentence in the paper - find it).
  c) A packet with an destination address of zero is what kind of packet?
  d) What were the parameters for network span, data rate, and maximum
     number of stations?
  e) What does CRC stand for (i.e., what is it an acronym for)?  Did
     Metcalfe get this right?
  f) What is "Q" and what (in modern terminology) is the "load-estimating
     retransmission control algorithm".
  g) For small packets and large number of stations, Metcalfe's analysis
     predicts an efficiency of about 37%.  How can this efficiency be
     improved?  Hint: read the table.

Problem #2 -
  What is the Ethernet capture effect?  Carefully describe it.  What effect
  does it have on the utilization (throughput) of an Ethernet?  You will
  need to dig a little to find out what is the Ethernet capture effect (this
  is not in your book).

Problem #3 -
  As anologies to multiple access protocols, we have talked about several ways
  to share a salt shaker (condiment access protocols they are?).  We have
  demonstrated at least token passing (salt shaker passing)  and CSMA/CD
  (Condiment Sense Multiple Access / Collision Detection).  Can you come-up
  with at least two other ways to share a salt shaker?  Discuss the merits
  of your two new ways with respect to token passing and CSMA/CD.

Problem #4 -
  Compute the 16-bit IP checksum of this assignment (i.e., of the file that is
  this assignment).  Can you make changes to this file such that the checksum
  remains the same?  Submit a print-out of your changed file (highlight the
  changes with a yellow highlighter).  Hint:  See the Christensen tools page
  for checksumming programs.

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