This is an individual assignment. You have to answer all of the questions. The
answers should be concise descriptions of your understanding. Greater marks will
be awarded for answers that are straightforward and concrete than for answers that
are sketchy and cumbersome. Marks will be lost for giving irrelevant information.
If, by chance, you think the assumptions are not sufficient to solve the
problem, then you can add the assumptions that you think are necessary. State
explicitly what assumptions that you have made.
Question 1 (10 marks)
Assume that John wants to buy some CD from an online shop called
MusicPlus. Describe step by step (with figures and words):
(a) How John should encrypt the information and send via the Internet so
that the information will be sent securely to MusicPlus.
(b) How MusicPlus can ensure the information received is not being altered
during the transmission process.
Question 2 (10 marks)
What are the differences between key distribution centre and certification
authority? Briefly describe their mechanisms step by step.
Submission deadline is Wednesday 3pm, February 10, 2010. Penalty for late
submission is 10% of your mark per day your submission is late. All submission
items need to be submitted before this date and time.
The following items need to be submitted:
· A printed version of your assignment to be submitted to me or to the Ms.
Josephine Magada(IC office). Your assignment submission must be accompanied by
a signed coversheet.
· You also need to submit an electronic version of your assignment in PDF
(preferred) through the class forum.