Chris Johnson, Index
Open Assessment From 1997-8
The aim of this assessed exercise is to give you practice at using the world's computer resources to
research and present a given problem. A paper copy of the solution should be handed to your tutor in the
week 5 tutorial. You should use the HCI lab in week 2 to surf the Internet and gather information for the
You should write an essay of no more than 2,000 words to answer the question given below. Marks will
be allocated for the style and presentation of your argument. Marks will also be allocated for the
references that you use. You should cite the Uniform Resource Locators (URLs) of the pages that you
visit. Here is an example of one of these references . You should also cite any books that you find
useful. Here is an example of a book reference . Here is an example of a journal reference .
Although it is twenty years old and quite challenging for an initial course, this article is regarded as a
mile-stone in computer security.
Security weaknesses represent the greatest barrier to commerce over the Internet. Discuss.
A wider ranging review and tutorial on Internet security is available from . An overview of
cryptography is provided at . There is also a mass of useful information about the Visa credit card
company's plans for electronic commerce , look under the New Technologies section.
Please do not simply focus upon the technology. You are strongly urged to consider the social and
economic barriers that prevent the widespread adoption of electronic commerce.
Health warning: some of the new cryptographic material is extremely complex. Do not worry if you
cannot follow all of the details. These will be discussed in more detail by subsequent courses. The
important point for this essay is that you understand the impact that these techniques might have upon
This exercise is worth 20 marks out of the 100 that are associated with the HCI course. The following
marking scheme will be applied:
- introduction and conclusion (5 marks).
The essay must begin by identifying the main issues. It should motivate the reader that the topic
is important and it should identify the structure of the argument that will be presented. The
conclusion of the essay should summarise the main points in this argument and should clearly
identify the main finding from the research.
- argument (10 marks).
The essay must clearly argue the case for or against the question. The argument MUST be
supported by evidence in the form of relevant citations and quotations.
- presentation (5 marks).
The essay should be produced using a word processor such as ClarisWorks. It may contain diagrams and
illustrations if appropriate.
This assessed exercice does count towards your final degree mark and must be handed in to your
tutor during your tutorial in week 5.
 A. Tanenbaum, Operating Systems, Prentice Hall, London, 1989.
 R.M. Needham and M.D. Schroeder, Using Encryption for Authentication in Large Networks of
Computers, Communications of the ACM. Volume 21, Number 12, 993-999, December, 1978.