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 essay.

Task description

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 [1]. You should also cite any books that you find useful. Here is an example of a book reference [2]. Here is an example of a journal reference [3]. Although it is twenty years old and quite challenging for an initial course, this article is regarded as a mile-stone in computer security.

The Question

Security weaknesses represent the greatest barrier to commerce over the Internet. Discuss.


A wider ranging review and tutorial on Internet security is available from [4]. An overview of cryptography is provided at [5]. There is also a mass of useful information about the Visa credit card company's plans for electronic commerce [6], 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 today's consumers.

Marking Scheme

This exercise is worth 20 marks out of the 100 that are associated with the HCI course. The following marking scheme will be applied:


This assessed exercice does count towards your final degree mark and must be handed in to your tutor during your tutorial in week 5.



[2] A. Tanenbaum, Operating Systems, Prentice Hall, London, 1989.

[3] 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.