Electronic Commerce, 7th Edition
Solutions 8-1
Electronic Commerce, 7th Edition
14188-37032
Chapter 8 Solutions
Review Questions
1. Compare the two- and three-tier Web client/server architectures and
indicate the role of each tier in each architecture. Which architecture is the
most likely candidate for an electronic commerce site? Explain why in about
100 words.
Answer: Responses may vary, but if there is a database or additional processing or
structure needed, then a 3-tier is the best choice. If a basic e-commerce site is wanted,
a 2-tier is called for. Most students should choose the 3-tier, however, as it provides
the most flexibility with e-commerce.
2. Describe and briefly discuss two important measures of a Web site’s
performance.
Answer: Two possible answers are the connection speed (T1 line vs. T3 line) and the
number of users that the system can satisfy at any one time.
3. Beginning with the links provided in the Online Companion, locate more
information about two of the three Web servers discussed in the chapter:
Apache, Microsoft IIS, and Sun JSWS. Write approximately 250 words
about each of the two servers you choose. Include descriptions of six features
for each Web server and indicate the computer platforms and operating
systems on which each runs.
Answer: Responses may vary, but should include the operating systems that will work
on each server, who is using the server, what will work on each server and what will
not, and how easily scalable and configurable each server is.
4. In one paragraph, outline the main differences between a desktop PC and a
computer that would be suitable as a Web server for a small Web site.
Answer: Responses will vary, but should include sizes of the hard drive, memory, and
processor speed.
5. Using the Web or your school library, find articles that discuss the types of
server hardware used by at least one electronic commerce site. Outline that
site’s architecture and approach to server hardware and software in an essay
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of about 300 words.
Answer: Responses will vary, but students can consider Amazon.com’s Web site,
which uses the BEA WebLogic Server.
Exercises
1. You are the information systems director for Abbon Laboratories, a
biotechnology research firm with about 100 employees. Alice Stampler,
Abbon’s president, is aware that Abbon’s incoming e-mail includes a great
deal of spam and has always complained about the time it takes her to delete
it. More importantly, she is concerned about the time wasted by the
company’s employees. Just thinking about those expensive Ph.D. researchers
spending time deleting half of their e-mail drives her to distraction. Alice just
read a story in a business magazine about naïve Bayesian spam filters. Being
a Ph.D. herself, she is fascinated by the prospect that sophisticated
mathematics might solve the company’s spam problem. Alice asks you to find
out all you can about naïve Bayesian filters and present a short report (about
200 words) in which you evaluate the technique and whether it can work for
Abbon. Alice envisions one filter installed on the e-mail server that would
screen all e-mail as it enters the company’s network.You can use your
library, your favorite search engines, or the links in the Online Companion
under the heading Naïve Bayesian Filters to do your research.
Answer: In software that contains a naive Bayesian filter the software begins by not
classifying messages. The user reviews messages and indicates to the software which
messages are spam and which are not. The software gradually learns (by revising its
estimates of the probability that a message element appears in a spam message) to
identify spam messages. After seeing a few dozen messages classified, the naive
Bayesian filter can successfully classify spam messages about 80 percent of the time.
As the filter continues to work, the user reviews its classifications and tells the
software when it makes a mistake. After classifying a few hundred messages (and
being corrected by the user when it errs), a naive Bayesian filter typically reaches
correct spam classification rates above 95 percent. Although these filters are highly
effective and have low false positive rates, they must be trained, which takes time.
The training is best done by each individual user because one person’s spam can be
another person’s important message. Having users train their own filters provides the
most rapid training and the best results.
2. You created a Web site for International Paper Products and Pulp, complete
with links to other pages on your site and to pages on the Internet. Bob
Pardee, your supervisor, wants you to check periodically that the links on the
corporate site are still valid. Instead of purchasing and installing a linkchecking program, you decide to investigate online link checkers (Web sites
that allow you to enter a Web site’s root or home address and then check all
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Solutions 8-3
the links that emanate from that site). Use Link Check or Elsop LinkScan
Quick Check to check the links on any site of your choice. Print a few pages
of the report and be prepared to turn them in to your instructor. Be patient.
The program takes a little time to complete its work - especially on a Web
page that has a large number of links.
Answer: Responses may vary, but have the students check their favorite Web site and
submit the paperwork.
3. In researching Web server computers, you find that many companies that
sell these computers offer a configuration option for controlling computers’
disk drives called “RAID.” Using the Web and your library, investigate the
purpose of RAID controllers. Learn what these controllers do and how they
do it. Summarize your findings in a 600-word briefing report suitable for
presentation to a nontechnical manager.
Answer: Responses will vary, but should include the definition: a redundant array of
inexpensive disks, as well as some of the uses for RAID. Some items that students
should focus on include: a demand for an efficient and cost-effective method to
protect customer data, quick integration, a robust feature set, ease of use, and
increased stability (through the use of RAID software architecture).
Cases
Case 1: Microsoft and the People’s Republic of China
1. Answers will vary, but possible arguments for requiring all government agencies to
use only open source software on their Web servers include: no licensing fees, access
to source code can allow customization to meet local needs, full access to source code
may offer security reassurances, proprietary software may contain unknown
dangerous code, ability to choose from a range of competitors for software
modification and support, and free upgrades as the software develops.
2. Answers will vary, but possible briefing points that would help promote the Windows
operating system software on Web servers include: guaranteed software support and
less effort to install, maintain, and update Microsoft products.
3. Answers will vary, but should include consideration of the qualities unique to
Windows and Linux that would make one more appropriate to a certain organization.
These qualities are outlined in the chapter beginning on page 366.
4. Answers will vary, but possible strategies these companies could use to expand their
market share in the PRC include: offer services to tailor Linux systems to meet the
unique needs of different organizations, emphasize ways they can save customers
money providing the same services and delivering the same value as Microsoft for
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Solutions 8-4
less money, and develop expertise in servicing the unique Chinese version of Linux,
Red Flag.
Case 2: Random Walk Shoes
1. Answers will vary based on individual interpretation of the services the Web site will
need to provide and the Web traffic it will need to handle. The minimum amount of
disk storage required would be 430 MB for the data and software mentioned in the
case plus space for the server operating system, plus some unused space to allow
efficient operation and room for future expansion. For busy Web servers, the
maximum RAM and processor speed available for the selected equipment is usually
recommended to optimize site response (multiple processors may not be required
given Amy's initial limited traffic expectations). Answers will also vary based on the
constantly increasing capacities of Web server computer equipment.
2. Answers will vary based on personal opinion, but should include discussion of
advantages and disadvantages associated with specific features of the selected
operating system. These features are presented in the chapter beginning on page 366.
If no one operating system is selected, the answer should provide specific evidence
why no one operating system would provide an advantage in the scenario described.
3. Answers will vary based on personal opinion, but should include discussion of
advantages and disadvantages associated with specific features of the selected Web
server software package. Features of these packages are presented in the chapter
starting on page 366.