CSE 190: Internet E-Commerce

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CSE 190 Internet E-Commerce

• Lecture 5

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Exam Material

• Lectures 1-4 (Presentation Tier)
• 3-tier architecture
• HTML
• Style sheets
• Javascript
• DOM
• HTTP
• Web servers

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Exam 3-Tier Architecture

• What are the three tiers?
• Presentation purpose of
• Firewall
• Cache
• Load balancing server
• Web server
• How to recover from failure?
• Application Tier
• How to recover from failure?
• Data Tier
• Why cant this be combined with application tier?

4
Exam HTML

• Purpose difference with other doc formats
• Structure of an HTML document
• General tag syntax
• Familiar with tags html, head, body, H, A, UL,
  OL, form, input, table, tr, td, br, img, center,
  frame, script
• Components of URL
• URL encoding ( url?arg1abcdarg2ef20 )
• Difference between relative and absolute URL

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Exam Stylesheets

• Purpose
• What is meant by cascading?
• General CSS syntax
• Applying style to
• All tags of type X
• All elements of class X
• Specify an external stylesheet, internal
  stylesheet, and inline style

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Exam Javascript

• Purpose
• How to include in a page
• Writing text to HTML page
• Declaring variables
• Declaring functions
• Returning a value
• Displaying an alert
• When the script executes

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Exam HTTP

• Status codes, classes of
• Purpose of GET, POST, HEAD
• Syntax of GET, POST
• Request fields Host, Content-Length
• Response fields Content-Type

8
Exam Web Servers

• Purpose of
• Apache multi-client model
• Apache configuration Purpose of
• Port
• DocumentRoot
• ServerName
• User
• HTTP authentication
• SSL
• Virtual Hosts
• CGI

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Example Exam Questions

• (2 pts) Draw explain the relationship between a
  load balancer and a cluster of web servers.
• (3 pts) Show the URL that represents a GET
  request for domain ucsd.edu and document
  /student/ski/home.asp with two arguments, task
  with value open and the second shibboleth with
  ali baba (no quotes).
• (3 pts) Explain two advantages of stylesheets
  over plain HTML. Write an HTML file that applies
  an internal style to all DIV tags such that the
  attribute font-size is 18.

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Example Exam (cotd)

• (3 pts) Write an HTML page that contains a form
  taking username and password and submits it to
  ucsd.edu/form.cgi using HTTPS. Onlookers may not
  view the password.
• (3 pts) Write HTML code that uses Javascript to
  write Hello World! to the browser window.
• (2 pts) Write a Javascript function that takes
  two numbers and returns their sum.
• (2 pts) Using Javascript to access the DOM,
  access the second form on the page and assign it
  to a variable.

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Example Exam (cotd)

• (3 pts) Show an HTTP/1.0 client send a request
  for a document hello.gif from an HTTP 1.1 server.
  Show both request and response headers. Indicate
  when the connection closes.
• (2 pts) What is the purpose of DocumentRoot in
  Apaches configuration file (httpd.conf)?
• (2 pts) What happens to your web server if a
  hostile user crashes a child process? How does
  the parent recover? Are pages still served?