1. Web Applications BIS4430 – unit 8

2. Learning Objectives Explain the uses of web application frameworks Relate the client-side, server-side architecture to dynamically generated websites Explain the increased usability requirements for dynamically generated websites Compare and contrast current web applications e.g. search engines, webmail, discussion boards

3. Client-server reminder

4. Web Application Frameworks Tools for developing web applications None are comprehensive System generates controlling code Examples –AJAX –.NET framework

5. AJAX Asynchronous JavaScript and XML Increases interactivity & speed HTML & CSS for formatting JavaScript for dynamically displayed information XML for asynchronous data exchange with the server

6. .NET framework VB.NETC# Compiler Common Language Runtime Common Intermediate Language other languages……….

7. Dynamically generated websites Definitions Pages generated by server-side scripts Pages that alter based on user activity Moving images or flash movies

8. When to go Dynamic? how will server-side scripting affect the performance of your site? will it affect the caching of web pages on the client side? how will it affect the user’s ability to bookmark pages? how will the url be affected? - very important wrt search engines will bookmarked urls return the user to the same information at a later date?

9. Advantages develop fewer pages automate content updates future-proof the site

10. Disadvantages Strain on low specification web servers Increased security issues URL change affecting search engines Links from external sites will need updating

11. DHTML Client-side Reduces load on the server Quicker responses Data storage allows multiple interactions without cookies Caching allows interactivity when offline

12. Improving your search engine results High number of links to your page Keyword placement –at the beginning of a page –repeated many times in the page –used as headings or subheadings –Alternative text for images –A summary in the noframes tag (only useful for pages in frames - see Unit 9) Paid placement http://www.wdvl.com/Location/Promotion/Search/index.html

13. Forums Essentially a user-created website Part of a website set aside for user interaction –Example – Oasis discussion board Forerunner of weblogs

14. Things to DO: Oasis+ –Unit 8 – Web Applications