1. IT skills: compose URLs, beware of phishing IT concepts: parts of a URL, secure http, shortened URL, phishing, malware, domain name, directory, file name, extension, path, communication protocol This work is licensed under a Creative Commons Attribution-Noncommercial- Share Alike 3.0 License. URLs – uniform resource locators

2. Internet concepts – Applications – Implications – Technology Internet skills – Application development – Content creation – User skills Where does this topic fit?

3. Client Server request page http://som.csudh.edu/fac/lpress/shortbio.htm URL, uniform resource locator Click on the link and see what happens.

4. http://som.csudh.edu/fac/lpress/shortbio.htm Four parts of the URL

5. http://som.csudh.edu/fac/lpress/shortbio.htm http://

6. http://som.csudh.edu/fac/lpress/shortbio.htm The domain name

7. root staff fac jsmith jdoe admin... lpress The directory * * http://som.csudh.edu/fac/lpress/shortbio.htm

8. root staff fac jsmith jdoe admin... lpress shortbio.htm http://som.csudh.edu/fac/lpress/shortbio.htm The file name

9. http://bit.ly/djeREW URLs may be shortened http://www.csudh.edu/studentaffairs/financialaid/faq.sh tml#apply_for_scholarships Click both links and see what happens. Try shortening a link of your own using the service at http://bit.ly.http://bit.ly

10. Know the source of a shortened URL http://bit.ly/9dLHk5 Click the link and see what happens.

11. Know the source of a link Free money and fame Click the link and see what happens.

12. som.csudh.edu/fac/lpress/shortbio.htm You can delete the http:// Click the link and see what happens.

13. http://som.csudh.edu/fac/lpress/ You can delete the file name Click the link and see what happens.

14. Summary This request is for a Web (http) server The server program is running on a computer with the domain name som.csudh.edu Look in a subdirectory called fac/lpress If there is a file called shortbio.htm, send it back to the client to be displayed; if not, send an error message back to the client http://som.csudh.edu/fac/lpress/shortbio.htm Domain name = the unique name of a computer on the Internet

15. 1. Without looking back, can you describe the four parts of a URL and explain what each means? 2. If you accidentally misspell the domain name in our class URL: http://som.csudX.edu/fac/lpress/275/index.htm you get an error message. Explain why. 3. If you accidentally misspell the file name in our class URL: http://som.csudh.edu/fac/lpress/275/indeZ.htm you get a different error message. Explain why it is different. 4. These two URLs: http://som.csudh.edu/fac/lpress/275/index.htm http://som.csudh.edu/fac/lpress/275/ Retrieve the same Web page. Explain why. 5. The https protocol has been around for years. Why didn’t everyone use it instead of http from the start? Self-study questions