1. IT skills: IT concepts: Web client (browser), Web server, network connection, URL, mobile client, peer-to- peer application This work is licensed under a Creative Commons Attribution-Noncommercial- Share Alike 3.0 License. Retrieving a Web page

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

3. Client and server Client Server

4. What happens next? Uniform resource locator (URL)

5. Establish a temporary connection Client Server

6. Request the page Client Server Request

7. Send the page to the client Client Server Request page

8. Client displays the page Client Server Request

9. page Drop the connection Client Server Request

10. Data flow Web server program Memory Storage Requested page Web client program Memory Display Requested page Client Server Request Page The Internet

11. What if the requested page is not found?

12. Pages with links Client Server 1 Server 2 1. Get first page 2. Get second page

13. Mobile Web clients

14. Operating system Client program Memory in peer-to-peer applications Server program

15. 1. Establish a temporary connection between the client and server 2. Client sends the request to the server 3. Server returns the requested page or an error message 4. Client displays whatever the server returns 5. Disconnect Client Server request page Summary: retrieving a Web page

16. Questions

17. 1. 2. 3. 4. 5. Client Server request page Without looking back, do you recall the steps in retrieving a Web page?

18. 1.Does a URL show both the computer to connect to and the name of the file to retrieve or just the file name? Explain your answer. 2.What happens if the user accidentally misspells the URL? 3.Can one server be handling requests from more than one client at a time? Explain your answer. 4.Do the terms client and server refer to hardware or software? Explain your answer.