1. Structure of the Internet

2. Internet Structure LAN ISP Internet Backbone

3. Addresses Your PC Web Site www.visitme.com 192.168.2.215 26.14.37.198 Domain Name System Domain Name Server

4. Message Flow

5. Internet Foundation Your PC Web Site Transmission Control Protocol/ Internet Protocol (TCP/IP)

6. Client/Server Applications

7. Client/Server Application Server Client Application Protocol Request Response

8. Division of Labor in a Client/Server System Server Client Interface Processing Data Management Display Form Validate DataCompute Total Compute Tax Check Inventory Update Inventory

9. Multi-tiered Client/Server Application Application Server Client Data Management Database Server Interface Processing Data Management

10. Internet Applications

11. Internet Applications (i.e., Web Application) Server Client Application Protocol Web Server Web Browser HTTP (Hypertext Transfer Protocol)

12. Common Internet Application Protocols Server Client Application Protocol HTTP – Web SMTP – E-mail FTP – File Transfer IRC – Chat Companies can, and do, create their own application protocols.

13. 192.168.2.215 26.14.37.198 Ports Server Client Web Server Web Browser HTTPSMTP E-mail Server E-mail Client 251837 802134

14. Web Technologies

15. Web Browsers and Servers Web Servers Web Browsers Internet Explorer Netscape Mozilla Opera Microsoft IIS Netscape Internet Server Apache

16. Web Development Options Web Server Web Browser HTML Scripts Executables Scripts SQL

17. Web Programming Tools Web Server Web Browser Java/JavaScript/JScript Visual Basic/VBScript PERL ASP/JSP C/C++/COBOL/…