In the previous articles we have learnt about Web Server, Client and Network technologies. Where Clients request for information to the Web Server via network. Therefore, first of all Files holding the information must be created. Files has to be stored in a central location that is Web Server. Clients has to be allowed to access those file whenever required. A connection between Client and Server must be established. So that files can travel across the world via Internet. The Files that Server provided to clients are called Web pages. The individual who develops those web pages is called Web Developer.
Web Developers creates web pages using HTML syntax. HTML stands for Hyper Text Markup Language. HTML web pages must be organized and stored in a Server. The organization of web pages into directories and files stored on the Hard Disk of a Server is called ‘Web Site’ creation. As I mention in the previous articles Server computers used special software called Web Server software has the features like Website management, handing clients request, responding to client with accurate information.
Web clients used browser software to connect to the appropriate Server, query the server for information and provides an interface to return the requested information. Browser communicates with Server with 4 steps HTTP transaction.
Before client and server can exchange information, they must establish a connection first. TCP/IP is used for connection over the Internet. To communicate with Server, client must give IP address of the server along with sub protocol HTTP, FTP etc. Along with this specific port numbers also required. HTTP default port number is 80, and FTP default port number is 21.
If the protocols are configured on default port number than Web Server connection can be established by –
If protocols are other than default, then
Protocol://IP address:port number
And in this case default webpage will be :
Protocol://IP address/webpage name
Protocol://IP address:port number/index.html
If clients request any other web pages then web page name will be changed and if the web page not found by server then it will return a error message.
Server will close the TCP/IP connection with the browser after it responds to the client’s request. Hence both can handle unexpected closing of connection and connection closed on browser’s stop button.