THE WORLD WIDE WEB

The world wide web (WWW) is a computer network which consists which of a collection of Internet sites. These Internet sites offer various resources such as text, graphics, audio, video, and animation. Following are the various component off the web.

• Web client is a system which request for web service on the internet for performing its own tasks.
• Web server is a group of system that provide web service for request made by a web client.
• web browser is an application which allows a web client to avail the web services. The web browser converts HTML files into web pages and provides them to the web client. The commonly used web browsers are Microsoft Internet Explorer (MSIE) and Netscape communicator (NC).

Communication between web client and server on the web

The web uses various protocol such as Hypertext Transfer Protocol  (HTTP) and TCP/IP to enable communication between a web client a web server.

TCP/IP protocol consists of a set of rule for exchanging information between application across the Internet. the TCP/IP protocol is a connection-oriented reliable service that transmits information in the form of packets. The TCP/IP protocol sends the packets to their intended destinations and the recipient  sends an acknowledgement to the sander on receiving the packets. The protocol re-transmits the data, in case acknowledgement is not received. An internet protocol is a set of standard rule that provides a standard for the information that is to be exchanged over the Internet.

HTTP is a TCP/IP application-layer protocol that enables you to establish connectivity between the client and the server for developing web-based application. The HTTP protocol is  based on the client/server model. When a web page is selected, the web browser establishes a connection with the TCP/IP port on the client’s system and transmits an HTTP header containing the request for the selected web page’s from web server. The web server provides the requested data to the web browser along with an HTTP header.

The steps to communication between a web client and web server are:

1. A web client request for a web service to the web browser.
2. The web browser receives, interprets and then transfer the request to the web server.
3. The web server receives the request from the web browser and sends the service to the client, running the web browser, in the from of an HTML file.
4. The web browser receives the HTML file, converts the HTML file into a web page and than sends it to web client
5. The web client receives the web service in the form of a web page.