group17_the spark:http proxy server.

PROXY SERVER
A proxy server is a server that acts as an intermediary between a workstation user and the Internet so that the enterprise can ensure security, administrative control, and caching service.
Proxy servers have two main purposes:
Improve Performance: Proxy servers can improve performance for groups of users. This is because it saves the results of all requests for a certain amount of time. Consider the case where both user X and user Y access the World Wide Web through a proxy server. First user X requests a certain Web page, which we'll call Page 1. Sometime later, user Y requests the same page. Instead of forwarding the request to the Web server where Page 1 resides, which can be a time-consuming operation, the proxy server simply returns the Page 1 that it already fetched for user X,hence this is a much faster operation. Real proxy servers support hundreds or thousands of users. The major online services such as America Online, MSN and Yahoo, for example, employ an array of proxy servers.
Filter Requests: Proxy servers can also be used to filter requests. For example, a company might use a proxy server to prevent its employees from accessing a specific set of Web sites.it may also commmunicate to daemon based or ICAP based anti virus software to provide security against virus and other malware by scanning incoming content in real time before it enters the network.
The HYPERTEXT TRANSFER PROTOCOL is used mainly to access data on the world wide web . the protocol tranfers datd in the form of plain text, hypertext , audio, video and so on. It is called the hypertext transfer protocol because it is used in an envirornment where there are rapid jumps from one document to another.During the HTTP connection,the IP address of the client machine is necessarily transmitted in order to get the information back. This allows a server to identify the source of the web request.
HTTP proxy servers interprets web access.
HTTP is a proxy server which acts as an middleman between your web browser and an end server.Instead of directly connecting to web page it connects to the proxy which forwards the request to end server. They support many programms browsers, download managers. They can be united into a chain and in a chain can be mixed with other types of proxy servers like SOCKS and CGI.