A proxy is a program or computer system that acts as an intermediary for clients who are seeking resources from the web. The client will connect to the proxy, usually requesting a service like a connection, file, web page, or some other resource from another server. The proxy service will then evaluate that request according to its programming rules. If the request has been validated by the filter, the proxy service will then execute the request. Often proxies are used to filter internet traffic or make it anonymous by providing a different protocol or IP address.
Anonymous Proxy There are hundreds of proxy servers available online and they can be used for a large variety of purposes. Many of them are used to keep computers anonymous for security reasons because a proxy server will generate a different IP address so the request cannot be traced to the client’s computer. The main job for anonymous proxy usage online is to make the client’s web surfing anonymous. The most common proxy for this is an open proxy because they are hard to track and well suited for individuals who do not want to be traced by computer criminals or political dissidents. This can also provide increased security by hiding a client’s identity from malicious websites.
Web Proxies A proxy server that mainly focuses on World Wide Web traffic is known as a web proxy. The most popular use of a web proxy is to act as a web caching service. The majority of proxy programs provide an option to deny access to URLs that are on the ‘blacklist’, this is known as content filtering. This filtering system is often used in educational environments, corporate environments, and anyplace else that require content filtering. Some proxies can also reformate web pages for specific audiences or devices, such as PDAs or cell phones.
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