What’s a Proxy Server?

A proxy server is a computer which provides a computer network service to permit clients to make indirect network connections. A client connects to the proxy server, then requests a connection, file, or alternative resource on a server that is different. The resource is provided by the proxy by serving it or by connecting to the designated server. Sometimes, the proxy may alter the response of the server or the customer’s request for assorted functions.
Web proxies

A typical proxy application is a caching Web proxy. This supplies a nearby cache of Web pages and files on remote Web servers, allowing local network clients to get them.

When it receives a request for a Web resource (specified with a URL), a caching proxy looks for the resulting URL in its local cache. It returns the file immediately if found. Otherwise it returns it, gets it from the distant server and saves a copy in the cache. The cache typically uses an expiry algorithm to get rid of documents in the cache, according to size, their age, and access history. Two straightforward cache algorithms are Least Recently Used (LRU) and Least Frequently Used (LFU). LRU removes the least-recently used documents, and LFU removes the least-often used documents.

Internet proxies also can filter the information of Web pages. Some censorware programs – which try to block offensive Web content – are executed as Web proxies. Internet proxies that are other reformat web pages for a particular purpose or audience; for instance, Skweezer reformats web pages for PDAs and cell phones. Network operators may also deploy proxies to intercept computer viruses and other hostile content.

A unique instance of internet proxies are “CGI proxies.” All these are web sites which enable a user to gain access to a website through them. They usually use CGI or PHP to execute the functionality that is proxying. CGI proxies are often used to access web sites blocked by school or corporate proxies. They’re occasionally also used to obtain a level of anonymity since additionally they conceal an individual ‘s own IP address in the web sites they get through the proxy.

You might see references to four various kinds of proxy servers:

Clear Proxy

This kind of proxy server also makes the first IP address accessible through the http headers and identifies itself as a proxy server. All these are typically used to cache sites for his or her capability and don’t essentially supply people who make use of them with any anonymity. On the other hand, using a clear proxy can get you around IP prohibitions that are straightforward. They may be clear in the terms your IP address is shown, not clear in the terms which you don’t know which you’re utilizing it (your system isn’t particularly configured to put it to use.)
Anonymous Proxy

This kind of proxy server identifies itself but will not make the initial IP address accessible. Such a proxy server is not undetectable, but supplies anonymity that is practical for the majority of users.
Distorting Proxy

This kind of proxy server identifies itself but make an incorrect IP address that is first accessible through the http headers.
High Anonymity Proxy

Such a proxy server will not make accessible and doesn’t identify itself the IP address that is original.