Surely, every owner of a computer connected to the Internet at least once, but heard the phrase "proxy server" or "proxy". Some users could decide for themselves that there are already many obscure terms on the Web to delve into what a proxy server is. In fact, there is a kind of test that indicates the need for a thorough study of proxies: if there are no problems with working on the Global Network, then the question "what is a proxy server and why is it needed?" It is interesting, first of all, from the theoretical side. However, the capabilities provided by such a server may interest even a simple user who is just viewing articles on the pages of sites.
To understand what a proxy server is, you need to familiarize yourself with the principle of operation of network applications. Viewing resources on the global network is carried out using a special program - a browser. Opera, Google Chrome, Firefox, Internet Explorer and others - this is not a complete list of popular browsers. Consider a simplified mechanism for their work. The function assigned to such programs is extremely simple and consists in sending a user or service request to web pages located on distant servers. The response is sent to the request and displayed. Of course, everything is much more complicated, but to understand the mechanism of this scheme is enough.
Obviously, if you manage to process the request in a certain way, then the result can be flexibly controlled. Without understanding what a proxy server is, such an adjustment cannot be made. “Proxy”, installed on a computer, is a special software package that serves as an intermediary between the browser (or any other client sending requests to the Network) and the requested resource. The browser sends the request not to the target site, but to the proxy server, which makes the necessary corrections and transfers it to the network.
Here are a few examples where the proxy is hard to overestimate:
- Internet traffic is paid per megabyte. Since each request and response flow of information (text, image) passes through a “proxy”, its caching system saves a part of the data. In subsequent requests for the same resource, part of the information is not re-downloaded from the Web, but substituted from the cache. Thanks to this, the volume of traffic is significantly saved, and the speed of subsequent page loads increases. For users of GPRS connections, such a system is indispensable;
- To reduce the amount of data (not caching). Some of the information is compressed. This is how Opera Turbo works in a well-known browser;
- to block access to resources. If blocked resources are specified in the proxy server settings, then clients accessing the Network through such a server can receive a response only from resources not included in the blacklist. In large companies, this is precisely the way that employees are denied access to services (social networks, ICQ);
- for anonymous surfing and removal of access restrictions on some sites. In this case, the target resource does not see the information of the client, but the proxy, which is configured as necessary;
- to block ads. By compiling a blacklist of banners and unwanted links, you can remove ads in much the same way as the famous Ad Mucher.
Installation of the proxy server begins with the selection of the desired one (HandyCache, CoolProxy, TOR, etc.). As mentioned above, their capabilities differ and are determined by the class of tasks being solved. A user who knows what a proxy server is, starts the configuration by indicating the client programs IP address and port. If the proxy is installed on the user's computer, then usually the address is localhost, and for those located on the Network, it is specified in the description for it. Next, settings are made to the server itself (depending on the destination).