What is a Proxy Server?
Proxy Server is basically a computer acting as a doorway between local and large scale networks. For example, in a company all the activated computers within a building will be termed as local networks and the Internet will be the larger network. A proxy server is also known as “application-level gateway” and/or simply “proxy/proxies.” It may be a computer program or an application and forwards clients requests to different servers after processing and filtering them.
In simple words, a proxy server facilitates the demands of a client by providing it access to the required resources and serves as a medium between two connections. Filtering requests is also one of its primary tasks, which is a very important feature as far as data security is concerned. It ensures enhanced performance of all computers connected on a larger network as well as comprehensive data sharing security.
Why Proxy Server is used?
It is used for accessing web pages being used by other computers. Whenever a computer sends request for a specific web page the proxy server retrieves it and sends that web page to the requesting client via web server. Therefore, proxy server is a kind of broker between requested server and remote server. None of them contacts each other directly but only through the proxy server.
It is also used for caching the accessed web pages so that when two clients request for the same web page, one instead of two requests gets not generated. Since the proxy server remembers the web page accessed previously therefore, it instantly delivers it to the client without sending a new request to the web server. This makes the entire process highly efficient and time-saving.
Content filtering is a feature of proxy server which is highly useful when you have installed a firewall on your computer/network. It helps the firewall in filtering incoming and outgoing content thereby offering a second layer of security between the Internet and the local network. Content filtering thus, provides administrative control over the content that is being transmitted through the proxy server. Organizations where content filtering is mandatory for example schools or other regulated entities benefit greatly from proxy servers.
How a Proxy Server Works?
It performs its job by interrupting connections between the sender and receiver and blocks direct accessibility of data to and from two networks. The entire incoming data is allowed entrance through just one port and another port forwards it to the rest of the network. In this way, a proxy server makes it difficult for hackers to access details of a private network by getting hold of its internal address.
Through proxy servers, computers are allowed indirect network connections to different network services. A client connected to proxy server has to send a request for accessing the connection, files or salient resources available on the other network. In response, the proxy server provides access to the required resources by either connecting to that server or serving via cache.
Kinds of Proxy Servers:
Proxies can be of various types and each of its type serves a specific purpose. The most common types are as follows:
1. Free Proxy: Free proxies are applications available to anyone having an internet connection. If users want their IP address to remain hidden then they need to utilize the free proxies while surfing.
2. Reverse Proxies: Reverse Proxies or surrogates are also popular proxy servers. These are usually installed near web server and all the requests from client computers go to the web proxies. This kind of a proxy server is mainly used for accelerating the encryption. For enabling encryption, it is necessary that the proxy server is equipped with a Secure Sockets Layer (SSL).
3. Performance enhancing proxy servers: As the name suggests, are used for improving the performance of the TCP.