An intermediary server, otherwise called an "intermediary" or "application level portal", is a PC that goes about as a passage between a nearby system (e.g., all the PCs at one organization or in one building) and a bigger scale system, for example, the Internet.
Intermediary servers give expanded execution and security.
Sometimes, they screen workers' utilization of outside assets.
An intermediary server lives up to expectations by blocking associations in the middle of sender and recipient.
All approaching information enters through one port and is sent to whatever is left of the system by means of another port. By blocking direct access between two systems, intermediary servers make it substantially more troublesome for programmers to get inside locations and points of interest of a private system.
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.
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.
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.
Proxies can be of various types and each of its type serves a specific purpose. The most common types are as follows: