It is an intermediate component between two end points participating in data transferring process on the network. For example, the process is taken in server-computer relation. So, it is special software or a computer dedicated to the process. It may exist as an individual computer or a firewall devoted to filtering some irrelevant traffic.
Advantages: the cache of a server can be used by all users. If several sites have been just asked for or visited they are to be registered in cache of such a server, which is known to present a faster answer for the request. Proxy auctioning can be logged, which is considered to be useful for shooting troubles.
How does it work?
Let’s consider one simple example to understand how it works:
Having received a demand from a web page by a server, a local cache of previous pages is looked through. If the asked for page is found in the cache, it will be sent to a customer without connection to the web. If the demanded page is not found in cache, a client will be used by a server to be presented on a customer behalf. Thus, using one of its addresses, the server makes request for the page instead of you. Having returned the page, the original request is related by the request and a customer achieves the page.
Unfortunately, both legal and illegal actions can be committed by using the server. Security facilitating is the main purpose of its usage, cache services are not the main ones. A customer privacy enabling the server is used for and searching some data in the web while staying unidentified too. On the other hand, it can be used for traffic monitoring, therefore endangering customer’s traffic and activities.
In this case the server is invisible for a customer, because all the demands seem to be directly received from the resources and web pages you have appealed to. However, the address of such a server is specified by a browser or other programs as a configuration possibility.
Your browser can be configured to use a proxy constantly or it can be accessed online. It may be used by many customers or only one for a server. There are different types of them, where DNS is one of the variants.