We explain what a proxy server is, how it works and the different types available

An integral tool used by many to maintain anonymity when browsing the web, a proxy server is a server that sits between a user’s device, and the server that it’s accessing information from.

The main purpose of a proxy server is to hide the identity of the device, while the destination server could be anything ranging from a website, to a direct connection with another device.

These tools have developed a bad reputation in light of the fact they are routinely used by malicious actors, such as hackers, or criminals, to hide their identity when conducting illicit online activities – but they have a range of positive benefits. Proxy servers can be very useful for testing a connection, for instance.

A user’s IP address, their defacto online identifier, is sent to the location of the information being accessed, for example, a Google search will send your IP address to Google. But a proxy server can be used to mask the true identity of the user – protecting both the requester and the information source from each other – by stopping this information from being shared.

How does a proxy server work?

These tools behave as intermediaries. Proxy servers switch the IP address when a request is sent through one, before passing this on to the source of information.

What are proxy servers used for?

Proxy servers can be used for a variety of different reasons, including the request web pages, bypassing services controls that block certain IP addresses or protecting the user’s identity if they’re trying to access a website with sensitive information on it.

Although using a proxy may seem a little suspicious, there are many occasions when a user may want to use one. For example, if they want to access content or a website blocked by an IP (such as from within a school or business network), to bypass censorship or if they want to hide their identity from the website or service they’re trying to connect to.

At an organisational level, rather than an individual one, proxy servers can also be used for content filtering, to prevent users from accessing certain sites or to prevent certain data from leaving the corporate network, to improve security by hiding the IP addresses of people using an internal network and by speeding up websites and web-based servers by load-balancing and caching information.

Types of proxy server

There are lots of different types of proxy servers, with each having a different function.

For example, a gateway or tunneling proxy is used to pass on unmodified requests to the information source. A forward proxy is used to extract information from a source (usually internet-based), while a reverse proxy controls access to a server on a private network. This third type can also be used to hide the IP address of the source server. The request is forwarded on from the proxy to the ordinary server, and then the response is forwarded on as if it’s coming from the ordinary server, meaning the user won’t know the origin.

Reverse proxies are commonly used in business to encrypt websites using SSL, removing the need for businesses to implement separate SSL Server Certificates for multiple hosts. They can also be used for load balancing, by acting as the middleman and then distributing loads to various servers upon which application servers sit. Reverse proxy servers are also an essential part of speeding up the operation of a website, using caching to locally load the content from the browser rather from the originating server and compressing content, such as javascript, to make the content load faster and offer a better user experience.

Open proxy servers are a type of forward proxy that allow anyone to access them. There are hundreds of thousands all across the internet, with some (anonymous open proxy servers) allowing users to hide their IP address while they’re browsing. This type will tell the source it’s a proxy server, but it won’t pass on the user’s IP address.

Other IPs that hide a user’s identity include a distorting proxy that gives an incorrect IP address, but tells the source it is a proxy server, a transparent proxy that identifies itself as a proxy and passes your address along anyway and a high anonymity proxy that gives a fake IP address and doesn’t tell the source server it’s hiding the identity of the requester.

Source : itpro