What is a proxy server

A proxy server is a computer that sits between the client computer and the Internet and provides indirect network services to the client. It can reside on the user's local computer or at various points between the user's computer and the target server on the Internet. The most important role of a proxy server is to provide security.

#The proxy server intercepts all client requests and serves the response from its cache or forwards the request to the real server. The client computer connects to the proxy server, which acknowledges the client request by serving the requested resource/data from a designated server or local cache. Client requests include files or any other resources available on the various servers.

Modern proxy servers do more than forward web requests in the name of data security and network performance. Proxy servers act as firewalls and web filters, providing shared network connections and caching data to speed up common requests. A good proxy server protects users and the internal network from unwanted content that exists on the wild Internet. Finally, proxy servers can provide a high level of privacy.

The proxy server can exist on the same machine as the firewall server, or it can be on a separate server that forwards requests through the firewall.

Types of proxy servers

Proxy servers are classified according to their purpose and function for several types. Some of the most common types and their uses can be described as follows:

Web Proxy

The most common type of proxy application, which works by accessing resources in cached web pages and remotely Files available on the web server to respond to user requests. This facilitates fast and reliable access to data for local network clients. If the requested resource is not found in the cache, the web proxy fetches the file from the remote server and saves a copy in the cache before returning the copy to the client.

Transparent Proxy

Transparent proxies are mainly used to cache websites and overcome simple IP bans. However, these proxies do not provide any user anonymity since the user’s original IP address is exposed. The transparent proxy is not specifically configured on the client computer.

Anonymous Proxies

Anonymous proxies do not hide a user’s original IP address; however, they provide sufficient anonymity for most users. Anonymous proxies are easy to detect.

Twisted Proxy

Twisted Proxy is a proxy that identifies itself as a proxy server and modifies the HTTP header, masking the original IP address.

Forward proxy

A forward proxy is a sequence of data retrieved from sources on the Internet that respond to client requests. It is also known as an Internet-facing proxy.

Open Proxies

Open proxies belong to the category of forward proxy servers, which are accessible to any Internet user because they can receive and return requests from any client computer. Meanwhile, anonymous open proxies are used to hide IP addresses from anonymous users.

Reverse Proxy

A reverse proxy (also called a proxy) typically receives requests from the Internet and forward it to the internal web server. A reverse proxy server forwards requests to one or more proxy servers, whose responses are returned to the client computer without the user of the client computer knowing the origin of the response.

How does the proxy server work?

Every computer on the Internet needs to have a unique Internet Protocol (IP) address. Think of this IP address as your computer's street address. Just like the post office knows how to send our mail to our street address, the Internet knows how to send the right data to the right computer via IP address.

A proxy server is basically a computer on the Internet with an IP address that our own computer knows. When sending a web request, our request first goes to the proxy server. The proxy server then makes web requests on our behalf, collects responses from the web server, and forwards the web page data so that we can view the page in our browser.

When a proxy server forwards a web request, it can change the data we send and still get the information we want to see. Proxy servers can change our IP address so the web server doesn't know exactly where we are in the world. It encrypts our data so our data cannot be read during transmission. Finally, the proxy server can be based on the IP address

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