What is a Proxy server in networking? | How does it work?


The word proxy means pretending to be something other than actual. In some scenarios, the true identity must be hidden for security and other reasons. A proxy server in networking is an application for hiding client identity from the server.

You might browse sites daily, but you never know how the network captures your information. A company may grant you access via VPN only so that there will not be any exposure to confidential information. 

What is a Proxy server?

A proxy server is an intermediate machine between the two communicating parties. On one side, it connects to the private network, such as a company’s LAN, and the other side connects to the Internet or a public network.

When you browse a website, the HTTP request from the web browser routes to the hosting server over the public Internet via proxy. The response comes via the same proxy to your web browser. It looks like a simple job, but a proxy server adds many valuable functionalities to a business or end-user in a real-world scenario.

How does a proxy server work?

Until now, maybe you are unaware whether you have used any proxy server. As this is a transparent functionality for you. To understand how it operates, let’s first understand what happens when you type a web address in the browser and hit the enter key. 

A request message goes to the server via the Internet. Each machine has a public IP address (maybe more than one) on the Internet. An IP address is similar to a real-world postal address. When someone needs to send a post to you, the sender mentions your address on the envelope and posts via a post office. May also mention his address so that you will get a return if the courier guy can not deliver.

Similarly, on the Internet, a request has a destination IP address (webserver) and source IP address (client or your machine). The server processes the request and sends the response back to the client. In this scenario, no proxy is involved

When using a proxy server. The proxy server works as a gateway and has its own IP address to make this happen. The browser (or router in the office) knows to forward the request to the proxy. Then the proxy server initiates a new request with your data to the web server. It gets the response and delivers the same to your laptop so that you can see the response content.

It looks the same as no proxy. So what the hell proxy server is doing? The magic is in the way; it can modify the request and deliver similar responses. A proxy can change the source IP address for a request, so the server never knows about you. As a security policy, it can block access to some websites or other resources. You may use encryption before sending a request to secure communication.

What are the advantages of a proxy server?

When using a mediator with excellent qualities and intelligence. It always adds value. Companies providing proxies generally cover all company or Individual use cases. Depending on your need, you can turn a feature on or off. Here we will cover the advantages mainly from a company’s point of view. A company is always at a high risk of a security breach. So a good proxy can add many advantages to the operations.

Privacy –  It is a fundamental advantage. A company may hide the identity of its employees and itself from some web servers. Suppose a marketing company wants to get details from a server. The server can not find who requests the information when using a proxy.

Content filtering –  A proxy server can parse the response from the server, and it may stop content from going to the client. It may be because the content may have sensitive or unauthorized data.

Better Bandwidth Utilization – The proxy may cache the responses. So that if any new request comes, the same content can be delivered to the client without any request to the Internet. This looks simple but requires intelligence, as all responses can not be cached. e.g., any live update of the cricket score can’t.

Restrict uploads –  An employee in a company may try to upload a local file to a personal server. It may be a direct file transfer using FTP or as an attachment in the mail. The proxy can detect such content and stop uploading the file to any public server.

Access to restricted resources –  Restrict resources mean you can not access an external server from your computer. This may be because of server has blocked the IPs you are using. But if you use a proxy, your IP will be hidden, and you will get access to resources.

Is the use of a Proxy always good?

The answer is, in the use case, why do you need a proxy? If yes, then go for a well-known proxy. The cheaper options may capture your information and will use for any other purpose. Generally, an average home user may not need a proxy anytime.

But maybe due to any virus attack from your computer, your IP has been blocklisted by some of the servers you were working on. One option is to change an IP or use a proxy for the time being until IPs are again allowed.