What is a proxy server?
A proxy (or proxy server) is a computer that stands between a user and the Internet. The user of the proxy sends all his or her internet traffic to the proxy server. The server then forwards the data to the final destination on the Internet. With a proxy, the identity and location of the user are (partly) hidden. In practice, proxies are usually used by people who want to visit a blocked site. Many companies and organisations also have their own proxies in order to create a closed company network. In this article we will give you more information about how a proxy works, what types of proxies there are and how secure they are.
How does a proxy work?
A proxy server is located between a local computer or a local network and a wider network like the internet. A proxy is usually a remote server: it works as an extra step in the online process. Without a proxy, your data travels the following route: as soon as you enter a website in your address bar, the information is first sent from your computer to your ISP’s router. It then goes on to the server of the website you are trying to reach. The response from the website is then sent back via the same route.
If you use a proxy, this path changes from computer to website. The user (i.e. you) connects to the proxy server, for example via a computer, laptop or smartphone. The server then sends this data to the final destination on the internet. As a result, the rest of the Internet does not get to see the user’s IP address, but rather the IP address of the proxy server.
A proxy server therefore transmits data. However, this is not the only thing. For example, a proxy also provides an extra layer of online security and there are various types of proxies that all have different functions. There are web proxies that work within your browser, but also proxies that can be installed on your router, so that all your data traffic is routed via the proxy. In the next section we will discuss the different functions that proxy servers can have.
Types of proxy servers
There are different types of proxy servers. First of all, a division can be made between proxy servers that are used by one user or a group of users and public proxy servers for large groups. With the second type of server, it is more difficult to identify a specific user, because so many people use the same IP address.
Transparent proxy In addition to the subdivision between different web proxies, you can also subdivide proxies based on how anonymous they make you on the internet. A transparent proxy server does not hide the user’s IP address. They identify themselves as proxy servers for websites and reveal the user’s original IP address there. These proxy servers are therefore usually used as caching proxies and not for anonymous browsing.
This type of proxy server identifies itself as a proxy server, but does not pass on the user’s original IP address. Anonymous proxy server provides reasonable anonymity for the user. You wouldn’t be able to use an anonymous proxy server to watch Netflix, because then Netflix knows you are using a proxy and won’t give you access to most parts of the website.
High anonymity proxy
This type of proxy server does not identify itself as a proxy server and does not pass on the user’s IP address. It is completely invisible to websites, while a ‘normal’ anonymous proxy can be detected. This proxy comes closest to a VPN in terms of anonymity, although it still lacks the security that a VPN offers.
Advantages of a proxy
Using a proxy server has several advantages. For example, a proxy sometimes affects your internet speed and online security. Many proxies also have extra functions: you can blacklist websites and bypass any other proxies and blockages. Finally, a proxy (partially) hides your IP address. You can read more about these advantages below.
Caching proxy servers store copies of websites you have visited. This stored information can improve your connection speed: if you surf to the same website again, the proxy will show you the stored copy, so that the website doesn’t have to reload completely. This also reduces the bandwidth you need when surfing.
Proxy servers can also be used to identify and avoid malicious code on websites. This way you have an extra layer of protection between you and the dangerous code. This reduces the risk of viruses and other digital infections. However, a proxy server does not protect you against all types of malware. We’ll tell you more about this later.
Hide your IP address
Many people are increasingly concerned about websites and companies that follow them online. Using a proxy helps to mask your online identity because it hides your IP address (unless you use a transparent proxy). Other parties only see the IP address of the proxy. Hiding your IP provides more online security and privacy: websites can no longer link your online behaviour to you. With a proxy you give less information about yourself to websites and other parties. If you prefer not to see personalized ads, a proxy server can arrange this for you to a certain extent.
Bypassing other proxies and blockages
Finally, a proxy server can bypass the restrictions of an online blockade or other proxy. As mentioned before, a company, school or even a government can block access to certain content using proxies. If you surf to these websites using your own proxy server, you can easily bypass these restrictions. For example, do you want to visit a news website that is blocked at your location? Then use a good proxy.
Your proxy must be set up correctly
Only a properly configured proxy server provides a reasonable level of privacy. Setting up the server is quite difficult and is not always under your control. The owner of the proxy needs to know what’s going on and then apply this knowledge to the proxy. This is the only way to ensure that your server is set up properly. In addition, the server needs to be maintained properly. This is not the case with many (free) proxy servers. The chance that a proxy server will leak your IP address (consciously or unconsciously) is therefore high.
Who manages the proxy server?
It is also very important that the administrator of the proxy server has good intentions. Many (especially free) proxy servers are managed by rogue parties who are targeting your personal data or are earning their money through advertisements. Keeping a server running is expensive and most owners try to win money by selling (private) user data, adding ads to websites or spreading malware and viruses.
Does the proxy allow HTTPS?
The use of a secure connection is very important. A proxy server does not add encryption to your internet connection. This makes the connection easy to eavesdrop on and your private data, such as your e-mail and login details, can be stolen by hackers and governments. The use of a secure version of websites (the HTTPS version) is therefore very important. Many proxy servers do not allow the use of HTTPS and therefore remove an essential security layer. Remember that sites with HTTPS are not automatically secure sites. HTTPS only indicates that the connection has been established in a secure manner. This can still mean that you ended up on a phishing website.
Since the use of open proxies is often related to the abuse of Internet services, a number of ways have been developed by system administrators to block open proxies from the use of services. IRC (Internet Relay Chat) networks, such as the blitzed network, automatically test clients’ systems for known types of open proxies. Similarly, a mail server can be configured to automatically test senders of e-mails for open proxies. Lists of various open proxies are available that are maintained on the Internet, such as those of the DNSBL.