Check if a proxy connection is detected using proxies can be important for a number of reasons, including security and compliance. However, detecting proxy usage isn’t always straightforward as the use of proxies can cause different HTTP header values. For example, proxies often add specific HTTP headers such as “X-Forwarded-For” and “Forwarded”, which can be spotted by analysing the request’s headers. Another method is to use blacklists to identify proxies, although these tend to be less reliable (especially in the iGaming industry where blacklists have been used to block legitimate players).

How to Check if a Proxy Connection is Detected

Firewalls are designed to monitor network traffic and check it against established security rules, rejecting or allowing packets accordingly. They also perform stateful inspection, ensuring that each packet is examined and evaluated in the context of its originating session. To determine if a connection is through a proxy, firewalls usually check the IP address and its port number. The ports are numbers that help network protocols direct data to the right service or application on a device. For instance, port 80 is designated for web browsing, while port 25 is reserved for email communication.

Additionally, firewalls can check whether the IP is listed in a published port list that is known to be used by open proxies. Finally, they can also check the type of protocol being used and the browser extension on the client to see if there are any giveaways such as multi-accounting or bonus abuse. If a user’s IP is found on a list, it can then be flagged to alert the security team that a potentially malicious user has been identified.