7 different ways to detect Proxies

Posted on October 16, 2021 in Security • Tagged with proxy, proxy-detection, bot-detection, proxy-provider, anti-scraping • 12 min read

In this blog post, I demonstrate 7 different efficient ways how to detect a proxy server when the client is visiting a web server with a browser that has a proxy / VPN configured.


Continue reading

On the Architecture of Bot Detection Services

Posted on July 18, 2021 in Security • Tagged with Internet Bots, CAPTCHA, Bot Detection • 15 min read

There are unique challenges when developing a passive bot detecting system. In this blog article, I explain some of the obstacles that need to be overcome in order to detect advanced bots without presenting a CAPTCHA. I also explain how bot programmers can benefit from the architectural challenges that bot detection systems inherently suffer from.


Continue reading

API to Check if an IP Address belongs to a Datacenter / Cloud Provider

Posted on June 20, 2021 in Security • Tagged with API, IP-Address-Check, Datacenter, Cloud-Provider • 3 min read

For security reasons, it's often helpful to check if an IP Address belongs to a datacenter or cloud computing provider such as Amazon AWS or Microsoft Azure. Therefore, I have developed a simple public API that helps you to check if an IP address belongs to a datacenter / cloud provider.


Continue reading

Detecting Proxies and VPN's with Latency Measurements

Posted on June 07, 2021 in Security • Tagged with proxy-detection, anti-scraping • 10 min read

VPN's and Proxy Servers can be detected by comparing latencies measured with JavaScript in the browser with the corresponding latency of the TCP/IP handshake on the server.


Continue reading

Detecting Brightdata's (formerly Luminati Networks) Data Collector as a Bot

Posted on June 05, 2021 in Security • Tagged with proxy-provider, bot-detection, anti-scraping • 10 min read

In this blog article I demonstrate several bullet-proof ways how to detect Brightdata Data Collector as a bot without any doubt.


Continue reading

Detecting Datacenter and Residential Proxies

Posted on April 24, 2021 in Security • Tagged with Proxy Detection • 7 min read

Detecting proxys can't be that hard? Can it?


Continue reading