port scanner

Online Scanner is a free tool for detecting open ports on your device. It automatically detects IP addresses and scans your device, identifying open and vulnerable ports

Why port scanning is important

Websites can scan locally open ports and detect which ports are opened on a computer to learn which programs the user is running. We learned that Facebook, eBay and Amazon all use such technical means.

In computer science, a port is a communication endpoint. When an application runs on a computer, it opens a port, which corresponds to the address through which the application interacts with other applications.

For example:

  1. TeamViewer will open ports: 80, 443 and 5938 (TCP)
  2. RDP (Remote Desktop Protocol) will open port: 3389 (TCP/UDP)

Through port scanning, the website can help determine whether the user has performed operations not allowed by the platform through remote control of the VPS and other means, thereby banning the account.

How to enable port scan protection

Many fingerprint browsers support turning on port scan protection in the browser profile settings, which will prevent websites from detecting which ports you have open. This feature will prevent all ports from being scanned. But you can also whitelist a specific set of ports for websites to scan.

If some websites use Nmap for external scanning, then this feature will not take effect. However, as far as we know, due to local policy reasons, most websites do not use Nmap.