Firewall
A firewall is a security system that filters data traffic to and from a website according to fixed rules and blocks harmful access before it can cause damage.
For websites, the Web Application Firewall (WAF) is particularly relevant. It checks incoming requests for typical attack patterns such as SQL injections, cross-site scripting, or automated login attempts and blocks suspicious requests before they reach the application. It works with rule lists and, in some cases, with machine learning systems that recognize unusual behavior, such as thousands of requests from the same IP address in a short period of time.
Example: A firewall registers 40.000 login attempts within one hour from changing IP addresses, a classic brute-force attack on the WordPress login. The rule automatically blocks the affected addresses for 24 hours; the actual website remains accessible to regular visitors without delay.
Make sure your hosting includes a server-side firewall, and for WordPress, supplement it with a security plugin that limits login attempts. Occasionally check the firewall logs to identify recurring attack patterns and tighten rules accordingly.
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