Typically, blocking malicious requests on a request-by-request basis is preferable than blocking by IP addresses. However, in some cases, using of IP blacklists is necessary.
These cases are:
- When one needs to reduce system load that caused by the analysis of malicious requests.
- When traffic processing in an asynchronous way.
- When some extra resources are not protected with WAF.
All methods have advantages and disadvantages.
The most resource-intensive method. However, it allows customizing the message that the user sees when the request is blocked.
This method does not allow you to configure the error message, but it less affects server performance.
This method does not create absolutely any load on the server but requires additional integration of blacklist and firewall.