Azure’s regional Web Application Firewall (WAF) running on Application Gateway now supports rate-limit custom rules. Rate-limiting enables you to detect and block abnormally high levels of traffic destined for your application. By using rate limiting, you can mitigate many types of denial-of-service attacks, protect against clients that have accidentally been misconfigured to send large volumes of requests in a short time period, or control traffic rates to your site from specific geographies.
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