It is easy to enable and configure, and it works well with Apigee. You can also use Google Cloud CDN for caching along with these two solutions. This combination provides you a comprehensive solution that helps prevent DDoS attacks on your APIs as well as web applications hosted in the cloud or on-premises. 

Use reCAPTCHA Enterprise for API authentication

To strengthen security of your backend APIs, you could leverage reCAPTCHA Enterprise, which is an advanced version of the popular CAPTCHA technology that protects websites from bots by asking users to identify images containing street signs or traffic lights among other things
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