When you build web applications or expose any data externally, you probably look for a platform where you can build highly scalable, secure, and robust REST APIs. As APIs are publicly exposed, there are a number of best practices for providing a secure mechanism to consumers using your API.
Amazon API Gateway handles all the tasks involved in accepting and processing up to hundreds of thousands of concurrent API calls, including traffic management, authorization and access control, monitoring, and API version management.
AWS WAF is a web application firewall that helps protect your web applications from common web exploits that could affect application availability, compromise security, or consume excessive resources.
As you make your APIs publicly available, you are exposed to attackers trying to exploit your services in several ways. The AWS security team published a whitepaper solution using AWS WAF, How to Mitigate OWASP’s Top 10 Web Application Vulnerabilities.