Vulnerability Testing of RESTful APIs Against Application Layer DDoS Attacks

In recent years, modern mobile, web applications are shifting from monolithic application to microservice based application because of the issues such as scalability and ease of maintenance.These services are exposed to the clients through Application programming interface (API). APIs are built, integrated and deployed quickly.The very nature of APIs directly interact with backend server, the security is paramount important for CAP. Denial of service attacks are more serious attack which denies service to legitimate request. Rate limiting policies are used to stop the API DoS attacks. But by passing rate limit or flooding attack overload the backend server. Even sophisticated attack using http/2 multiplexing with multiple clients leads severe disruptions of service. This research shows that how sophisticated multi client attack on high workload end point leads to a dos attack.