Guide: API Gateway Security in AWS Solution Architect

API Gateway Security is an important aspect of AWS Solution Architect. This guide will help you in understanding its importance, functionality, and tips to answer the exam questions.

Why it is important:
Security is a crucial factor for any application on the web. With AWS API Gateway, one can apply different layers of security like Resource policies, CORS, IAM policies, and Lambda authorizers thus reducing the risk of cyber threats. So, understanding API Gateway Security becomes vital for every Solution Architect.

What it is:
Amazon API Gateway is a service that acts as a 'front door' for applications to have access to data, business logic, or functionality from your backend services. API Gateway Security refers to the security measures and strategies applied to protect these APIs from threats.

How it works:
API Gateway Security works with multiple layers. Resource policies control whether a specified principal can invoke the API, Cross-origin resource sharing (CORS) controls how the API responds to requests from different origins, Identity and Access Management (IAM) policies control who can create, deploy, or manage an API, and Lambda authorizers determine who can access REST APIs.

Exam Tips - Answering Questions on API Gateway Security:
- Understand the basic terms like Resource policies, CORS, IAM and Lambda authorizers.
- Know how these security layers individually work and their utilization.
- Be aware of scenarios where multiple security measures can be applied together.
- Practice questions related to API Gateway Security.