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What is an API Gateway?

by Iwan Price-Evans on Security • June 8, 2022

An API gateway receives an API request and returns an answer, acting as a middle-man or "middleware" between an API consumer and one or many API services. API gateways handle common tasks across a system of API services, such as user authentication, rate limiting, real-time metrics, and more.

The purpose of an API gateway is to provide a consumer-facing facade for hiding the many backend applications in your internal network, which often could be a mixture of application codes and platforms: legacy monolithic applications on virtual machines, or containerized or serverless microservices

An API Gateway is the main point of control for managing access to APIs at scale.

API-gateway-architecture-facade-basicDo I Need An API Gateway?

An API gateway is essential to overcoming the API challenges of security and access, reliability and performance, and visibility and governance.

Without an API gateway, you would need to construct complicated routing rules and write custom code to handle all the various ways consumers and third-party systems might access your API. An API gateway makes accessing your APIs simple while also ensuring that they are secure, dependable, and consistent for all the ways consumed. 

Furthermore, a platform-agnostic API gateway will support API access no matter where or how your services are hosted along your transformational journey.

Learn More About Why You Need An API Gateway To Manage Access To Your APIs.

What Does An API Gateway Do?

An API Gateway will:

  • Defend against Common and Specific API vulnerabilities. API Protection typically comes in the form of Web Application and API Protection (WAAP) Firewall, highly specialized tooling specifically designed to protect web applications and APIs.
  • Prevent unauthorized access while allowing only authorized users to gain access to the information they require, with metered and fair-use usage enforcement if necessary.
  • Ensure quality of service (QoS) and service level agreements (SLAs). All tiers of consumers (e.g., "Bronze" and "Platinum") must receive acceptable SLAs by maintaining the highest degree of dependability and performance. Dynamic routing, service health checking, circuit breaking for poor performance or failed services, and much more are needed in an API Gateway.
  • Manage access to multiple API versions. As you expand your applications, new APIs will emerge and existing ones will be retired, however, consumers will still want to find all of your services in one place, understand how to use newer versions of an API, and transition to that at their own pace.
  • Provide a single entry point for external consumers regardless of the number or makeup of internal microservices. A microservice-based architecture might comprise tens or hundreds of heterogeneous services.
  • Provide insights into how your consumers employ your APIs, with real-time analytics and monitoring.
  • Manage API monetization strategies with access quotas and billing.
  • Facilitate secure internal communication between microservices in service mesh architectures.

What Are The Key Features Of An API Gateway?

The key features of an API gateway are:

  • API security
  • Connectivity and compatibility with multiple protocols
  • Flexible deployment in any server, data center, cloud, VM, or container
  • Elastic scalability
  • High availability
  • Management and orchestration
  • Automation
  • Developer integration

Is An API Gateway A Load Balancer?

Sometimes. Some load balancers and application delivery controllers such as Snapt Nova include API gateway functionality. API gateways that can distribute API traffic to multiple backends perform a load balancing function specifically for APIs.

Does Snapt Provide An API Gateway?

Yes. Snapt Nova provides API gateway, load balancing, and web app & API security on-demand from a centralized controller. Snapt Nova protects against the OWASP Top 10 API vulnerabilities and provides API access control, rate limiting, Quality of Service, and more.