Four Core Functions of API Gateway: Connecting, Filtering, Governing and Integrating
Tags: apigateway, programming, devops, learning
Published: 2024-01-08 10:49:11

API has become an indispensable component in modern software development, facilitating seamless communication and data exchange across various applications. However, managing APIs, especially dealing with multiple sources, can be a challenging task. This is where the API gateway plays a crucial role, providing a comprehensive solution for connecting, filtering, governing, and integrating APIs.

In this article, we will delve into the four core functions of API gateway and discuss how they contribute to building a robust and scalable API ecosystem.

![Four functions of API Gateway](https://static.apiseven.com/uploads/2024/01/08/dxcuY3uS_4-core-functions-1.png)

## 1. Connecting

The first core function of the API gateway is to connect APIs from different sources, including on-premises, hybrid-cloud, and multi-cloud environments. This ensures that APIs are easily accessible and available for various applications. It also offers a unified management interface for both North-South and East-West traffic, facilitating efficient routing of API requests.

Additionally, the API gateway provides proxy, parsing, and transcoding capabilities for L7 (application layer) and L4 (transport layer) protocols. This feature enables APIs to communicate using different protocols such as HTTP, HTTPS, TCP, and UDP.

## 2. Filtering

The second core function of the API gateway is filtering, involving the application of various policies to control access, ensure security, and monitor performance. This function is crucial for protecting APIs from unauthorized access and ensuring the security of exchanged data.

API gateways like [APISIX](https://api7.ai/apisix) and [API7 Enterprise](https://api7.ai/enterprise) offer a range of open-source and commercial plugins for enforcing [policies](https://api7.ai/blog/api-gateway-policies) such as [authentication](https://api7.ai/blog/api-gateway-authentication), security, [observability](https://api7.ai/blog/apisix-transforms-logs-for-observability), and serverless computing. These dynamic [plugins](https://docs.api7.ai/hub) enable users to modify routing, upstreams, SSL certificates, and other policies in real-time.

## 3. Governing

The third core function of the API gateway is governing, and managing the full lifecycle of APIs to ensure availability, reliability, and scalability. Governing also ensures that APIs adhere to specific standards and policies, making them easier to manage and maintain.

APISIX provides governance features such as [canary release](https://api7.ai/blog/automate-canary-release-decisions-kubernetes-cluster), blue-green deployment, circuit breaking, [rate limiting](https://api7.ai/blog/rate-limiting-in-api-management), and health checks. These features ensure continuous monitoring of APIs, quickly detecting and resolving any issues.

![APISIX and API7 Enterprise Connects the World](https://static.apiseven.com/uploads/2024/01/08/KlMWUORo_%E5%9B%9B%E5%A4%A7%E5%8A%9F%E8%83%BD1.png)

## 4. Integrating

The fourth core function of the API gateway is integrating, involving the seamless integration of APIs with other applications, services, and tools for data exchange and workflow automation. Integrating makes APIs more accessible to developers, facilitating the creation of new applications and services.

[API7 Enterprise](https://docs.api7.ai/enterprise/introduction) offers out-of-the-box plugins by integrating with over 100 open-source projects and SaaS products, streamlining the integration process and reducing time and effort. API7 Enterprise also supports various standards, such as xDS, Gateway API, and OpenAPI, providing a common language for describing APIs and simplifying the development and consumption processes.

## Conclusion

In conclusion, API management is a critical function in modern software development, enabling organizations to build a powerful and scalable API ecosystem. The four core functions of the API gateway—connecting, filtering, governing, and integrating—provide a comprehensive solution for managing APIs.

These functions ensure that APIs are accessible, secure, reliable, and integrated with different platforms and services. By adopting an API gateway, enterprises can streamline their API management process, reduce costs, and improve their overall software development workflow.