What is an API Gateway?


What is an API Gateway?

An API gateway is a software feature that handles the task of handling and delivering client requests and bringing them the requested data along with other appropriate services. In layman’s terms, it serves as a single point of entry in an application to handle client requests and provide them along with the associated microservices via request routing, composition, and protocol translation. 

In eCommerce websites, when a user clicks on a specific product, they are presented with the product’s image along with price details, product description, reviews and similar suggestions.  Have you ever wondered what sorcery is behind the websites for bringing all the necessary details on one page with one click? Yes, it’s the API gateway. 

What does an API Gateway Do? 

An API gateway is the API management tool that resides between the client-side, and the backend database services. 

A well-built application aims to deliver the user the utmost and most satisfying experience. The application has to offer a wide range of services for such purposes. Since there will be a lot of services, each feature is designed to work as an individual entity so that any update or change in that particular service would not disrupt other services. This architectural design is referred to as microservices. 

API gateways handle the following functions with other APIs:

  • Cache management
  • Authentication
  • Monitoring
  • Logging
  • Service discovery
  • Protocol translation
  • Load balancing
  • Stabilisation 

Some other standard functions include security, routing, analytics, rate limiting and billing. 

Why Use an API Gateway? 

The purpose of API gateways is to deliver an all in one service by delivering accurate results along with appropriate microservices, thus making the user experience in the application more sophisticated and welcoming.

Each application’s client receives its own API with an API gateway. This works in a sort and filters way. If a client prefers only to see specific results, there are presented with their desired results alone.

Is this, however, the only function of an API gateway? Certainly not.

Organisations can use the API gateway to track and administer APIs independently. In order to assure security and evaluate failures, API gateways often contain monitoring features to identify and analyse requests and responses. The gateway is also used to control how other APIs behave, such as their processes, rules, and data flow.

Advantages and Disadvantages of API Gateway

Like any other software tool, API gateways too come with a set of advantages and disadvantages. They are:

Advantages of API Gateway

  1. API Gateways Provide Flexibility
  2. Easy Service Delivery 
  3. Enhances the Security Of  API Endpoints
  4. Extend the Functionality of Legacy Applications
  5. Reduces the Complexity of APIs
  6. Monitor Other APIs

API Gateways Provide Flexibility

API gateways are easy to configure. In a microservice-based architecture, developers can easily design the internal structure of the application in various criteria so that when a user accesses a specific service, they get sophisticated and appropriate services.

Easy Service Delivery  

API gateways ensure that API calls are delivered quickly by merging requests in a logical fashion and providing services for the requests on time. The flexible architecture saves bandwidth and coordinates the API procedure, resulting in a better user experience. This is why mobile applications appear to deliver services quickly.

Enhances the Security Of  API Endpoints 

The API gateway will operate as a security hurdle between the frontend services and the other microservices, ensuring that your essential API Endpoints are not revealed. It also defends your API against malicious cyberattacks, including SQL injections, DoS assaults, and other malevolent attacks that exploit the API’s flaws.

Extend the Functionality of Legacy Applications 

Even if legacy applications are out of date, Applications can try using API gateways to access their functionality instead of complete migration.

Reduces the Complexity of APIs

The goal of APIs is to deliver a certain service. However, other issues like access control, rate limiting, token authorization, and scaling can inhibit the quick process of APIs. API gateway takes care of such routine tasks, allowing the API to work along with its core functions.

Monitor Other APIs

Usually, when incorporating APIs into an application, firms also employ another monitor tool to monitor the service of the integrated APIs. Instead of adding a specific tool, API gateways can do this job much better. API gateways are much better than other monitor tools and can help perfectly identify the specific issue during the monitoring process.

Disadvantages of API Gateway

  1. Reliability and Resilience
  2. Security
  3. Complexity of APIs

Reliability and Resilience

API gateway is an all in one tool. It manages the delivery of service and other back-end services; it ensures security within the APIs and monitors their activities. However, even the slightest error in the operation of an API gateway will fail the whole application performance.

Hence firms should practice caution when adding new features and services to the application, as when one possesses a risk to the gateway, the whole application will lack the performance and delay service delivery. 


As we already stated, API gateway is a ubiquitous tool with a wide range of benefits. Maybe because it offers a multitude of services, including security, it is also the target of miscellaneous attacks from malicious sources.

When the security features of the API gateway are compromised, this can lead to severe data loss and performance loss. 

This is why firms should divide external interfaces from internal APIs and systems to define authentication and authorization parameters.

Complexity of APIs 

API gateway monitors and controls the delivery of features and services; even the slightest change in the system will have a profound effect on the performance of the API gateway.

If developers are to update the application with additional enhanced features, they must also be sure to update the API gateways.

The disadvantage is in a complex application with a plethora of microservices, the updating of the API gateway is a rather challenging feat. Creating and adhering to API and microservices design rules can aid in avoiding such issues.

Wrapping Up 

API gateway is an essential tool that developers incorporate into modern applications for the sake of optimised delivery and sophisticated performance of the application. 

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