It is common to experience confusion when differentiating between Load Balancers, API Gateways, and BFFs. However, straightforward analogies can often clarify their distinct roles.
Load Balancers
Imagine a busy restaurant with several waiters. When you arrive, a host or hostess assesses the crowd and guides you to a waiter who will serve you efficiently. If a waiter is too much busy or unavailable, the host directs you to another one, ensuring a smooth experience.
Similarly, a Load Balancer operates in the digital world. It efficiently distributes incoming online requests across various servers, ensuring no single server is overwhelmed. If a server fails to serve the requests, the Load Balancer quickly reroutes the requests, maintaining uninterrupted service.
API Gateways
Consider an event, like a music festival, with different stages hosting various performances. As an attendee, navigating to your preferred stage can be confusing. Here, information booths act like coordinators, guiding you to the right stage based on your interests.
In the application domain, an API Gateway performs a similar coordinating role. It directs incoming requests to the appropriate services within an application. Additionally, it handles various critical tasks like authentication, rate limiting, and caching. An interesting point to note is that some advanced Load Balancers can double as API Gateways.
Backends for Frontends (BFFs)
Think of a university with different departments (like Engineering, Arts, and Sciences), each offering tailored courses and resources to its students. The administration ensures that each department’s specific needs are met, from specialized laboratories for engineers and art studios for arts students.
In the tech world, BFFs play a similar role. They act as specialized coordinators for different types of client-side applications (like web apps, mobile apps, or external systems), ensuring that each type receives the appropriate resources and services tailored to its unique requirements.
Whether you have previously engaged with Load Balancers, API Gateways, or BFFs, understanding their distinct functionalities can enhance your experience in managing or interacting with complex applications.
Reverse Proxy
Imagine a large art gallery with various themed rooms displaying different styles of art. As a visitor, finding the specific art piece or style you’re interested in could be daunting. In this scenario, the gallery guides act as reverse proxies. When you arrive, instead of wandering, you tell a guide what you’re looking for. The guide then leads you directly to the artwork or room that matches your interest.
Like these guides, a reverse proxy server receives requests from visitors (clients) and directs them to the appropriate art room (backend server). After the server processes the request, the reverse proxy returns the artwork’s view (the server’s response) to the visitor, making it seem as though the guide (proxy) provided the information directly. This process not only makes the visitor’s experience smoother but also helps manage and secure the flow of people within the gallery, ensuring an orderly and efficient visit.
The reverse proxy receives requests from clients, forwards them to appropriate backend servers, and then delivers the server’s response back to the client. To the client, it appears as though the proxy itself fulfilled their request. This setup prevents direct interaction with the main server, akin to guests not directly contacting the event manager but going through the ushers.
Reverse proxies are often employed for load balancing, much like how ushers distribute the audience evenly across the hall to prevent overcrowding in one area. They can also be used for caching, akin to ushers remembering frequent guests’ preferences for quicker assistance in future events.
Understanding the distinct roles of Load Balancers, API Gateways, and Backends for Frontends (BFFs) and Reverse Proxy is important in the architecture of modern distributed applications. Each plays a unique part in ensuring efficient request handling, secure data processing, and optimal user experience.
While traditionally these functions might have required separate tools, the evolution of technology has seen the emergence of modern, sophisticated tools capable of supporting all these features in a more integrated manner.
In my upcoming article, I will explain some of these cutting-edge tools, exploring how they seamlessly mix and match the functionalities of Load Balancers, and API Gateways offering more streamlined and powerful solutions for distributed infrastructure.