API Gateway vs Load Balancer

API Gateway vs Load Balancer

An 𝗔𝗣𝗜 𝗚𝗮𝘁𝗲𝘄𝗮𝘆 acts as a single entry point for clients, handling request routing, composition, and protocol translation. It simplifies client interactions with microservices and offers features like rate limiting, authentication, monitoring, and more.

The main purpose of an API gateway is to provide a secure and consistent access layer for client applications. It can also perform various tasks, like rate-limiting requests, authenticating users, logging requests/responses, enforcing security policies, etc.

API Gateway Functions : The API gateway can provide many functions. Here are a few of the main ones

• Authentication — Authenticates incoming requests and verifies if the user has access to those resources.
• Authorization — Controls what data or services the user is allowed to access.
• Rate Limiting — Limits the number of requests that can be made within a certain time frame.
• Logging — Logs requests and responses to help with troubleshooting, debugging, and auditing.

These functions help ensure that only authorized users can access the resources they need and prevent malicious actors from overloading your system.

For example, in a mobile banking app, an API Gateway can sit between the app and different services like account details, transaction history, and currency exchange rates. When the app requests user account information, the Gateway routes this request to the appropriate service, handles authentication, aggregates data from different services if needed, and returns a consolidated response to the app.

𝗟𝗼𝗮𝗱 𝗯𝗮𝗹𝗮𝗻𝗰𝗲𝗿𝘀 are concerned with routing client requests across multiple servers to distribute load and prevent bottlenecks. This helps maximize throughput, reduce response time, and optimize resource use.

Load Balancer Functions : The primary role of a load balancer is to balance the load between two or more servers. It does this by monitoring the health of its backend servers and distributing traffic accordingly.

In addition, a load balancer can also provide other important functions, such as:

• SSL Offloading — Takes responsibility for managing encryption/decryption of HTTPS traffic.
• HTTP Compression — Compresses web pages to reduce the amount of data sent over the network.
• Content Caching — Stores frequently used content in a cache, so it can be quickly retrieved when needed.

For example, a load balancer can ensure that other requests are unaffected if one server fails due to a power outage. It can maintain multiple healthy servers in the pool to handle load, keep a user’s requests directed to the same server for consistent experience during an outage, and automatically reactivate and integrate recovered servers back into the pool.

Key differences :

API gateways focus on request management and microservice communication, while Load Balancers focus on traffic distribution and server load management.

API gateways operate at the application layer (L7), while Load Balancers can operate at both transport (L4) or application (L7) layers.

API gateways offer features like routing, rate limiting, authentication, service discovery, parameter validation, circuit breakers, and more. Load Balancers handle traffic distribution and failover.

An 𝗔𝗣𝗜 𝗴𝗮𝘁𝗲𝘄𝗮𝘆 𝗶𝘀 𝗜𝗱𝗲𝗮𝗹 𝗳𝗼𝗿 𝗺𝗶𝗰𝗿𝗼𝘀𝗲𝗿𝘃𝗶𝗰𝗲 𝗮𝗿𝗰𝗵𝗶𝘁𝗲𝗰𝘁𝘂𝗿𝗲𝘀 needing centralized API request management.

A 𝗹𝗼𝗮𝗱 𝗯𝗮𝗹𝗮𝗻𝗰𝗲𝗿 𝗶𝘀 𝗲𝘀𝘀𝗲𝗻𝘁𝗶𝗮𝗹 𝗳𝗼𝗿 applications requiring high availability, distributing traffic across multiple servers.

In summary, API Gateways manage and secure API calls, while Load Balancers ensure efficient traffic distribution.

Happy Reading!