In the previous post, I clarified the difference between an API Gateway and a Service Mesh. However, another common question is the difference between an API Gateway and a Load Balancer. After all, both sit in front of the back end and direct incoming traffic. While that is true, they work in different ways and at different abstraction levels.
A Load Balancer directs traffic to different instances of the same type of asset. The simplest example is a cluster of servers. By means of an algorithm (eg. round-robin), as more connections are made, the load balancer balances the traffic across the different servers. This leads to gains in responsiveness and availability of services.
API Gateways are much more fine-grained. They are capable of directing traffic to specific API endpoints. While a Load Balancer directs incoming traffic to different instances of the same asset, an API Gateway directs traffic to different APIs.
These two tools can be used together. However, it’s also common for API Gateways to have load balancing embedded in their functioning.
