ALB Average connection duration - how does it work with websockets?

Hi Martin,

Handling a large number of persistent WebSocket connections can indeed be costly with AWS Application Load Balancer (ALB). The pricing for ALB is based on Load Balancer Capacity Units (LCUs), which take into account new connections, active connections, processed bytes, and rule evaluations. This can add up quickly, especially with long-lived connections.

Given your scenario, where connections remain open for months, the Classic Load Balancer (CLB) might be a more cost-effective option. CLB pricing is based on the number of hours the load balancer is running and the amount of data transferred1. Since CLB does not charge based on the duration of connections, it could potentially lower your costs significantly.

However, it’s important to note that CLB is considered a legacy service and might not support some of the advanced features available in ALB, such as content-based routing and enhanced security features. If your application doesn’t require these advanced features, CLB could be a suitable choice.

Please find these sources: https://aws.amazon.com/elasticloadbalancing/pricing/ https://www.cloudzero.com/blog/aws-alb-pricing/