Application Load Balancer (ALB)

An Application Load Balancer (ALB) is a Layer 7 (application layer) load balancing service, primarily associated with AWS, that distributes incoming application traffic across multiple targets, such as EC2 instances, containers, or Lambda functions. It operates at the request level, enabling…

Key facts

First appeared
2016
Category
technology
Problem solved
Application Load Balancer was created to overcome the limitations of its predecessor, Classic Load Balancer (CLB), especially in supporting modern application architectures. CLB primarily operated at Layer 4 (TCP) with limited Layer 7 capabilities, making it inefficient for microservices, complex routing requirements, and integration with container orchestration platforms. ALB addressed these by offering advanced content-based routing, WebSockets, HTTP/2 support, and native integration with diverse AWS compute services like Lambda and ECS/EKS.
Platforms
AWS Cloud

Related technologies

Notable users

  • Netflix
  • Siemens
  • Airbnb
  • Capital One
  • Epic Games