Understanding the Differences Between Application Load Balancer (ALB) and Network Load Balancer (NLB)!!

The primary difference between Application Load Balancer (ALB) and Network Load Balancer (NLB) lies in the OSI model layer at which they operate, their functionality, and use cases.

Application Load Balancer (ALB)

Layer: ALB operates at Layer 7 (Application Layer) of the OSI model.

Key Features:

1. Content-Based Routing: ALB can make routing decisions based on the content of the request. It can inspect the content of HTTP headers, paths, and cookies.
2. Host-Based and Path-Based Routing: ALB supports routing based on the hostname in the request URL and the path in the request URL.
3. SSL Termination: ALB can offload SSL decryption, freeing up resources on your application servers.
4. WebSockets and HTTP/2: ALB supports WebSocket and HTTP/2 protocols.
5. Target Groups: ALB routes traffic to one or more registered targets (such as EC2 instances, containers, and IP addresses) based on configured rules.
6. Monitoring and Logging: ALB integrates with CloudWatch for monitoring and provides access logs that capture detailed information about requests sent to your load balancer.

Use Cases:

• Web applications that require advanced routing mechanisms.