Knowing the difference b/w ALB and NLB is important because they serve different purposes and affect how well your app performs. ALB is best for web traffic, while NLB is better for fast network traffic. Here’s a simple comparison that may help you to understand.
| Feature |
Application Load Balancer (ALB) |
Network Load Balancer (NLB) |
| Layer |
You will find it operates at Layer 7, meaning it can understand web content |
You will notice it works at Layer 4, focusing only on IP addresses and ports |
| Best for |
This type is great for handling web traffic (like HTTP/HTTPS) |
This type is ideal for fast network traffic, such as TCP, with very low delay |
| Routing |
You can configure it to route based on URLs, paths, or headers, making it flexible with web requests |
This type routes directly based on IP addresses and ports |
| Speed |
You can expect good speed for web apps, but it may add slight latency |
You will experience very fast speeds with minimal latency, perfect for time-sensitive traffic |
| Target Types |
You can use it with EC2 instances, IP addresses, and Lambda functions |
You will primarily use it with EC2 instances and IP addresses |
| Health Checks |
You will find it uses HTTP/HTTPS health checks to ensure web components are working well |
This type uses TCP health checks for a straightforward connection check |
| Ideal Use |
This type is best for websites, apps, or microservices needing advanced routing |
This type is great for real-time applications or gaming that need high-speed traffic |
| Cost |
You will typically find it cheaper for general web needs |
This type is higher in cost but optimized for performance in critical applications |
To have a clear idea of Elastic Load Balancers, check out this tutorial.
