Aamir

Nov 30, 2023

Difference between Application Load balancer, Network Load Balancer, Gateway Load Balancer in AWS

Let's understand what is the difference between Application Load Balancer (ALB), Network Load Balancer (NLB), and Gateway Load Balancer (GLB) in AWS.

Before that let's understand what is load balancer:-

A load balancer acts as the “traffic cop” sitting in front of your servers and routing client requests across all servers capable of fulfilling those requests in a manner that maximizes speed and capacity utilization and ensures that no one server is overworked, which could degrade performance.

If a single server goes down, the load balancer redirects traffic to the remaining online servers. When a new server is added to the server group, the load balancer automatically starts to send requests to it.

ALB vs NLB vs GLB

Amazon Web Services (AWS) provides several types of load balancers to distribute incoming network traffic across multiple targets, ensuring high availability and fault tolerance. Each type of load balancer is designed for specific use cases. Here's a brief overview of the differences between Application Load Balancer (ALB), Network Load Balancer (NLB), and Gateway Load Balancer (GWLB) in AWS:

1. Application Load Balancer (ALB):

-> Layer 7 (Application Layer): ALB operates at the application layer of the OSI model.

-> Routing: It routes traffic based on content, allowing for more advanced routing decisions based on HTTP/HTTPS content.

-> Use Cases: Ideal for applications that require advanced routing features, such as microservices-based architectures, containerized applications, and those utilizing WebSocket or HTTP/2 protocols.

-> Features: Supports host-based and path-based routing, SSL termination, and integration with AWS services like AWS WAF (Web Application Firewall).

2. Network Load Balancer (NLB):

-> Layer 4 (Transport Layer): NLB operates at the transport layer, making it more suitable for handling TCP/UDP traffic.

-> Routing: NLB routes traffic based on IP protocol data, such as IP address and TCP/UDP port.

-> Use Cases: Ideal for scenarios requiring high-throughput, low-latency performance, and handling TCP/UDP traffic, such as gaming applications, IoT (Internet of Things), and applications that require static IP addresses for clients.

-> Features: Supports static IP addresses, preserves the source IP of the client, and handles TCP/UDP traffic.

3. Gateway Load Balancer (GLB):

-> Hybrid Load Balancer: GLB is designed for hybrid deployments that span on-premises data centers and the cloud.

-> Routing: It operates at the network layer and routes traffic based on IP protocol data.

-> Use Cases: Ideal for scenarios where you have a mix of on-premises and cloud resources and need a single entry point for your hybrid applications.

-> Features: Supports both internet-facing and internal load balancing, integrates with AWS Site-to-Site VPN and AWS Direct Connect, and provides centralized management for on-premises and cloud resources.

In summary, the choice between ALB, NLB, and GWLB depends on the specific requirements of your application, such as the layer at which you need to balance the traffic, the type of routing decisions you need to make, and whether you are working in a cloud-only or hybrid environment.

Thanks for Reading