What is AWS elb?

AWS Elastic Load Balancing (ELB) is a highly scalable and fully managed load-balancing service provided by Amazon Web Services (AWS). It helps distribute incoming traffic across multiple targets, such as Amazon EC2 instances, containers, IP addresses, and Lambda functions, to ensure high availability, fault tolerance, and scalability of applications.

One of the primary benefits of AWS ELB is its ability to automatically distribute incoming traffic across multiple targets within a single Availability Zone or across multiple Availability Zones, allowing applications to handle varying levels of load and traffic spikes efficiently.

AWS ELB offers three main types of load balancers to serve different use cases:

1. Classic Load Balancer (ELB): This is the original type of load balancer offered by AWS. It operates at both the connection and application layers, making routing decisions based on IP address and port information as well as HTTP/HTTPS request content. Classic Load Balancer is suitable for applications that require basic load balancing capabilities.
2. Application Load Balancer (ALB): ALB operates at the application layer (Layer 7) of the OSI model and provides advanced routing and load balancing features. It supports content-based routing, path-based routing, host-based routing, and routing based on HTTP headers. ALB is ideal for modern microservices architectures and containerized applications.
3. Network Load Balancer (NLB): NLB operates at the transport layer (Layer 4) and is designed to handle extremely high volumes of traffic with low latency. It provides ultra-high throughput, and low latency, and supports static IP addresses for the load balancer. NLB is suitable for applications that require high-performance, low-latency load balancing, such as gaming, media streaming, and financial services.