Network Load Balancer

You can load balance both TCP and UDP traffic, routing connections to targets - Amazon EC2 instances, microservices, and containers.

Network Load Balancer supports client TLS session termination. This enables you to offload TLS termination tasks to the load balancer, while preserving the source IP address for your back-end applications. You can choose from predefined security policies for your TLS listeners in order to meet compliance and security standards. AWS Certificate Manager (ACM) or AWS Identity and Access Management (IAM) can be used to manage your server certificates.

You can use SNI to serve multiple secure websites using a single TLS listener. If the hostname in the client matches multiple certificates, the load balancer selects the best certificate to use based on a smart selection algorithm.

Sticky sessions (source IP affinity) are a mechanism to route requests from the same client to the same target. Stickiness is defined at the target group level.

Network Load Balancer offers extremely low latencies for latency-sensitive applications.

Network Load Balancer preserves the client side source IP allowing the back-end to see the IP address of the client. This can then be used by applications for further processing.

Network Load Balancer automatically provides a static IP per Availability Zone (subnet) that can be used by applications as the front-end IP of the load balancer.

Network Load Balancer also allows you the option to assign an Elastic IP per Availability Zone (subnet) thereby providing your own fixed IP.

If there are no healthy targets registered with the Network Load Balancer or if the Network Load Balancer nodes in a given zone are unhealthy, then Amazon Route 53 will direct traffic to load balancer nodes in other Availability Zones.

In the event that your Network Load Balancer is unresponsive, integration with Route 53 will remove the unavailable load balancer IP address from service and direct traffic to an alternate Network Load Balancer in another region.

Network Load Balancer is integrated with other AWS services such as Auto Scaling, Elastic Container Service (ECS), CloudFormation, Elastic BeanStalk, CloudWatch, Config, CloudTrail, CodeDeploy, and AWS Certificate Manager (ACM).

Network Load Balancer supports long-lived TCP connections that are ideal for WebSocket type of applications.

Network Load Balancer uses the same API as Application Load Balancer. This will enable you to work with target groups, health checks, and load balance across multiple ports on the same Amazon EC2 instance to support containerized applications.

The Network Load Balancer is designed for application architectures in a single zone. If something in the Availability Zone fails, we will automatically fail-over to other healthy Availability Zones. While we recommend customers configure the load balancer and targets in multiple AZs for achieving high availability, Network Load Balancer can be enabled in a single Availability Zone to support architectures that require zonal isolation.