A company is building an application where IoT devices send measurements to AWS. The app will have millions of users. The IoT devices cannot perform DNS resolution. The company needs an EC2 Auto Scaling setup so devices can reach an application endpoint without relying on DNS. What is the most cost-effective solution?

The correct solution is to use a Network Load Balancer (NLB) because it provides static IP addresses, which is crucial for IoT devices that cannot perform DNS resolution. NLBs operate at Layer 4, offering high performance and low latency. Attaching an EC2 Auto Scaling group to the NLB ensures that the application can scale automatically to handle millions of users while maintaining availability. This is also the most cost-effective solution as it directly addresses the requirements without unnecessary additional services. Using an Application Load Balancer (ALB) with an NLB is incorrect because ALBs do not provide static IP addresses and are more expensive for this use case. AWS Global Accelerator is not needed as the primary requirement is static IPs, not global traffic optimization, and it would add unnecessary cost and complexity. While Global Accelerator does provide static IPs, the NLB alone fulfills the core requirement more cost-effectively.