Do Elastic IPs change network route for outgoing requests?

Question

I am wondering from a latency perspective if assigning an Elastic IP changes the route when I make an outgoing HTTP request?

Or is it only changing the IP the receiver "sees"?

Answer 1

There's no difference in latency. In both cases, you have a public IP address. The only difference is that if you use a default public IP address it's going to change if you stop your instance. With Elastic IP address, you're still going to have the same IP address.

From the documentation:

When you associate an Elastic IP address with an instance, it is also associated with the instance's primary network interface. When you associate an Elastic IP address with a network interface that is attached to an instance, it is also associated with the instance.

Which is the same way default IP addresses would be attached to your instance.