Note: AWS Application Load Balancer can be used as a reverse proxy, but it only supports static targets (fixed IP address), no dynamic targets (domain name).

Is an ELB a reverse proxy?

As per my understanding we don't use ELB as a reverse proxy. If you would like capture client's IP address and using TCP listener then you would need to configure Proxy Protocol. However, if we are using HTTPS listener and want to know client's IP then you would need to use X-Forwarded header.

Is AWS alb a reverse proxy?

A load balancer is a type of reverse proxy. Its benefits including accepting traffic on specific ports, acting as a type of firewall, and prevents some kinds of attacks reaching the server.