You are designing a high-performance application that requires millions of connections. You have
several EC2 instances running Apache2 web servers and the application will require capturing the
user’s original source IP address and source port without the use of X-Forwarded-For. Which of
the following options will meet your needs?
Correct answer - "Network Load Balancer" : A Network Load Balancer functions at the fourth layer
of the Open Systems Interconnection (OSI) model. It can handle millions of requests per second.
After the load balancer receives a connection request, it selects a target from the target group
for the default rule. It attempts to open a TCP connection to the selected target on the port
specified in the listener configuration. Incoming connections remain unmodified, so application
software need not support X-Forwarded-For.
"Application Load Balancer" - One of many benefits of the Application Load Balancer is its
support for path-based routing. You can configure rules for your listener that forward requests
based on the URL in the request. This enables you to structure your application as smaller
services, and route requests to the correct service based on the content of the URL. For needs
relating to network traffic go with Network Load Balancer
"Elastic Load Balancer" - Elastic Load Balancing is the service itself that offers different
types of load balancers
"Classic Load Balancer" - Its a basic load balancer that distributes traffic. If your account was
created before 2013-12-04, your account supports EC2-Classic instances and you will benefit in
using this type of load balancer. The classic load balancer can be used regardless of when your
account was created and whether you use EC2-Classic or whether your instances are in a VPC but
just remember its the basic load balancer AWS offers and not advanced as the others