AWS Certified Developer – Associate — Question 63

An ecommerce application is running behind an Application Load Balancer. A developer observes some unexpected load on the application during non-peak hours. The developer wants to analyze patterns for the client IP addresses that use the application.
Which HTTP header should the developer use for this analysis?

Answer options

• A. The X-Forwarded-Proto header
• B. The X-Forwarded-Host header
• C. The X-Forwarded-For header
• D. The X-Forwarded-Port header

Correct answer: C

Explanation

The correct answer is C, the X-Forwarded-For header, as it contains the originating IP address of the client making the request. The other headers (A, B, D) do not provide this information; they relate to the protocol, host, and port respectively, which are not useful for identifying client IP patterns.