INT Council INT Council India Internet Engineering Society This document proposes a methodology for isolating the location and reasons for IPv6 Extension Headers blockage in a network where the operator has access to install products and run diagnostic tests on both the client and server. The client will be outside the Content Delivery Network (CDN) and the server inside the CDN. This document will discuss the testing and topology which need to be considered when testing using a CDN infrastructure. This document is a part of the Deep Dive into EH Testing set of documents.