This informational document describes a tree-based CDN architecture (called TreeDN) addressing the scaling challenges of live streaming to mass audiences. The document points out three reasons why traditional multicast solutions did not receive widespread deployment and use. Afterwards the document argues that combining Source-Specific Multicast (SSM) [RFC4607] and Automatic Multicast Tunneling (AMT) [RFC7450] addresses all these challenges. Even though the document is fairly short, it occasionally feels a bit repetitive (e.g., first paragraph in Section 5) and sometimes a bit too much white paper marketing style. While the authors claim that TreeDN solves the chicken and egg problem of multicast deployments, it feels to me that this document was written in order to help solve the chicken and egg problem of TreeDN deployment. ;-) There is probably nothing wrong with this kind of informational documents marketing a certain architectural idea. However, as someone with a background in research, I would have loved to see some hard (quantitative) facts demonstrating that TreeDN is indeed a good solution outperforming others and not suffering from the general multicast challenges. Some descriptions of several successful deployments of the TreeDN idea would make this document stronger.