These are the presentation slides from “VoIP Wars: Return of the SIP” as presented at Defcon 21 in Las Vegas.
You can download it from the following link: https://packetstormsecurity.com/files/download/122690/Return_of_the_SIP-3.5.pdf
Source: https://packetstormsecurity.com/files/122690/VoIP-Wars-Return-Of-The-SIP.html