Richard Gowman and Eldon Sprickerhoff performed black-box analysis of Nortel Call Management VoIP implementations. Nortel VoIP infrastructure is widely implemented worldwide, but very little attention appears to be paid to its security issues, probably due to the fact that a proprietary protocol (UNIStim) is used. The presenters discussed the methods used to reverse engineer the protocol, specific attacks they developed, and how successful they were.