I have reviewed this document as part of the security directorate's ongoing effort to review all IETF documents being processed by the IESG. These comments were written primarily for the benefit of the security area directors. Document editors and WG chairs should treat these comments just like any other last call comments. This document is well outside my normal area of expertise. The claim in the Security Considerations section is that this document doesn't change the security properties of TRILL. This seems reasonable and I don't see any major issues with the document. Cheers Leif