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 ready with nits. In Security Considerations, I recommend: s/but further/but is further/. Then, I would change the second to last sentence in Security Considerations as follows: This complication, as mentioned in Section 4.4 of [RFC5890] and in Section 4 of [RFC6532], is that use of Unicode introduces the risk of visually similar characters which can be exploited to deceive the recipient. Kind regards, Adam