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 draft adds some new types verify connectivity and signal fault detection or fault status over a Pseudowire. It states that it introduces no new security issues beyond those defined in RFC 5085 and a couple of I-Ds on Bidirectional Forwarding Detection (BFD) and that seems to be correct. I see no security issues with this draft. On a non-security issue though, it appears that when doing IP encapsulation of BFD it sends to a randomly selected IP address from the loopback. I always thought that a loopback address MUST NOT appear outside a router or host. Has that changed or am I misunderstanding something about this draft? regards, Dan.