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 memo

 describes the "System for Cross-domain Identity Management (SCIM)." SCIM is a companion document to the SCIM Schema memo and the SCIM Protocol memo.

Section 3.5: Shouldn't there also be a requirement for the secure transfer of attributes between A and B based on matters such as A trusting authentication results from B, a means to provide those authentication results securely to B, etc.? Essentially similar to what was presented in Section 3.3?

Section 3.6: Similar comment as for Section 3.5. There seems to be general security requirements missing for these two scenarios?

Section 4: I only glanced the Security Consideration sections referenced here, but they do seem adequate, and given that I don't see that this memo's Security Consideration section need to contain more information. Editorial suggestion: "only authenticated entity" -> "only authenticated entities".

-- Magnus