Summary: No issues found 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 describes a new field, somewhat disturbingly called "key" (in that it has nothing to do with a cryptography key) which is an extension to Mobile IP that allows specification of a specific GRE tunnel, allowing (care of address, home address, and home agent address) not to need to be unique across VPNs. As they rightly point out, this does not introduce new security issues. Radia