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 how IPv6 is transported over Bluetooth Low Energy (BT-LE). As a proviso, I am not an expert in IPv6, 6LoWPAN, or Bluetooth. Still, this document seemed to be a clear specification of the intended subject matter. The Security Considerations section says that the security concerns are similar to those for IPv6 over 802.15.4. That makes sense, I suppose. I was happy to see that this document says "IPv6 over BT-LE SHOULD be protected by using BT-LE Link Layer security", whereas RFC 4944 (IPv6 over 802.15.4) does not include any normative language on using link layer security. Also, this document says that "Key management in BT-LE is provided by the Security Manager Protocol (SMP)", whereas RFC 4944 says that no key management is provided by 802.15.4. So this specification is apparently more secure that RFC 4944. That's good. So based on my review (admitting little knowledge of BT-LE), this document seems to be an improvement over the current state of the art for 6LoWPAN from a security perspective. And the overall level of security seems reasonable. I have no objection to the publication of this document. I did notice two typos: gateway^1s => gateway's respectively => respectively Thanks, Steve