Hello Kathleen, thanks for the review.
> 1. I'm not clear on one of the bullets in section 3, > o HNCP nodes MUST use the leading 64 bits of MD5 [RFC1321] as DNCP > non-cryptographic hash function H(x). > > Is this meant to use a message digest (RFC1321) or a cryptographic hash > for authentication (RFC2104)? If it's the former, can you make this more > clear in the bullet? If it's the latter, can you update the reference > and the number of bits to use for truncation is 80 for the minimum. You > do explicitly mention HMACs later on for PSKs using SHA256, so maybe the > reference is correct and the wording should just be a bit more clear? I have staged this text now: HNCP nodes MUST use the leading 64 bits of the <xref target="RFC1321">MD5 message digest</xref> as the DNCP hash function H(x) used in building the DNCP hash tree. I hope that makes it more clear, that the hash is only used for comparison and to detect changes, not as a form of signature or authentication. > 2. Can you explain why DTLS is a SHOULD and not a MUST? The bullet in > section 3 reads as if this is for use, not implementation. Is there a > MUST for implementation (I didn't see one, but maybe I missed that)? The basic idea behind the SHOULD is that there may be cases where either physical security of links (e.g. cables) can be ensured or link-layer security such as WPA for WiFi is present. In these cases (e.g. some sort homenet wifi repeater) the DTLS would be redundant. In the Security Considerations sections we currently have a requirement: On links where this is not practical and lower layers do not provide adequate protection from attackers, DNCP secure mode MUST be used to secure traffic. which should ensure that devices MUST use HNCP security over both physically and link-layer-wise unsecured links. I guess this could be reflected in the DNCP profile section as well if that makes it more clear. Would that work better or do you have something different in mind? > > Could you add a reference to RFC7525 to help with configuration and > cipher suite recommendations? This could be in section 12, security > considerations. Staged for next revision. Cheers, Steven _______________________________________________ homenet mailing list homenet@ietf.org https://www.ietf.org/mailman/listinfo/homenet
