This is a bis draft of the HIP (Host Identity Protocol) Architecture and because of that I focused on what’s changed (i.e., I reviewed the diffs from https://www.ietf.org/rfcdiff?url1=rfc4423&url2=draft-ietf-hip-rfc4423-bis-18). It’s still HIP but with a slightly expanded scope; it’s still Informational. 1. s4: The one place where I’ll step out from not looking at the old is a similar-ish recommendation that was in the RF4423: In this document, the non-cryptographic forms of HI and HIP are presented to complete the theory of HI, but they should not be implemented as they could produce worse denial-of-service attacks than the Internet has without Host Identity. Should the should not be a SHOULD NOT? 2. (none security) s4.4: Is the paragraph about IPv4 vs IPv6 vs LSI really necessary? I.e., is this yet another thing that folks are going to use to not transition to IPv6? 3. s11.2: Isn’t an additional drawback the need to have a HIP-aware firewall?