I am an assigned INT directorate reviewer for draft-ietf-httpbis-alias-proxy-status. These
comments were written primarily for the benefit of the Internet Area Directors.
Document editors and shepherd(s) should treat these comments just like they
would treat comments from any other IETF contributors and resolve them along
with any other Last Call comments that have been received. For more details on
the INT Directorate, see https://datatracker.ietf.org/group/intdir/about/.

Major Issues:

I am a bit concerned that there is no discussion about the potential scope for either domain names or IP addresses. What happens if a proxy sits behind a NAT? Does the NAT now need an ALG to convert private IP addresses to global ones? What about a situation where the proxy sits behind a firewall utilizing split DNS?