My mistake in quoting. The IP was 192.168.1.30, a LAN address.
-------- Original Message -------- On Sep 21, 2021, 19:25, Dave Funk < [email protected]> wrote: On Tue, 21 Sep 2021, Bill Cole wrote: > On 2021-09-21 at 12:25:30 UTC-0400 (Tue, 21 Sep 2021 10:25:30 -0600) > Grant Taylor <[email protected]> > is rumored to have said: > >> But why the penalty for using non-public addresses* in a Message-ID: string? > > Empirical evidence. The use of a non-public address in a Message-ID > correlates to a message being spam. In my experience, so does using an IP > literal of any sort in a Message-ID, but that may be an idiosyncrasy in my > mail. > >> I was not aware that Message-ID had any requirements that the content had to >> mean anything beyond being syntactically correct. As such I would expect >> private / non-globally routed content to be allowed. After all, isn't the >> purpose of the Message-ID to be a universally unique identifier? If so, why >> does it matter what the contents is as long as it's syntactically correct? >> What am I missing? > > Private IP addresses in general cannot specify globally unique devices > (consider 127.0.0.1 or the very-popular 192.168.1.1) and therefore a > Message-ID using an IP literal as the RHS part with a non-public IP cannot > assure uniqueness. That is valid for Private IP addresses. However "[IPv6::ffff:193.168.1.30]" is the representation of IPv4: 193.168.1.30 which is a Public IP address, thus that 'hit' is in error. This should be considered a parsing bug. -- Dave Funk University of Iowa <dbfunk (at) engineering.uiowa.edu> College of Engineering 319/335-5751 FAX: 319/384-0549 1256 Seamans Center, 103 S Capitol St. Sys_admin/Postmaster/cell_admin Iowa City, IA 52242-1527 #include <std_disclaimer.h> Better is not better, 'standard' is better. B{
