On Wed May 25 2005 10:35, Tony Finch wrote:
On Wed, 25 May 2005, Bruce Lilly wrote:
No. Being based in a comparison of IP addresses derived from a DNS RR
related to a domain name from EHLO/HELO, it suffers from the same
problems with that approach as SPF.
You said:
1. conflating sending and receiving
2. failure to understand fundamental properties of SMTP, e.g.
MAIL FROM remains unchanged during transport
3. attempts to assign a relationship between domain names
and IP addresses for sending email; there is no such
relationship
All apply (conflating sending/receiving, failure to account for SMTP
with mechanisms other than TCP, attempts to assign IP/domain relationship
for sending), and there was also "etc." which you conveniently failed to
quote, and that covers a slew of practical problems with EHLO/HELO.