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.
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
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.