On 11/4/18 11:25 PM, Mik J wrote: > Do you know why, and particularly Microsoft, use very random IPs to send > mails. > In that way, they make greylisting not as reliable as it should be. We could > all use greylisting if google or microsoft would use the same 4 or 5 IPs to > retry sending the mails. > Google and Microsoft don't help to fight against spam.
The larger providers such as the ones you mention seem to have concluded that they need to send their mail from a large number of different IP addresses. As long as they actually use only addresses they have published as valid senders via their SPF info, we can let them bypass greylisting as described in the article (or referenced material) and determining whether any given message was spam becomes the task of other software such as your favorite content filtering. I would personally have preferred a clarification of the retry requirement to specify 'retry from the same IP address', which would have made greylisting *a lot* easier, but unfortunately that did not happen (cf https://bsdly.blogspot.com/2008/10/ietf-failed-to-account-for-greylisting.html). Cheers, Peter -- Peter N. M. Hansteen, member of the first RFC 1149 implementation team http://bsdly.blogspot.com/ http://www.bsdly.net/ http://www.nuug.no/ "Remember to set the evil bit on all malicious network traffic" delilah spamd[29949]: 85.152.224.147: disconnected after 42673 seconds.
