IP Reputation and Sender Authentication have been important factors in delivery for many years. These twin principles, “Are you who you say you are?” and “How do you behave over time?” were developed as industry best practices to take a broader and more systemic look at how spammers and reputable senders behave. These were more useful than the blunt instruments of content-based filters, and more powerful than simple blacklists and whitelists.
Over time, however, IP Reputation has become a less-useful metric for ISPs to measure. We talk more about this in our blog posts:
Authentication can be challenging as well. SPF, once the industry standard, has had problems, which led to Domains Keys and DKIM. Now we’re even seeing protocols (DMARC) layered on top of DKIM. Many of our wiseTools were developed to help email administrators deal with these challenges.
More from our blog: