It has been a while since I last compiled our own ORF statistics using the Reporting Tool and what I am seeing is that SURBLs are taking over DNS Blacklists.
Is it just us, or are SURBLs really taking over? You can check your statistics in the Test / Summary section of any ORF report created with the ORF Reporting Tool.
UPDATE: Actually, there’s an explanation for this. Recently we switched to all-On Arrival filtering on our server and that means SURBLs are tested earlier than DNSBLs (see General Information / Test Order and Priority in the ORF Help), hence the more emphasized role for SURBLs.
That does not change the fact that SURBLs alone do a great job. ORF cleans up the the traffic step by step and 30% of what’s reaching SURBLs is cleaned up by them, leaving behind a much more legitimate traffic for DNSBLs, which cleans up another 8%.