Spamhaus Provides Answers: Part 3
This is part of an ongoing series in which Steve Linford, chief executive of anti-spam organization Spamhaus, agreed to field questions from Magill Report readers, who submitted more than 60.
The rest of this post is from Spamhaus:
26. What qualifies a domain for listing on the DBL? How is this different from listing the sending IPs instead on the SBL or CSS lists.
DBL listing is an automated process based on our proprietary heuristics. We can also make manual listings based on our investigation but those are a tiny fraction of the DBL zone. Filtering based on IPs and domains, as opposed to just one or the other exclusively, provides our clients with better protection against spammers who change either domain or IP, or both.
27. What business hours do Spamhaus employees work? Or, what is the best time to reach out to Spamhaus?
There are Spamhaus people all around the world, they do Spamhaus work as their schedule permits, and someone is always on watch, 24-7-365. It's been like that for over ten years and that remains into the foreseeable future. We generally respond to SBL removal requests within 24 hours, and email is how to reach us for that.
28. Will Spamhaus ever engage in a phone-call with Marketers?
The Spamhaus team communicates and collaborates via email, and that's also the way we prefer to be contacted. All SBL listings are resolved exclusively by email. That gives us and you a written trail of what is said, and it allows the SBL team to monitor and review its work.
29. What information must be collected in order to provide evidence that a subscriber opted in to receive a commercial email?
Most systems log email address, connecting IP, timestamp, and origin of the subscription (where the address was collected). Name and other personal info may also be collected. That's all good for your own use, but all such evidence can also be forged so it really doesn't help in resolving an SBL. Besides, we understand that you may not be able to share private information. The important thing to show us is not the historic logs, although they might help in some case, but a documented process of address acquisition, for example a process where we could confirm a subscription for our own test address.
30. If an ESP sends mail for multiple clients on a shared range of IP addresses and uses a shared sending domain, what is the best way to work with Spamhaus to resolve a block listing issue for an offending client while maintaining service for the rest of the clients on the range?
31. If an ESP sends mail for multiple clients on a shared range of IP addresses and the sending domain for each is a separate sub-domain, what is the best way to work with Spamhaus to resolve an issue for an offending client while maintaining service for the rest of them?
In both cases, read the SBL listing first to understand the problem, then contact SBL-removals as soon as possible to explain the situation. We know about mixed mailstream IP ranges, and if you've suspended the problem part of the stream so that our users won't get the spam (including clearing your outbound mail queue) we can usually work with you to quickly resolve the listing. Of course, we expect the spam to stay stopped (that may entail a wide range of solutions).
As far as sending domains, whether shared or subdomains, provide all the transparency you possibly can up front, publicly. Domain whois records identifying the sender, proper rDNS, fDNS resolving back to your IPs, and IP whois records reflecting your control of the range are good indicators of responsibility.