One other question. How do you manage domain based reputation vs IP reputation. I'm trying to get by running a service off of Cloud provider IPs and they may rotate from time to time as VPSs rotate. Part of me feels that once my domain has enough reputation it should be fine. It does seem like some of the big providers work like this (Google seems to trust me now from any IP) but it seems that a lot of smaller providers rely on blacklists more as they don't see as much traffic to build reputation. How do blacklists handle domain reputation?
From our perspective, we don't link IP and domains at all at the moment, they are totally independent.
Because spam traps get very different traffic to a real mail server, you can make a lot of assumptions that would be impossible to do on a real mail stream.
So generally speaking, if your domain name isn't in the top million domains (and there are still some exceptions to this - but I'm not going to list them all here) and you hit one of our pristine traps (see my post about the different trap types) with a message containing your domain, that will usually cause the domain to be listed.
Other lists and spam filters will have their own methods for this.
My belief is that Google and Microsoft only use AI for this (which is a bit of a nightmare if it gets it wrong).
