Realtime blackhole lists (RBLs) are lists of servers that are either:
Most spam comes from dynamic IP customers whose boxes have been compromised and turned into open relays. By blocking these ranges from sending us email, we are mitigating a very large amount of spam.
Unfortunately, no spam catching system is 100% effective and occasionally we will come across people who use direct MX delivery from dynamic ranges; if these dynamic ranges are on RBL’s and the receiving mail server is using an RBL then this mail will be bounced by the receiving server.
In this situation, we would advise them to use their ISPs smart host instead. As spam becomes an ever increasing problem, more and more ISPs are going to start blocking dynamic pools so sending directly from a dynamic IP range is going to become less reliable (especially when systems like SPF are more widely used).
If you are having difficulty sending directly from your internet connection, Pulsant customers should send through mail.lumison.net.
We are currently protecting our customers from spam by using the following RBLs with the best reputations for accuracy:
Lumison does not use either MAPS or ORBS to block incoming mail as they are not totally reliable methods for blocking spam. Often genuine e-mail will be blocked by their lists, causing severe disruption to people and businesses.