Site2 Hosted Exchange customers – did you recently notice more SPAM than usual??  Yeah, so did we.  And we did something about it!

In the world of SPAM fighting, our job is never done. Case in point, in early August we (and some of you) noticed an increased amount of junk email.  SPAM fighting can be like crime fighting – you need some investigative work to figure out where it’s coming from to stop it now and help prevent it in the future. As usual, this recent influx came from a variety of culprits. Thankfully, our Systems Engineers were on the case. Through a combination of new RBL’s and Greylistings we were able to stop the increased junk traffic and get your inboxes back to normal.

IT Jargon of the Month:

  1. RBL (or Real-time Blackhole List) is a list of IP addresses for computers or networks being used for spamming.  By using RBL lists, mail servers can reject messages sent from such locations.  “Blackhole” refers to a networking blackhole, a term for a link that drops incoming traffic instead of transmitting it normally.
  2. Greylisting is a way of protecting against SPAM by rejecting emails from a sender that the mail server doesn’t recognize.  SPAM is often sent from individuals or programs who are avoiding being “caught” and therefore only attempt to send an email once.  Greylisting works because if the email is sent from a legitimate mail server, it will attempt to resend a rejected email after a given period of time, thus suggesting that it is a valid email.  This isn’t foolproof, but it helps reduce the amount of junk.