Reference: Notices-CloudMark

5 December 2006

After operating a generalized Mail Server (CommuniGate Pro) for several years, the volume of SPAM moving through the Mail Server and, indeed, on to our Client mailboxes has finally exceeded our own tolerance levels. We (RidgeStar) have also fallen victim to what we believe is inappropriate identification as a SPAM generation source (we think as a result of all the forwarded Email arriving for our clients).

As a result, we are today announcing the implementation of a Mail Server based Anti-SPAM/Anti-Phishing methodology intended to reduce the level of SPAM involved with RidgeStar Mail Services. This methodology is commonly known as CloudMark and involves the scanning of the messages as they travel through the Mail Server.

How Does this Work?

As each message arrives at mail.RidgeStar.com, our Mail Server software (Stalker's CommuniGate Pro) passes it through a Filtering process (the Cloudmark anti-SPAM and anti-Phishing routines). Each message is assigned a SPAM "score" that represents the likelihood that the message is valid or is likely SPAM.

The results of the Cloudmark scan is inserted into the message as a series of Headers similar to the following (higher scores have a higher potential for being spam):

X-Cloudmark-Score: 100.000000 [XXXXXX]
X-Alert: possible spam!
X-Color: red

What happens to Messages marked as SPAM?

The RidgeStar Mail Server will then process messages identified as SPAM in one of three ways (depending upon the individual SiteManager's direction):

1. SPAM Messages will have their Subject prepended with the literal string "[SPAM] ", but are delivered to the original recipient as addressed by the message (this is the standard approach for ALL Email messages handled by mail.RidgeStar.com)
2. Messages marked as SPAM will be automatically rerouted to the webmaster in a preselected folder and is NOT delivered to the original recipient. The WebMaster should periodically review these messages to make sure there are no obvious "false positives" and report any incorrect decisions made by Cloudmark.
3. Messages marked as SPAM are automatically deleted and NOT delivered to anyone

Why not delete them all automatically?

While Cloudmark has proven quite effective at identifying SPAM, there are occasions where it may identify a Message as SPAM that is not SPAM (a "false positive"). When this happens, it IS appropriate that we make sure the Cloudmark system is informed about the incorrect identification so they can correct their filtering process. Obviously, this cannot happen if no one periodically reviews the messages identified as SPAM by the Cloudmark filters.

It is RidgeStar's recommendation that each Site's webmaster periodically review the /SPAM folder associated with the webmaster account to check for any false positives that may exist. Contact your RidgeStar Account Representative and they will let you know what you need to do to report any false positives that you may find.

NOTE: Messages left on the RidgeStar Mail Server in the /SPAM folder more than 2 weeks is subject to deletion from the webmaster account at any time. If you are a Site WebMaster, please try to stay on top of this!!!

Do I still need a desktop based anti-SPAM tool?

It is our hope that the implementation of Cloudmark's filters on the RidgeStar Mail Server will eliminate much of the need for this. However, how your own Email client handles SPAM and how effective Cloudmark is at catching SPAM sent to you will be quite individual and, in fact, should help you decide if this is necessary or not.

Thus, the answer is a definite "maybe". If the Mail Server based Cloudmark logic is catching a sufficient level of SPAM and your own Desktop implementation is not necessary, then don't use it. On the other hand, if your own Desktop implementation is still providing functionality that you find useful, keep it.

Ultimately, this is very much an individual decision/choice.