Office of Information Technology

image

How Does JSpamFilter Work?

First off, we are NOT filtering your e-mail. The product we are using is called "JSpamFilter," but we have only enabled tagging of suspected spam. All messages sent to you will be delivered. Those that the product suspects come from spammers will carry the [JSpamFilter] tag in the subject line. So if you feel that JSpamFilter is not doing an accurate job, you can just ignore the tags. But as a centralized system we do not have a means for an individual to opt-out of the tagging.

JSpamFilter only examines mail coming from off campus. Messages you send to others are NOT evaluated by the tagging system.

When a message comes in from off campus, JSpamFilter looks at the mail server sending the message. Since spammers mostly rely on hijacked e-mail servers which are open mail relays, the tagging system examines "blackhole lists" to determine if the mail server has been recently used to send spam or if it could be. These blackhole lists are independently maintained by anti-spam organizations who receive reports of spam from around the world, as well as actively probing mail server to see if they can be hijacked by spammers.

Why is my newsletter or other desired mail getting tagged?

  • As indicated above, the tagging system uses lists of compromised servers used for spamming. We do not control which servers get on these lists, nor can we petition these organizations to remove servers from the lists. Only the administrator of the e-mail server, after fixing the problem which allows spamming to occur, can do that. It is quite possible that legitimate organizations use inexpensive bulk e-mail services to send you the messages, and in turn these folks use spam houses. So you can choose to ignore the tags on these desirable messages -or- contact whoever is sending you the message and tell them their mail is being blackholed and that you would prefer they not support known spamming operations with their business.

Why is personal correspondence from another being tagged?

  • Similarly, if the organization this person send the e-mail from is on blackhole lists as having been used for spamming, then the mail is tagged. You should tell the sender that our anti-spam system is tagging their mail because their mail server is on one of the major blackhole lists for spamming. They should forward this to their e-mail server's administrator so that they can investigate and resolve the problem with their mail server that allowed spamming to occur.

So your saying is the other guys problem?

  • Basically, yes. Mail servers get on these lists because their are incorrectly configured to facilitate spamming. Each time you get a e-mail server administrator to plug up the holes in their server, that is one less server used by the spammers, and mail from them will eventually cease to be tagged as spam as the server falls off the blackhole lists.

Could the College's e-mail server be used for spamming?

  • No. We take great care in ensuring that the college's own e-mail server is impervious to being hijacked by the spammers. We have had a perfect record for the past 6 years in this area. Long before spamming became so prevalent. We frequently perform external tests of our mail server to ensure some hole is not opened up and perform blackhole searches to determine if any of the top 50 used blackhole lists have us listed.

OK, it seems like the tagging works... so why do I have to even see this junk mail?

  • Well, as we stated earlier, our goal was to leave it up to you to decide what to do. The College doesn't want to be in the business of deleting your mail without you knowing about it. Read the section on Filtering Your Tagged Messages to learn what YOU can do to take the tagging to the next level to totally eliminate spam from your mailbox.