The Battle Against Spam

The MLISD/OISD Online Directory employs two different measures to counter spammers.

• We hide our addresses from spam-bots.
• We poison the spammers' lists, rendering them unsellable.

We hide our addresses from spam-bots by using a validator page. If a user is not logged in to our system, all email addresses will be replaced with "Click to Reveal" until the user has been validated. When that link is clicked, the validation page will appear. The user will then enter the code as seen in the image into the box below. Since these images can only be translated to characters by a human, spam bots cannot enter the correct code to pass the test. Once a user has been validated, they will be allowed to view email addresses until they close their browser. This is the passive approach to combating spam. Click here to learn more about CAPTCHA (Completely Automated Public Turing test to tell Computers and Humans Apart) method.

The active approach to battling spam is what we call a list poisoner. This method ruins the list that the spammer has collected by polluting it with fake addresses. We make this work by sending the spam-bot to a page containing hundreds of randomly generated email addresses and text. As the spam bot reads this page, it collects these fake addresses and proceeds to follow the links on the page, which will lead it to essentially the same page disguised by a different name. This sends the bot into an infinite loop since each new page sends it to the next page in the sequence and then starts over again. Every time a page is visited, a new throng of fake addresses is created, read by the bot and added to the list. By the time the spammer figures out what has happened, his once pristine list is now congested with garbage, much in the same way we find our inboxes as a result of their malicious efforts. Because of this, they will be unable to sell that particular list since it now contains far more junk addresses than real. This active approach will not only keep our addresses safe, but will also keep safe the addresses that were collected by the bot from other unsuspecting websites.