Written by Tom on Tuesday 12/12/06
There has been a significant increase in SPAM in the last couple of months. We all know that clear text email addresses are easy fodder for the netbots. The increase of SPAM has been blamed on a virus called 'SpamThru' which is a spam-sending Trojan for more details refer to Aggressive Botnet Activities Behind Spam Increase. Most email addresses are havested via netbots here are some common methods from the net to make life for the netbots differcult.
1. 'captchas': These are those nasty images that one must copy to verify that a human is requesting a login/contact. Pro's: They do offer a level of protection. Con's: Some of them are differcult to read.
2. Instead of a captcha display an image that the user must identify, a rat or pony etc. Varient: Display a grid of pics and get the user to pick three that are the same as proposed by http://www.kittenauth.com/. Or ask a question that requires an answer.
3. An editor of Slashdot suggest "So far I have been successful by using a session variable that is set when the form is requested via http get. If the submitted form doesn't have the session variable set, I dump the email and return a bogus error message."
Hopes this helps in the war against SPAM.
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