Recent analyst estimates indicate that over 60 percent of the world’s email is unsolicited email, or “spam.” Spam is no longer just a simple annoyance. Spam has now become a significant security issue and a massive drain on financial resources. In fact, this deluge of spam costs corporations an estimated $20 billion each year in lost productivity.
Today there are a large number of solutions designed to help eliminate the spam problem. These solutions use different techniques for analyzing email and determining if it is indeed spam. Because spam is constantly changing, the most effective spam blocking solutions contain more than one of these techniques to help ensure that all spam, and only spam, is blocked.
The following is an overview of different spam blocking techniques.
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