According to a research conducted by Microsoft and published by the Radicati Group, the percentage held by spam in the total number of emails sent daily has been constantly growing since 2005. As a result, spam is expected to represent 77% of emails sent worldwide by 2009, amounting to almost 250 billion unsolicited emails delivered every day.

In a world where spam is bound to hold such an important position, methods of preventing it should also be given an increasing importance. Some of the easiest and most widely used prevention methods are host control solutions, Antispam applications and user education.

Host control is an easy way to ensure only valid emails reach end-users’ inboxes. Some well known methods are SPF (Sender Policy Framework), IP/email address-based lists (blacklisting, whitelisting and graylisting) and DKIM (Domain Keys Identified Mail Signature).

Source: Howto Forge

~LC