Executive Guide to Email Security (whitepaper)

"As spam volume grows and email born viruses and worms become more threatening, the demand for comprehensive solutions has generated an unprecedented number of vendors entering the anti-spam market. With literally scores of vendors to choose from it is important to categorize providers by the type of approach they take to stopping spam and virus threats. There are two major categories of providers that follow conventional email security models. One category uses desktop anti-spam software while the other relies on server/gateway appliances or software." Source: whitepaper.informationweek.com