IronPort Core MTA Architecture
Source: Cisco Systems
Email has become the dominant form of business communication, rivaling if not exceeding the importance of voice networks. Indeed, email has had such an extraordinary impact that, like the fax and AaTM, it's hard to imagine life before its widespread adoption over the last decade. The very power of the medium has also attracted a disturbingly large and growing number of security threats - spam, fraud, viruses, regulatory violations and intellectual property theft.