Antispam systems protect organizations against e-mail-related threats by identifying and removing junk mail and malicious messages. Some of the major threats, according to Radicati Group, include viruses, directory harvest attacks and denial of service attacks. Systems have broadened their approach to keep up with increased compliance needs and evolution of e-mails threats. Antispams come in three forms: software, appliance and hosted service. Buyers increasingly want a turnkey solution, analyst says, as they both decrease costs and simplify management.”]
Source: https://www.csoonline.com/article/2124845/toolbox–how-to-choose-your-antispam-strategy.html