MailMarshal claims 99.5 percent spam detection

Stephen Withers
Wednesday, 16 January 2008 06:00

Business IT - Technology

Marshal claims the latest version of its MailMarshal SMTP multi-layered anti-spam product consistently blocks over 99.5 percent of unwanted messages.

MailMarshal SMTP 6.4 now includes Cloudmark's Authority signature-based technology to help provide high spam recognition rates, even with foreign-language spam. This approach identifies most spam without imposing a heavy load on the server.

According to company officials, the false positive rate is less than 0.001 percent. This is achieved in part through the use of IP reputation services in conjunction with an adaptive whitelist, so messages from trusted sources should not be blocked in the event that the sending server finds its way onto a blacklist.

"IP Reputation services and real-time blacklists are an excellent way to block spam, but occasionally they blacklist a legitimate company," said Bradley Anstis, vice president of products at Marshal.

"Our unique and automatic adaptive whitelist system ensures that if a legitimate sender has been blacklisted the message will still be delivered. However, to ensure protection, such emails are not automatically sent to the recipient until they pass through the additional layers of defence in Marshal's Defense-in-Depth Anti-spam Engine."

Other layers use heuristics to identify previously unknown spam, URL recognition of websites associated with spamming, and user-defined policies including custom blacklists.

Other improvements in version 6.4 include more flexible quarantine management, RSS notifications, improved pornographic image detection, and a centralised update mechanism.