Archive notice: This article was originally published on January 27, 2008. Links and embedded videos are preserved as part of the historical record.
Between 90 and 95 percent of all emails sent worldwide were spam. Berlin anti-spam firm eleven said the flood of unwanted mail had quadrupled during the previous year. Thomas Mandl, technical director at Austrian security company Ikarus Software, said the increase was commercial: even a 0.01 percent response rate remained profitable with 15 billion spam messages sent daily.
An industry had developed to detect, filter and block unsolicited messages. The spammers generally remained a step ahead, however, and a completely spam-free inbox was unlikely; security companies could mostly only limit the messages that actually reached users.
Germany’s eco association advised users to treat an email address like a secret number and never leave private addresses in plain text online, because harvester programs search the web for addresses. It recommended a separate address for registrations with web forums or online communities, so that address rather than the main one would collect spam.
For businesses, the message volume could strain IT systems and require technical upgrades. Mandl described technical and organisational approaches; charging for email had been proposed but was unlikely to work because much spam was sent through hijacked bot computers. Panda Software estimated that 85 percent of spam was sent through such machines and that around eleven percent of computers worldwide were infected. Filters, blacklists and whitelists offered different advantages and disadvantages.
Mandl cautioned about blacklists, whose operators could block whole IP ranges when spam came from one connection, disrupting legitimate communication. Whitelists were used as a countercheck but trusted hosts could still be compromised. SpamAssassin, a free open-source application with more than 500 configurable checks, scored incoming messages by spam probability and filtered them at a limit. For small and medium-sized businesses without an IT administrator, paid products from eleven, IronPort or Ikarus were recommended. Mandl said both high detection rates and low false positives were important.
Mandl did not believe email had ended yet, but said it would be dead if spam approached 100 percent. He called for providers to immediately block connections found sending spam, despite the difficulty that a customer with a hijacked machine would also lose service.
