Sieve heralded as spam beater

The Internet Engineering Task Force (IETF) has developed a new way to filter spam which is rapidly gaining industry support.

Called Sieve, the filtering technology is not tied to any particular operating system or email architecture, and is winning support from vendors such Vircom, Sun Microsystems and Sendmail.

Sieve is a multi-vendor effort that provides a universal way for users to create filters for sorting, deleting and forwarding emails before they enter an in-box.

According to Tim Showalter, author of the Sieve document and a member of the technical staff at Mirapoint, the language is powerful enough to be useful, but limited in power in order to allow for a safe server-side filtering system.

"The intention is to make it impossible for users to do anything more complex and dangerous than write simple mail filters, along with facilitating graphical user interface-based editors," he said.

Sieve can be deployed to filter out spam, but the commands can also be used to redirect mail to other mailboxes based on mail content, and return bounced messages selectively depending on the type of email received.

While Microsoft and Lotus have yet to support Sieve, Sun's One Messaging Server supports the filtering language, and messaging server developer Vircom's anti-spam capabilities come from its open source scripting which is based on the Sieve scripting language.

The basic concepts for Sieve have been discussed since the early 1990s and, as part of Carnegie Mellon University's Project Cyrus, the first formal specifications were mapped out in 1995.

As of January 2001 the language is defined in the IETF Proposed Internet Standard, RFC 3028.