Open-source anti-spam specialist ASSP this week became the latest software developer to implement the Sender Policy Framework (SPF) anti-spam scheme.

Beta versions of ASSP with SPF support are currently being tested, and SPF is set to be included in the next version of ASSP, expected soon. SPF extends the Simple Mail Transfer Protocol (SMTP) and Domain Name System (DNS) so systems do not accept mail unless the computer sending it is listed in a new type of DNS record.

Some experts said this approach is very easy to set up and would reduce spam. One contributor to the ASSP project said in an online posting, "While [SPF is] not widely implemented, [it] would be a great way to tag incoming email as illegitimate. Hotmail, Yahoo and AOL have all thrown their hats in the ring as supporting this in their DNS setups, and in the future their SMTP servers will start filtering based on this."

The news follows a warning in June by analyst firm Garter Group that so-called phishing spam messages accounted for $2.4bn of fraud in the US last year.

Some IT managers have voiced concerns about the additional processing overhead of using SPF. However, one system administrator who tested the protocol extension said, "[A colleague's] mail server receives considerably more email than my own, and the DNS queries required for SPF do not seem to be having any impact on [his] mail delivery."

The ASSP update is testament to the responsiveness of the open-source development model. The idea was first mooted by an ASSP user on a web site on 21 July, and a stable beta version of ASSP implementing the protocol was ready some four weeks later. This is a clear example of how individual firms and users can influence the development direction of the open-source tools that they use.

Pier Fumagalli of the Apache Software Foundation, said, "This is one of the ways that open-source can win in the commercial market, although these benefits come not so much because ASSP is an open-source project as from it using an open development model."

He explained open-source projects are not necessarily open developments - in some cases they are driven by a relatively small community of developers focussed on a particular topic and reluctant to incorporate new ideas from outside. However, open developments by their nature tend to include open-source software.

For the latest news for IT professionals, visit ITWeek.co.uk