Sender ID loses open source support

Opposition to Microsoft's Sender ID anti-spam email scheme is growing in the open source community, which is complaining about the software giant's licensing terms.

The Apache Software Foundation (ASF) backed away from supporting Sender ID last Thursday, and fellow open source developer Debian followed suit at the weekend.

Sender ID aims to verify that an email has been originated within the internet domain from which it claims to come. The idea is to stop spam with forged sender email addresses getting through.

The ASF said in a statement: "The current Microsoft royalty-free Sender ID patent licence agreement terms are a barrier to any ASF project which wants to implement Sender ID.

"We believe that the current licence is generally incompatible with open source, contrary to the practice of open internet, and specifically incompatible with the Apache Licence 2.0.

"Therefore, we will not implement or deploy Sender ID under the current licence terms."

Debian also maintains that Microsoft's licence terms are incompatible with its own free software guidelines, and will not implement or deploy Sender ID.

"We believe that the current licence and resulting encumbrances are incompatible with the Debian Free Software Guidelines, unlike other internet standards that Debian is able to support," the company said in a statement.

"Therefore, we cannot implement or deploy Sender ID under the current licence terms.

"Indeed, we would be forced to remove Sender ID support from software we ship that does support Sender ID upstream according to the terms of our social contract."

Debian claimed that its concerns mirror those of the ASF, the Free Software Foundation and the Postfix, Exim and Courier maintainers.

The ASF stated that it had raised these concerns with the Internet Engineering Task Force, which is working on ratification of the standard, but that they had not been addressed.

But Microsoft has hit back with its own statement. "AOL, Cloudmark, IronPort, VeriSign, Bell Canada, and the 54-member Email Service Provider Coalition have voiced support for the Sender ID licence offered by Microsoft," it said.

"There is broad support for Sender ID technology and we encourage others to support and implement this technology so that together we can do more to tackle spam."