The specification, once it becomes mainstream, would provide a much needed feature for the SMTP protocol: A way to ensure that mail addresses are not spoofed, and an e-mail actually is received from the server responsible for it.
The reworked proposed standard, unlike the previous one will not be patented by Microsoft which will renew support from open source groups and AOL.
The standard incorporates Microsoft's Purported Responsible Address (PRA), also known as Caller ID, and Sender Policy Framework (SPF), developed by Meng Wen Wong of Pobox.com. It also provides backward compatibility for those who already implemented these standards in their original form.
We are also covering SPF developments, check out our recent articles for more information about this important subject:
Some information about the Microsoft standard is provided here:
http://www.microsoft.com/mscorp/twc/privacy/spam_senderid.mspx
