Microsoft's war on spam will be pushed up a notch with the coming of its Sender ID framework for email authentication, the company claims. Sender ID, an authentication protocol, works by verifying the domain name from which email is sent by checking the IP address of the server that sent the message against a published list of legitimate IP addresses. It was created through industry collaboration and its main advocate is Microsoft.

"Companies of all sizes are realizing the significant business value of email authentication and reputation services to improve email deliverability and help protect their brand identities," said Craig Spiezle, director of the Technology Care and Safety Group at Microsoft.