Yahoo and Cisco Team Up in the Fight Against Spam

Yahoo Inc. and Cisco Systems Inc. are teaming up in the battle against spam by combining their antispam technologies to create a new e-mail authentication system - the companies announced this week.

The new collaboration is called DomainKeys Identified Mail (DKIM) and will utilize Yahoo's DomainKeys authentication and Cisco's Internet Identified Mail technologies. The companies are releasing the technology to others in the industry, royalty free. They are trying to reduce the overall spam traffic that has been a plague for businesses and consumers.

Yahoo's contribution - DomainKeys - uses public-key cryptography to authenticate an e-mail sender at the domain level. When the message is sent, the sender generates a signature and includes it with the e-mail's header. When the receiving server accepts the e-mail it can verify the signature using a public key.

Cisco's authentication technology also uses cryptography. Instead of associating a signature with the sending server, Cisco's Internet Identified Mail associates it with the message itself. A receiving server would check the signature and determine if the message is authorized to for use by the sending address.

DKIM will incorporate aspects of both technologies to add extra layers of authentication. It is still unclear exactly how the new DKIM system will be incorporated into current systems. Yahoo is currently using their DomainKeys technology on Yahoo! Mail and is offering it to those in the industry. Cisco has also released the source for their Identified Internet Mail last year.

This partnership comes just a week after Microsoft announced their own set of antispam tools. Both AOL and Microsoft have stated that they were looking into Yahoo's DomainKeys, but they were also pushing for their own separate antispam solutions.