Yahoo and Cisco Systems are collaborating on an authentication technology to reduce e-mail forgery, the companies said on Wednesday. The specification, called DomainKeys Identified Mail, or DKIM, relies on public key cryptography. The system attaches a digital signature to outgoing e-mail so that recipients can verify that the message comes from its claimed source. The technology merges Yahoo's antispam proposal called DomainKeys with Cisco's Internet Identified Mail system--and the specification will be offered royalty-free to the industry, according to the compannies.
AOL and Microsoft have said they're looking at DomainKeys, but the providers are pushing their own e-mail authentication technologies. AOL's SPF and Microsoft's Sender ID check an e-mail's identity through its Internet Protocol address, and can be used alongside DomainKeys.