Experts question Microsoft's Caller ID patents

Just a week after Microsoft Corp.'s Chairman and Chief Software Architect Bill Gates unveiled his company's plan for securing e-mail communications, leading e-mail authorities, legal experts and at least one Internet service provider (ISP) are expressing concerns about the e-mail sender authentication plan, known as Caller ID.

Some experts agreed that the technology is promising. However, Microsoft's claim that it owns patents around Caller ID and its decision to license the technology to third parties, rather than submit it to an Internet standards body, have riled e-mail experts and domain owners, some of whom said they worry about a power grab by the Redmond, Washington, company and are wary of signing on to the new system.

Caller ID allows Internet domain owners to publish the IP (Internet Protocol) address of their outgoing e-mail servers in an XML (Extensible Markup Language) format e-mail "policy" in the DNS (Domain Name System) record for their domain. E-mail servers can query the DNS record and match the source IP address of incoming e-mail messages to the address of the approved sending servers, Microsoft said. The goal is to reduce spam for end-users.

Speaking last week at the RSA Conference in San Francisco, Gates set out an ambitious agenda for deploying Caller ID, saying it would be "very easy for people to apply," and that Microsoft hoped to have Caller ID in place by the third quarter, provided it could reach "the right agreements" with ISPs and e-mail providers.

Gates did not elaborate on what those agreements might involve, but said that Microsoft had some patents related to "the fundamentals" of Caller ID which is "royalty free, available for everyone to use," according to a transcript of his RSA speech.

Microsoft published a technical specification for Caller ID on its Web site, along with an "implementation license" for organizations that want to develop and implement software conforming to the specification. (See: http://www.microsoft.com/mscorp/twc/privacy/spam_callerid.mspx)

At least one e-mail expert who has studied the agreement said it could be an obstacle to Caller ID's widespread adoption.

"Given the license they're offering, it's clearly a problem," said John Levine of the Internet Engineering Task Force's (IETF's) Anti Spam Research Group.

Like some others, Levine said he is concerned because Microsoft has not said what technology its patents cover. He also took issue with its assertion in the license agreement that Caller ID licenses cannot be transferred from one party to another, leaving the job of assigning licenses to Microsoft.

"The way the license is written, you can't read (Microsoft's) intentions," he said. "They could stop giving out (Caller ID) licenses at any time, or suddenly say that Caller ID is bundled with Windows."

Microsoft's agreement grants licensees a fully paid, royalty-free license to "make, use, sell, offer to sell, import, and otherwise distribute" licensed implementations of the company's Caller ID patents. The company will not seek royalty payments for use of the patents now or in the future, according to a statement by George Webb, business manager for Microsoft's Antispam Technology and Strategy Group.