our initial reaction). Barring a bid from another suitor, such as News Corp. (not likely), eBay (even less likely), Google (no way), or a private equity firm, or a partnership with Google, most analysts seem to agree that Microsoft's bid will be accepted by Yahoo! One of the biggest hurdles in merging two massive Internet properties like these, though, is merging their gigantic and proprietary user authentication systems. There is, however, something that could save Yahoo! and Microsoft engineers from a massive headache in that regard: OpenID.The takeover of Yahoo! by Microsoft is almost a foregone conclusion (see
Yahoo! has some experience in merging identity systems. It has switched Flickr users over to its unified Yahoo! ID system, for example. But merging the hundreds of millions of accounts across the Yahoo! and Microsoft web ecosystems will make the Flickr job seem like child's play.
OpenID, though, could make merging the two systems a relative snap. OpenID is a decentralized identity management system that lets users log into multiple sites using a single set of sign on credentials. The idea is that if everyone supported OpenID, you'd only have to remember one username and password for all your various accounts. Emre Sokullu wrote a great overview of the system last year.
Both companies have dabbled in OpenID support. Last February Bill Gates told a group at the RSA conference that Microsoft would collaborate with JanRain, Sxip, and VeriSign on interoperability between OpenID and Windows CardSpace. Earlier this month Yahoo! gave OpenID its biggest bump by becoming an OpenID provider.
But while Yahoo! is letting its roughly 250 million users make their accounts OpenID compatible, and thus log into other sites using their Yahoo! ID, they're not authenticating OpenIDs from outside providers. That would be necessary in order to use OpenID to merge the sign on systems of Microsoft and Yahoo!
If Micosoft became an OpenID provider via its Live ID system, as Yahoo! has done, and both companies authenticated outside OpenID account on their systems, then users could log into any Microsoft or Yahoo! service with the ID they already have. All that would be left would be a utility to let people link two accounts (i.e., tell OpenID that when I log into Hotmail with the Yahoo! ID I use for Flickr I want to see the Hotmail account I've had for 10 years). As far as I know, this isn't very difficult and is something both companies have experience with from past acquisitions.
Full support of OpenID by both Microsoft and Yahoo! would be a huge win for OpenID, as well. When Yahoo! announced support of OpenID a couple of weeks ago, TechCrunch reported that there were 120 million active OpenID accounts. Adding Yahoo!'s 250 million accounts triples that number. I'm not sure how many accounts are in the Live ID system, but with over 260 million Hotmail users and over 240 million Windows Live Messenger users, you can bet that it's a lot.
So how likely is it that Microhoo adopts OpenID? My best guess is: pretty likely.
.NET Windows Passport Live ID is a confusing system for users that changes names every three seconds, while OpenID is quickly becoming the Web 2.0 standard. Further, chief competitor Google also recently became an OpenID provider via Blogger.