By now, you’ve probably heard about Xauth.org, the collaboration between Meebo and companies like Google, Yahoo, MySpace, etc. If not, it’s an open platform for extending authenticated user services across the web.
On the Google Code blog, Google’s Open Web advocate Chris Messina shares some details about how it works from a technical perspective. He shows a snippet of Meebo’s XAuth page, where a user sees various logos. “When this page loaded, it requests the list of services that have been registered with XAuth by making an HTML5 window.postMessage request to xauth.org,” he explains.
He goes on to explain what happens when a user clicks through to one of the linked demo pages, and when a user successfully authenticates. Take a look at Messina’s little rundown here.