Xauth defined Extended Authentication, an open platform for extending authenticated user services across the web.
EXTENDED AUTHENTICATION A proposed Web standard that detects which social networks the website visitor is already logged into
BENEFIT Enables the site to offer only the website visitor’s preferred sites as options for sharing instead of a long list of every possible sharing site
BENEFIT Facilitates including second-tier sharing services (such as Google Buzz) with greater ease Speeds page load time
HOW IT WORKS Participating services generate a browser token for each of their users. The XAuth Token can be anything, so services have the flexibility to define whatever level of access they choose
HOW IT WORKS Publishers can then recognize when site visitors are logged in to those online services and present them with meaningful, relevant options. Users can choose to authenticate directly from the publisher site and use the service to share, interact with friends, or participate in the site's community.
IMPLEMENTATION Meebo is putting XAuth into its Meebo bar, which appears on a number of publisher websites
Xauth SUPPORTERS Google, Microsoft, Yahoo MySpace, Disqus and Meebo’s publishing partners including Time Inc. and MTV Networks
What about OAuth? Oauth is an open protocol to allow secure API authorization in a simple and standard method from desktop and web applications.
OAuth OAuth allows the User to grant access to their private resources on one site (called the Service Provider), to another site (called the Consumer, not to be confused with you, the User).
What about OpenID? While OpenID is all about using a single identity to sign into many sites, OAuth is about giving access to your stuff without sharing your identity at all (or its secret parts).
OAuth OAuth attempts to provide a standard way for developers to offer their services via an API without forcing their users to expose their passwords
Industry Protocols Google AuthSub AOL OpenAuth Yahoo BBAuth Upcoming API Flickr API Amazon Web Services API
Xauth vs. OAuth XAuth tells you where to ask for OAuth from
Xauth and OAuth Example: XAuth tells a webpage "this is where the site visitor does social networking."
Xauth and OAuth Then, OAuth is the way the user logs in there, granting the site permission to access their info without seeing their password