OpenID

Think of all the sites you have registered with - blogs, emails, social networking sites, social bookmarking sites, photo sharing sites, video sharing sites, feeds.... With Web 2.0 hitting the internet in a big way, you find a new site you can't live without, springing up every other day. Now that means you will be having 100s of usernames and passwords to remember. Ever thought why we can't have single digital identity across the Internet?

OpenID is a single sign-on system, a way to use a single digital identity across the internet. Using OpenID-enabled sites, you do not need to remember authentication tokens such as username and password. Instead, you only need to be registered on a website with an OpenID "identity provider" (IdP). Since OpenID is decentralized, any website can employ OpenID software as a way for users to sign in. It eliminates the need for multiple user names across different web sites, simplifying your online experience.

An OpenID provider is a service provider offering the service of registering and providing OpenID authentication. You get to choose the OpenID Provider that best meets your needs. A URL or XRI is chosen by the End User as their OpenID identifier, which can be used to login to any site that accepts OpenID.

OpenID is still in the adoption phase and is becoming popular, with organizations like AOL, Microsoft, Sun, Novell, Yahoo etc. beginning to accept and provide OpenIDs.