CallVerifID Adds Another Authentication Layer to OpenID
 

OpenID is an service which allows users to log on to many different web sites using a single username / password. This eliminates the need to create and remember a strong (http://en.wikipedia.org/wiki/Password_strength) username / password for each site. The assumption, of course, is you create a strong OpenID.

Of course, if that information is lost or stolen, you're in big trouble. JanRain (http://janrain.com/about/) is "a recognized leader and primary catalyst driving the OpenID market forward," and they've created a second authentication layer for OpenID, using a callback service.
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*Source: Tech-Ex (http://technologyexpert.blogspot.com...ticaion.html)*

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