OpenID, how open is it?

Question

Maybe I'm confusing the issue. I understand, using OpenID, people can log into my site using either Yahoo / Google / Other providers without signing up a username/password on my site. Great.

The issue for me though is how do I query Yahoo network information of a user when the user signed into my site using Google OpenID? I mean I don't see a connection between Google and Yahoo. It sort of defeats the purpose of OpenID, no? (As both Google and Yahoo are OpenID providers and yet, they can't talk to each other for the same user. Then, what good does it do to have a "universal log in"?)

I actually see FlickR, you can (part of Yahoo Network), you can sign in using Google ID, but the issue is, I already have a Yahoo ID, how do you connect my Google OpenID with my existing Yahoo ID?

My idea of a "Universal Login" is that it doesn't matter which provider I registered my account with, this login can be used on any OpenID provider. If I have an existing account, I can hook it up or replace with this exiting ID. From then on and forward, I can get my information anywhere as long as I login using this "Universal Login"

A bit confused. Hope someone can clarify the issue for me.

Thanks

Answer 1

OpenID is an open specification. It define an interface between a provider and a consumer that is identical[1] between all providers and all consumers.

It's not about connecting your Yahoo identity with your Google identity, it's about letting you to identify yourself by any[2] of your OpenID identities (Yahoo, Google, etc as provider) on many other websites (as consumer) instead of creating new user-accounts and remembering many passwords.

Yahoo and Google are both provider (not consumers).

[1] Almost identical, because they may support additional extensions.

[2] Or optionally some.