Online Authentication Techniques

What online authentication services are available.

I know about

• Live ID
• OpenID

Are there any other major playe开发者_如何学运维rs.

I am particularity interested in authentication federation so that we can log in once and use on multiple sites (if this is even possible).

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There is also Facebook Connect, to add to your list.

However, you are conflating two concepts: single sign-on (SSO) and single password. OpenID provides a distributed single-password system, where users log in to their ID provider once for each consumer site they visit. Windows Live ID provides a centralized single-password system, where users log in to Microsoft once for each consumer site.

On the other hand, you say "we can log in once and use on multiple sites". That is SSO. An SSO system like Kerberos has the user log in once, and then use the credentials they obtained across multiple authentication realms. Using federated-trust systems like Cosign or Shibboleth, it's possible to trust credentials from other institutions.

If you clarify exactly what you're trying to do, you will probably get a better answer. But there's more to it than you seem to have gotten a handle on.