How to Sign In to Facebook Using Google

So you have a
Facebook
>
account, right? And you use
Google Mail
>, right? Good, then this is for you. It’s just recently become possible for
you to sign into Facebook automagically, i.e. without entering your Facebook
username and password, just because you’re already signed into GMail. It’s
full of win.

OpenID
>

1. Convenience: faster registration on new sites: get setup in
   seconds

2. Simplicity: a single username and password to remember

3. Security: you don’t give websites your password

If you’re interested in more details, I just finished a piece on web auth
technologies
here
>, but the point is that OpenID is blowing up. Everyone’s getting into it:
Google, Yahoo, Facebook, Verisign…everyone. The big players who
aren’t there now will be soon.

Facebook + Google = OpenID

Well, Google is now the behemoth of Identity Providers, and Facebook is now
the Grand Pubah of OpenID Relying Parties. It’s a phenomenal combination for
users. In other words, Facebook is saying to the world:

Setup

So here’s how to get going–in like two minutes. First, sign into Facebook
normally–using your Facebook username and password–and go to your Settings.
On the default, left-most tab you’ll have a section called “Linked
Accounts”. Click “Change” there to add an account.

Select “Google” from the pull down menu and you’ll be asked to allow
Facebook and Google to interact. Once you’ve authorized the connection your
two accounts are linked! Now sign out of Facebook (but stay logged in to
your Google account) and then go to the Facebook homepage.
You’ll see some trickery taking place in the URL bar, and then you’ll be
logged into Facebook without having to enter anything!

The way this works is just like when you enter an OpenID identity manually
on a site: you’re getting transparently redirected to the OpenID provider
(Google, in this case) where Facebook confirms that you’re already logged in
and subsequently lets you into the site.The only difference is, instead of
you providing an OpenID through a login form, Facebook already knows where
to redirect you based on the previous “Linked Accounts” step.

Notice that you can also add a number of other account links as well,
including various OpenID providers, and Yahoo! My favorite, however, is
Verisign PIP, because it allows me to use
two-factor authentication
>
to access my OpenID provider.

Anyway, enjoy your new transparent login to Facebook through Google, and
keep your eye out for more OpenID developments around the web. ::