OpenID is really interesting. I will not explain in details what it is about because openid.net or wikipedia will probably do that better than me. Basically, it's a try to get an unique way to log on various websites. For example, with OpenID, you can get authenticated on Facebook with your Google account[1]. Actually, OpenID is much more than a standard way to log on, it lets you externalizing the authentication server. That means you can use the OpenID account linked to your Yahoo! account[2] or even the one linked to your wordpress blog or any any one you may already have[3]. That also means you can use your own !

Why should you use your own server to provide your own identity on Internet ? Actually, this question should be "Why should I trust someone else to provide my identity on Internet ?". Indeed, with OpenID, you can externalize the authentication but that also means centralizing it. Having a lot of identities on Internet is annoying : you must file the same information, you have a lot of passwords, you don't always remember your username... But having the same account to log everywhere makes you very dependent on this account. If your OpenID provider closes its service, ask you to pay for it, doesn't respect your privacy, or anything else, you will be in a bad situation.

To prevent this situation, the best solution is to run and use your own OpenID server. If you already have one for anything else, adding OpenID is going to be easy. There is even a page with some solutions. phpMyID is really appreciated because it's lean but it's designed to provide only one account. That means you will not be able to offer an OpenID server to your friends. That's why I prefer SimpleID. How to setup the server will be maybe for another entry but I suppose anyone interested to do that will know how to found the information[4].

The simplest way is to delegate your authentication. That means you can use an OpenID account from myOpenID or any OpenID provider and, in your blog or any web page you control, you can add these lines in the HTML HEAD section:

<link rel="openid.server" href="http://www.myopenid.com/server" />
<link rel="openid.delegate" href="http://username.myopenid.com/" />

The example is using myOpenID but it could be wordpress, Yahoo! or anything else. openid.server is the server you want to use. openid.delegate is the OpenID account your provider told you to use (like username.wordpress.com for wordpress).
This solution lets you use your blog URL (or any webpage you want) as an OpenID account and it will transparently use the specified server. That means you will be able to change the server when you want without breaking your OpenID account. So, you are not as much dependent from the provider as you were. Unfortunately, there will always be a third party which you have to trust while you are using someone else as a provider.

Maybe you should now ask one of your geeky friend if she/he didn't setup an OpenID server or do it yourself ?

Notes

[1] http://developers.facebook.com/news...

[2] http://openid.yahoo.com/

[3] look at http://openid.net/get-an-openid/

[4] some hints: http://www.intertwingly.net/blog/20...