Spring Security - Add TAN system

I'm using Spring Security 3.04 to authenticate the users of my system using 3 Roles, while all of them are allowed to access something like a landing page.

From this landing page, there should be another system which can only be accessed by one Role and by a TAN-authenticated user.

So my question is: What would be the best way to add a third login-attribute to spring security? Or is there a way to store attributes within the securit开发者_运维问答y context? Or is there any other way to add a multi-level-authentication to my application using spring security?

Thanks in advance for any help!

Best regards, Robert

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There is an excellent walkthrough on how to integrate an external authentication mechanism here:

http://blog.springsource.com/2010/08/02/spring-security-in-google-app-engine/

That should get you on the right track.

Grant