How to create a Shared Login Service across Multiple Domains?

Question

I\'m interested in how to implement a shared cross-domain login system as well as best practices and security precautions to take. If you are familiar with 37Signals, you ar

Answer 1

Take a look at Jasig CAS http://www.jasig.org/cas . I think it will do what you want. It's open source, and has a number of plugins to allow you to authenticate use multiple sources of authentication and from multiple domains/languages.