Single sign on 10 different web sites
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I have 10 websites with different PHP related platforms like in Drupal,Joomla,Wordpressand and Core PHP etc(Even includes sub domains also). I want to create one new website with Registration and login functionality in Core PHP or else any framework. I want to implement single sign on functionality through this latest web site. So that can any one let me know the process to finish this.Thanks,Thirupathi