There are two websites in different domains, in different server, with different databases, developed in different platforms, both for banking purposes. In the first website (I'll call it "A") the user (bank operator) will login with his credentials.
The problem is: They need to put a "link" to the B-site into the A-site, and the user logged in A should become logged-in also in B. Of course, I need a strong-secured system for this "cross site authentication" based on username.
The certificates system could not be done because we should install certificates in each client pc, and it's impossible to manage.
Any ideas?