to be precise, you need jboss-federation server installed *only once per web domain* which could consist of multiple partners. you need jboss-sso.sar (client plugin part) deployed with every partner that wants to join the federation regardless of domain Example: say two domains abc.com, and xyz.com, you need to deploy jboss-federation-server only once for each one If you have a single domain and multiple sites on that domain, you again need to deploy jboss-federation-server only once for this domain and not for each partner in the domain Thanks View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4158996#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...