Yes, then also we can achieve SSO between BO and EP. With the Ref of 2nd point Below, we need to have SAP Alias to all the Enterprise users to have SSP between BO and EP.
SSO can be configured in two ways to access the reports from SAP netviewer portal.
- Win AD + SSO= Please follow the document to configure the same
http://blog.jamiebaldanza.org/wp-content/uploads/2012/04/Crystal-2011-AD-Authentication.pdf.
2. SAP SSO= Please follow the document to configure the same
http://wiki.sdn.sap.com/wiki/display/BOBJ/BI4+Integration+into+the+SAP+Entreprise+Portal+7.0.x
Hope this answers your question.