Access Restrictions on Dashboard

Hi All,

I want to implement access restrictions on my xcelsius dashboards or data security.Like a particular user should be able to see only the data related to his department.We are on SAP BO XI 3.1 and i am using QaaWS to supply data to my dashboards which are finally getting data from BEx queries.

Just wanted to know possible methods through which i can achieve this apart from using single sign on method.

Any help will be highly appreciated.

Thanks...