PKI authentication using a Smart card for SSO in Portal and ECC

Dear Exprt,

We wanted to do an SSO with the user's smart card to logon to SAP Portal and ECC. The below document from SAP says its possible but i wanted to know the steps to implement it.

Client Certificate Logon for SAP GUI - User Authentication and Single Sign-On - SAP Library

Can some please help me..?

Thanks and Regards,

M.D.Sahu