Hello Abu,
I would like just to clarify for you the following:
As part of the SAP Single Sign-On product you get:
1) Secure Login Server for issuing X.509 Client Certificates
2) SAML Identity Provider for issuing SAML assertions.
Both solutions are deployed and running on SAP NW AS JAVA.
Secure Login Server could be configured to accept SAML assertions for authentication but you do not need the Secure Login Server when you implement Mobile SSO based on TOTP (see the guide provided by me above).
In order to implement Mobile SSO solution based on TOTP, you need to implement our SAML Identity Provider and to configure the trust between the SAML IDP and your AS ABAP system as SAML SP (this all is described in the guide, provided by me above).
If you have any further questions just let me know.
Regards,
Donka