Do you mean the user management? I'm not a SAP server Admin, so I hope I can reply your questions properly.
We have no Active Directory / LDAP-Integration of our SAP systems. The user id's for the access of the published Application are quite different from the SAP logins. We're hosting many SAP backend systems for several customers. A customer usually have about 4-6 SAP systems as entry points.
Our plan is to publish them a common frontend. Therefore we want to provide them a full list of every existing system. This will be a long list. Due the ease of usage the users should have the possibilty to create favorites or shortcuts within the published application.