Citrix Exam 1Y0-440 Topic 7 Question 18 Discussion

Scenario: A Citrix Architect has met with a team of Workspacelab members for a design discussion. They have captured the following requirements for NetScaler design project:

The authentication must be deployed for the users from the workspacelab.com and vendorlab.com domains.

The workspacelab users connecting from the internal (workspacelab) network should be authenticated using LDAP.

The workspacelab users connecting from the external network should be authenticated using LDAP and RADIUS.

The vendorlab users should be authenticated using Active Directory Federation Service.

The user credentials must NOT be shared between workspacelab and vendorlab.

Single Sign-on must be performed between StoreFront and NetScaler Gateway.

A domain drop down list must be provided if the used connects to the NetScaler gateway virtual server externally.

Which method must the architect utilize for user management between the two domains?