If possible:

1. Gather the needed domain controller LDAP connection information for a particular user from the global catalog.
2. Connect to the specific domain controller to update user attributes.

This is useful if:

• You have multiple domains in a forest, and are pointing Crowd at the GC to authenticate users.
• You wish to modify details of the users. Since the GC is read-only, you can't just make modifyAttribute calls to it.