To ensure a high quality experience to your users, it is important that you consider the following before implementing User Management in your environment:
What is the number of users who log into ZCM concurrently during peak load? This will help you understand what the overall load on the directory servers will be during peak times.
How often are assignments modified for users in the zone?
How often are users moved to different groups, and how often are modifications done?
What is the network infrastructure like, and which branches or geographic sites will your users be logging on from? How many at each?
Are the users members of several groups or nested groups?
How are the assignments made to groups or users in the organization? This is important because if the majority of end users fall into similar categories, a group-based assignment is highly recommended. However, if the end users are fairly segregated in multiple groups and the policies are widespread, then the design choices might differ significantly.
What authentication mechanisms do you want to support? ZENworks supports simple user name and password authentication, Kerberos authentication (AD only), and Shared Secret (eDirectory only) methods.