We have not found a way to integrated AD with JSD, to automatically add and sync all users of a specific security group.
Our understanding, from reading the documentation and from testing the service desk, is that currently customers have to "sign up", e.g. to create a new user, not integrated with AD and with a different password.
We would like to be able to use a specific AD security group, even Domain Users, to add automatically users to the JSD customers group, and to let these users to use their AD credentials to login to JSD.
If you are using JIRA Server, then it's possible and please refer to JSD-4333.