With each release of Windows Server, Microsoft transforms and updates its network operating system (NOS)—Active Directory Domain Services—into one of the most comprehensive network-infrastructure engines in the industry. Each time, organizations are faced with a key question: is our existing Active Directory able to respond to the growth and changes the organization needs to go through with an update to the NOS? According to Microsoft, the answer is no for up to 80 percent of their customer base. For these customers, this means creating a new directory structure and migrating all data into it.