As explained, the hybrid cloud is a reality for most organizations, whether it's because of regulations or investment in local infrastructure. We already covered how to migrate or extend services to the cloud, and a very important part of this is managing identities in the cloud. Data is important, but managing who can access that data is just as important. In extending local infrastructure to the cloud, we can set up a replica of the domain controller and use the Active Directory to manage identities and delegate access, but this only extends to IaaS. 

To manage this with PaaS, we must use Azure Active Directory, which is often called Identity as a Service. In the next chapter, we'll discuss Azure Active Directory, how to use it, and even extend local identities to Azure Active Directory.