Azure Active Directory Fundamentals

When first hearing the name “Azure Active Directory,” or Azure AD as it is commonly referred to, you could be forgiven for assuming this was just an Azure-hosted instance of the Active Directory Domain Services that you know and use on premises. However, you would be wrong. While on-premises AD is focused on a hierarchical structure based on X.500, offering interaction via LDAP and authentication using primarily Kerberos, that is not at all what Azure AD is nor would we want it to be. Remember, AD works great on premises, where all the machines are part of my organizational island, with secrets shared and unlimited ports available for communication. When dealing with the cloud, however, that is not the case. We are communicating across the Internet, which means communication will mostly be limited to HTTPS (port 443). We are also potentially dealing with thousands of systems, where secrets may not be possible. The goal is for an identity...