Microsoft Server & Exchange Solution
Windows Server is a brand name for a group of server operating systems released by Microsoft. It includes all Windows operating systems branded “Windows Server”, but not any other Microsoft product. The first Windows server edition to be released under that brand was Windows Server 2003. However, the first server edition of Windows was Windows NT 3.1 Advanced Server, followed by Windows NT 3.5 Server, Windows NT 4.0 Server, and Windows 2000 Server; the latter was the first server edition to include Active Directory, DNS Server, DHCP Server, Group Policy, as well as many other popular features used today.
This brand includes the following operating systems:
Microsoft has also produced Windows Server Essentials (formerly Windows Small Business Server) and the discontinued Windows Essential Business Server, software bundles which include a somewhat restricted Windows Server operating system and some other Microsoft Server products.
Microsoft Exchange Server
Microsoft Exchange Server is a mail server and calendaring server developed by Microsoft. It runs exclusively on Windows Server operating systems.
Exchange Server was initially Microsoft’s internal mail server. The first version of Exchange Server to be published outside Microsoft was Exchange Server 4.0. Exchange initially used the X.400 directory service but switched to Active Directory later. Versions 4.0 and 5.0 came bundled with an email client called Microsoft Exchange Client. It was discontinued in favor of Microsoft Outlook.
Exchange Server uses a proprietary protocol called MAPI. Over time, however, it added support for POP3, IMAP, SMTP, and EAS.
Exchange Server is licensed both in the forms of on-premises software and software as a service. In the on-premises form, customer purchase client access licenses (CALs). In the software as a service form, Microsoft receives a monthly service fee instead (see Microsoft Office 365).