Exchange 2019 the innovations

The 2019 version of Exchange Server can run on Windows Server 2016, Windows Server 2016, and Windows Server 2019. The Microsoft directory service Active Directory must be present in the network, since Exchange Server integrates intensively with it, among other things for user management.

Since the 2013 version, a new product maintenance model on the part of Microsoft has been in effect: Approximately once per quarter, a so-called Cumulative Update (CU) is released, which reflects the complete status of the product in terms of bug fixes and feature enhancements at that time and can thus be used not only for updates, but also for new installations. Some Cumulative Updates are released as a traditional service pack (e.g. 2013 CU4 as SP1). It should be noted that Microsoft only provides product support for the last two Cumulative Updates in each case. In practice, however, security updates are only offered for the last Cumulative Update and the last Service Pack.

Scope of functions

The initially simple e-mail system became a comprehensive groupware solution. In version 2003, server-side filtering was implemented for the first time with the Intelligent Message Filter (IMF), which makes it possible to filter out unwanted e-mails. Since the 2013 version, rudimentary anti-virus software has also been included.

The functionality includes:

  •     Emails
  •     Appointments/Calendar
  •     Tasks
  •     Contacts/addresses
  •     Notes
  •     Mobile e-mail access via ActiveSync technology
  •     E-mail retrieval via POP3/IMAP4, e-mail delivery via SMTP
  •     Global address book
  •     Certificate-based authentication
  •     Support for Secure/Multipurpose Internet Mail Extensions (S/MIME)
  •     Intelligent anti-spam filtering: SmartScreen filtering technology, Intelligent Message Filter (IMF)
  •     Global accept and deny list (white list/black list)
  •     Anti-virus filtering or anti-virus API that can be used to connect third-party anti-virus software
  •     Support for Sender ID email authentication protocol
  •     Outlook Web App, web access to the server's functions
  •     Mixed operation with an Office 365 Exchange online service
  •     Data loss prevention

Basically, data is divided into personal and user-dependent data on the one hand and shared data such as the so-called public folders on the other hand, which enables group work.

Microsoft Outlook is usually used as the front-end application. As an alternative under Linux, Novell Evolution can also be used. However, it is also possible to use Exchange Server via a web application using Outlook Web App or via mobile devices using ActiveSync or telephone (Outlook Voice Access).

When using Outlook together with Exchange Server, the functionality of Outlook is extended. For example, an out-of-office assistant is offered that replies to incoming e-mails with an out-of-office message. Also certain other rules for incoming mails are processed directly on the server, even if the user has not started Outlook. The user can share folders of his mailbox, e.g. the calendar, with other users. When scheduling a meeting, the inviter is shown whether the invitee is available or already has another appointment.

Exchange Server can work with Microsoft SharePoint Server portal software and Microsoft Lync instant messaging product.

Exchange Server is managed through a Web application, Exchange Administration Center (EAC), or for advanced capabilities, through Exchange Management Shell (EMS) via PowerShell.

Clustering und hohe VerfĂĽgbarkeit

Exchange Server Enterprise Edition unterstützt Clustering von bis zu 4 Knoten bei Verwendung von Windows 2000 Server und bis zu 8 Knoten mit Windows Server 2003. Mit Exchange Server 2003 wurde auch das Aktiv-Aktiv-Clustering eingeführt, allerdings nur für Cluster mit zwei Knoten. In diesem Setup dürfen beide Server im Cluster gleichzeitig aktiv sein. Dies steht im Gegensatz zum häufigeren Aktiv-Passiv-Modus von Exchange, bei dem die Failover-Server in einem beliebigen Clusterknoten überhaupt nicht verwendet werden können, während ihre entsprechenden Home-Server aktiv sind. Sie müssen inaktiv darauf warten, dass die Home-Server im Knoten ausfallen. Nachfolgende Performance-Probleme mit dem aktiv-aktiven Modus haben Microsoft dazu veranlasst, zu empfehlen, dass dieser Modus nicht mehr verwendet werden sollte. In der Tat wurde die Unterstützung für Clustering im aktiven Modus mit Exchange Server 2007 eingestellt.

Das Clustering von Exchange (Aktiv-Aktiv- oder Aktiv-Passiv-Modus) wurde kritisiert, weil die Server in den Clusterknoten dieselben Daten nutzen müssen. Das Clustering in Exchange Server bietet Redundanz für Exchange Server als Anwendung, aber nicht für die Exchange-Daten. In diesem Szenario können die Daten als Single Point of Failure betrachtet werden, obwohl Microsoft diesen Aufbau als "Shared Nothing"-Modell beschreibt. Diese Lücke wurde jedoch von ISVs und Speicherherstellern durch "Site Resilience"-Lösungen wie Geo-Clustering und asynchrone Datenreplikation gefüllt. Exchange Server 2007 führt eine neue Cluster-Terminologie und -Konfigurationen ein, die die Unzulänglichkeiten des bisherigen "Shared-Data-Modells" beheben.

Seit Exchange Server 2007 bietet integrierte Unterstützung für asynchrone Replikation nach dem Vorbild des "Protokollversands" von SQL Server in CCR-Clustern (Cluster Continuous Replication), die auf MSCS-MNS-Clustern (Microsoft Cluster Service-Majority Node Set) aufbauen, die keinen gemeinsamen Speicher benötigen. Diese Art von Clustern kann kostengünstig sein und in einem, oder "gestreckt" über zwei Rechenzentren zum Schutz vor standortweiten Ausfällen wie Naturkatastrophen eingesetzt werden. Die Einschränkung von CCR-Clustern besteht darin, dass sie nur zwei Knoten haben können und der dritte Knoten als "Wählerknoten" oder Dateifreigabezeuge bekannt ist, der "Split Brain"-Szenarien verhindert und im Allgemeinen als Dateifreigabe auf einem Hub-Transport-Server gehostet wird. Der zweite Clustertyp ist das traditionelle Clustering, das in früheren Versionen verfügbar war und jetzt als SCC (Single Copy Cluster) bezeichnet wird. In Exchange Server 2007 wurde die Bereitstellung sowohl von CCR- als auch SCC-Clustern vereinfacht und verbessert; der gesamte Cluster-Installationsprozess findet während der Exchange Server-Installation statt. LCR oder Local Continuous Replication wird auch als "Cluster des armen Mannes" bezeichnet. Es wurde entwickelt, um eine Datenreplikation auf ein alternatives Laufwerk zu ermöglichen, das an dasselbe System angeschlossen ist, und soll Schutz vor lokalen Speicherausfällen bieten. Es schützt nicht vor dem Fall, dass der Server selbst ausfällt.




Exchange functionality in the 2019 version is divided into two so-called roles, which are defined during installation:

    Mailbox - contains the main functionality, holds the databases and receives the client requests
    Edge transport - additional protection of e-mail transmission between internal network and Internet (e.g. spam filtering); usually located in a DMZ

Client-server communication

Microsoft Exchange Server uses a proprietary interface called MAPI to communicate with the client, whose calls are transported using the RPC and HTTP protocols, and which is used by Microsoft Outlook for Windows, among others. When using current versions of Exchange Server and Outlook, the RPC layer is disabled in favor of greater flexibility, and MAPI is transmitted directly via HTTP.

Outlook for Macintosh, on the other hand, uses the newer EWS server interface. In the future, third-party vendors should also use this instead of the MAPI interface.











2000 (6.0)


2003 (6.5)


2007 (8.x)


2010 (14.x)


2013 (15.0)


2016 (15.1)




Originally, Microsoft offered the mail system MS Mail (up to and including version 3.5), but this could no longer meet the requirements of larger environments. It was only possible to create a maximum of 500 mailboxes on one server, and the storage of data in a file tree turned out to be more and more of a problem due to the amount of data to be managed as the volume of mail increased. Exchange itself was developed from scratch. In order to suggest a proximity to Microsoft Mail and to encourage customers to switch to Exchange, the version number 4.0 was used for the first Exchange Server. From the very beginning, secure data processing (relational database with 2-phase commit transactions) and scalability played a special role in the development. The basis has been the Jet Engine (Jet Blue) since the beginning, which was later also used for products such as Active Directory or the Kerberos Distribution Server.


Like Windows Server products, Exchange Server requires client access licenses, which are different from Windows CALs. Corporate license agreements, such as the Enterprise Agreement, or EA, include Exchange Server CALs. It also comes as part of the Core CAL. Just like Windows Server and other server products from Microsoft, there is the choice to use User CALs or Device CALs. Device CALs are assigned to devices (workstation, laptop or PDA), which may be used by one or more users. User CALs, are assigned to users, allowing them to access Exchange from any device. User and Device CALs have the same price, however, they cannot be used interchangeably.

For service providers looking to host Microsoft Exchange, there is a Service Provider License Agreement (SPLA) available whereby Microsoft receives a monthly service fee instead of traditional CALs. Two types of Exchange CAL are available: Exchange CAL Standard and Exchange CAL Enterprise. The Enterprise CAL is an add-on license to the Standard CAL.