[Tutorials] [General RDS Information] – Published Jan 2012

A Windows Server in Remote Desktop Session Host role allows simple centralization of user applications and the use of low-maintenance clients.  In the past the technical term for this arrangement was server-based computing.  In these days it became more common to call it presentation virtualization, allowing cost-effective and highly efficient application centralization and consolidation scenarios.  However, today’s modern remote desktop server environments go far beyond the rather simple concepts behind server-based computing.

There are a couple of things you should know about Remote Desktop Services before getting started.

The Different Remote Desktop Services Modes

In Windows Server 2008 R2, remote desktop functionalities are available in three varieties; in RD Session Host role, in RD Virtualization Host role and in remote administration mode.

Remote Desktop Session Host Role

A Windows Server with the Remote Desktop Session Host role activated is commonly referred to as remote desktop server, even if this is not an official product name.  Such an RD server is an efficient and reliable way to deliver Windows-based applications over the network.  The RD server represents a central installation point for applications that can be accessed simultaneously by several users from their respective local workstations.

NOTE: A multiple-user environment has special configuration requirements regarding the applications installed.  If applications are already installed on the Windows Server operating system and the RD Session Host role is activated later, some of the applications may not work properly.  This is why applications intended for simultaneous access by multiple users must be installed after the RD Session Host role was activated.

Remote Desktop Virtualization Host Role

A Windows Server with Remote Desktop Virtualization Host and Hyper-V roles activated is the ideal platform to host virtual machines used to provide virtual desktops.  A personal virtual desktop can be assigned to a user account in Active Directory Domain Services.  A virtual desktop pool provides virtual desktops that are not pre-assigned to a user.  Such a setup requires multiple identically configured virtual machines.  A virtual desktop in a pool can be configured to roll back to a previous state when a user logs off from the computer.

The RD Virtualization Host role is an interesting option for organizations that are planning to implement a Virtual Desktop Infrastructure.  The goal is to provide personal virtual desktops or virtual desktop pools to users within their organization.

Remote Administration Mode

The remote administration mode of Windows Server was first introduced with Windows 2000 Terminal Services.  Under Windows Server 2003, this mode was renamed remote desktop due to its relation to Windows XP.  It was developed mainly to allow remote access to a server running on Windows 2000, Windows Server 2003 or Windows Server 2008.  This enables users belonging to the group of administrators to remotely access their interactive Windows Server desktops across the network, including all their administrative tools for installed server applications or services.

Performance or server application compatibility of a Windows Server should not be compromised by remote administration.  Therefore, remote administration mode only requires a minimum of additional memory and processor resources.  A maximum of only two remote administrator sessions and one local console session are allowed per Windows Server.  The remote administrator sessions do not require special licenses.

NOTE: Consoles are referred to as input and output devices physically connected to the server hardware.

With past versions of Windows Server some programs require a direct logon to the console for administrative tasks.  Under Windows 2000, it was not possible to use the console remotely through Terminal Services.  Windows Server 2003 introduced system extensions that allowed you to run a console remotely by using the /console parameter in the Terminal Services client software.  Starting with Windows Server 2008, the concept of the console session was substantially modified, eliminating the necessity to use a dedicated remote console session for administrative tasks.

Application Access

A remote desktop server allows access to one or multiple remote applications.  This sounds rather obvious.  However, there are different ways how a user may launch remote applications, each way including specific user interface and usability characteristics.

Programs on the Desktop

If a user wants to display a remote desktop on the client, he or she selects the IP address or the logical name of the corresponding server.  According to the permission settings, the appropriately authorized user can launch and use the installed applications on that desktop.  This access concept can also be used on simple clients that have no desktop or on client desktops with reduced functionalities, such as a Windows Embedded desktop.

If all of a user’s required applications are not installed on the same remote desktop server, that user may then create remote desktops for each required application that exists on a different terminal server. For most users, the effect of accessing applications through multiple concurrent desktops is confusing which often leads to increased support costs.

Automatic Program Start

When remote desktop servers are used, different configuration options allow the selection of an application that is started automatically when a user logs on.  After logon, the predefined application will consume the complete area of the server desktop that is displayed on the client.  Configuration of this option is available to either a user on the client side, an administrator who is responsible for the user accounts, or the remote desktop server administrator.

Even if the desktop is not directly visible when the automatic program start option is used, the desktop functionalities are still available, which becomes very obvious when the application is minimized to an icon.  But still this concept is very good for clients with limited local desktop functionalities.  However, the restrictions concerning access to desktop elements stay exactly the same as if the user would access the desktop directly.

RemoteApp

The scenario of Remote Applications Integrated Locally (RAIL) – officially referred to as RemoteApp – resolves the requirement that a remote desktop server’s desktop should not be displayed on the client when a remote application is started.  Pushing the icon of a remote desktop server hosted application to a client desktop is one of the core mechanisms required for launching remote applications.  It includes some additional configuration and requires the enhancement of the client’s window manager components providing presentation of desktop elements.  This allows the application published by a remote desktop server to be displayed in an individual window on the client desktop.

If one or more remote applications can be launched on the client without the surrounding of the server desktop they are executed inside seamless windows.  As a result, the application looks as if it was executed locally on the client.  Authentication is only needed when the user launches the first application in a seamless window.  Using seamless windows produces adequate results only if the client has its own fully functioning desktop including proper window management.

NOTE: Launching a seamless application on a client still requires the creation of a full user session and a dedicated desktop on the server, even if this desktop is not visible on the client.

[Tutorials] [General RDS Information]