Virtualised desktops: provisioning done the MS way
Two paths to IT happiness
A virtualised desktop offers huge advantages, both to the user and to the IT department.
For anyone using a laptop at home or on the move, the experience is the same and everything is exactly as when they left it.
What they see is the image of a desktop running in a virtual machine on a server in the data centre. Users log onto the server via their browsers and are offered a virtual desktop and other resources appropriate to their role. They have entered a secured virtual environment where they can start being productive.
From an IT perspective, a virtualised desktop offers easier, centralised management and a decoupling of the hardware from the operating system and application set.
This makes the desktop more secure and insulates the software, which avoids the perpetual race to upgrade hardware.
That is the promise, and essentially there are two ways of delivering it.
Suits you, sir
The first and most cost-effective way, also known as session virtualisation, is suited to very thin clients, users with fairly standard needs such as call centre employees, and places where the network link can be relied upon.
For this you need a server running Microsoft Windows Server 2008 R2 or later. This includes Remote Desktop Services (RDS), whose core job is to manage the process of connecting to a machine which has been configured by the IT admins.
Applications then run in that session as if they were on a physical device. The connection, including the screen image, is delivered by the Remote Desktop protocol, which allows multiple users to share the resources of the server.
If end-users need more than a handful of standard applications, the alternative is to use a form of virtual desktop infrastructure. This is suited to home and mobile workers who need access to the corporate desktop, and places where the network link may be intermittent.
A bit rich
The desktop – one per user – runs as a virtual machine on a host server in the data centre. The desktop experience is richer than with RDS and closer to what is offered by one running locally, while giving the IT department the benefits of more control and centralised management. Additionally, there is a much wider range of available applications.
For this scenario you will need a virtual machine host running a hypervisor such as Microsoft Hyper-V. The system's connection broker knows which virtual machine to offer the user and manages the processes of authentication with a directory service, or similar.
It then connects the client to the right machine, which might be running on one of many hosts. Because the user has established a connection with the broker, reconnecting in the event of a dropped link is simplified: all it needs to do is re-establish the link from one of its cached sessions. IT admins can manage the process with Microsoft System Center.
It is all very different from dumping a box on users' desks and leaving them to install the operating system and get themselves up and running.
Virtualisation makes desktop management easier and, for a wide range of users, offers a good compromise between local processing that delivers the full-fat media experience and a desktop focused on the task at hand. ®