Microsoft reinvents the mainframe

Bill Laing, Microsoft’s corporate vice president in charge of the Server and Solutions Division, told a roomful of reporters yesterday, “My desktop today is a thin client ... and I’m pretty happy with it.” Coming from the company whose Windows OS has been synonymous with the fat client for decades, that’s a profound admission. But it’s a measure of how much Microsoft has changed in recent years that he could make that statement and barely raise an eyebrow.

What technology is Microsoft using to power a thin client good enough to stand in for a full-fledged Windows PC? It’s called RemoteFX. It works hand in hand with Hyper-V virtualization, and it’s one of a handful of new capabilities that are being grafted into the upcoming Service Pack 1 for Windows Server 2008 R2 and Windows 7. (These new Hyper-V server capabilities are the only new features included with SP1. For Windows 7, which shares the same code base, SP1 will include no new features, just bug fixes and roll-ups of updates already being delivered via Windows Update.)

Over the weekend, I saw a preview of the RemoteFX technologies that were officially unveiled at Microsoft’s Tech-Ed conference in New Orleans this morning. Collectively, they solve some of the nagging issues that have made virtual desktops second-class citizens to PCs.

RemoteFX starts with a Windows Server running Hyper-V. It virtualizes the graphics for each VM—including high-definition video, the full Aero interface, and even high-end apps like AutoCAD—and then sends that output to the remote client using a new codec, which can run in hardware or software. A single graphics card on the server can handle the graphics needs of multiple virtual guests, which need only low-end graphics hardware and a Virtual GPU driver that will come with the new Remote Desktop client in Service Pack 1 for Windows 7 Ultimate  and Enterprise editions. (The RemoteFX code also runs on similar editions of Windows Vista, but not on Windows XP.)

SP1 will also deliver a couple of other big improvements aimed at virtual desktops. First up is support for a broad range of USB devices. The list includes webcams, VOIP headsets, biometric hardware, Windows Mobile devices, and even multi-function printers and scanners, which previously didn't work at all with virtual machines. Plug one of those USB devices into a thin client connected to a Hyper-V machine (where both ends of the connection are using RemoteFX) and you’ll be able to use the devices with your virtual desktop. The other major improvement is the option to dynamically assign memory to a virtual machine. A VM can start with a minimal amount of memory, add virtual RAM on the fly as apps need it, and give up the virtual RAM to the system when other apps need it more. Dynamic memory solves a common virtualization problem in a way that’s surprisingly graceful for desktop clients. (It solves the same problem as VMWare's Memory Overcommit feature.)

The goal, at least for enterprises, is to move a group of users and their Windows desktops off of PCs and onto a single server. With those desktops running on a single server, Microsoft argues, you can replace relatively expensive PCs with small devices that have basic graphics hardware, a handful of USB ports, and just enough processing power to run a Remote Desktop session. One such device that Microsoft showed yesterday is a tiny green box that uses a mere 3W of power under load and weighs less than a pound. Sprinkle a few of those around an office or department connected to a Hyper-V server and you suddenly have something very close to an old mainframe environment, with “terminals” that are smarter than their ancestors but still less expensive than PCs, with far less maintenance required.

One big question is how much demand Microsoft is likely to find for RemoteFX. Although running AutoCAD on a virtual machine makes an impressive demo, it’s likely that most companies running a high-end drafting program will still want to do so on dedicated hardware—in other words, a PC. A more realistic scenario is to replace a basic business PC with a smaller, cheaper device that still delivers the full PC experience.

The other big question is how much video hardware you’ll need for a server that’s capable of driving the displays on multiple guests. The good news, as Laing explained, is that RemoteFX is GPU-agnostic; it will work with any modern graphics card with enough video RAM. The irony is that it requires adding high-end graphics support to servers, which have historically been equipped with only the most basic video hardware. Microsoft recommends setting aside 150-200 MB of VRAM for each virtual desktop.

In its announcement today, Microsoft said SP1 will be available as a beta in July. It didn’t assign a date for when SP1 would be released, cautioning customers: “Continue your testing and deployment of Windows 7. Don’t wait for Service Pack 1.” They also readily acknowledge that RemoteFX is still in its early phases—an understatement, to be sure.

Where Microsoft’s ambition was once to put a PC on every desktop, in 2010 they’ll settle for delivering a desktop to you over a network, on a device that might or might not be a PC. That’s an enormous change.