When I attended TechEd 2012 in Amsterdam at the end of June, the Windows To Go session was likely the most attended session all day. And it's easy to see why.
Windows To Go allows enterprise users to deploy a bootable Windows 8 environment onto a USB flash drive. It's not a trimmed-down version of Windows (like many Linux boot environments are), but a full-blown copy of Windows 8 including all the features you need. It is sealed off from the physical machine (well, sort of, more on that below) and can be protected using BitLocker.
At TechEd, I was given a 32 GB Windows To Go drive (by Kingston). Over the course of a couple of days, I lived and breathed Windows To Go. I used it productively on my main laptop, test rigs and even desktops at clients' offices. Here's what I found:
Creating a Windows To Go drive
In Windows 8 Enterprise, Microsoft will include an easy-to-use Windows To Go workspace creator. According to what I've been told by team members of the Windows To Go group at Microsoft, this wizard will apparently also allow you to pre-install some applications (they didn't say what kind) and preload it with data. However, if you desperately want to try it out, these instructions should help. Just make sure your thumb drive is fast enough in the random 4k read/write department and has enough space (32 GB+). External hard disks should also work but they rarely deliver the performance you need for a Live OS.
Working across several machines
I almost exclusively worked off of the USB thumb drive and Windows To Go over the course of a week. Guess what: It worked on every single device -- no matter if I plugged it into a 5 year old Core 2 Duo with 2.66 GHz and an old BIOS (that barely supports USB boot) or into my high-end gaming rig. It adapted to every single hardware configuration I threw it at and, aside from the initial configuration dialogue and driver installations that occur during the first boot on a new machine, it worked in each and every instance.
Windows To Go saves the driver configuration so you won't see the initial driver installation/update process on a machine twice. However, I soon discovered one very real problem: Booting into Windows To Go might not always be so easy since fiddling around with BIOS/UEFI of various PCS (at corporations, friends' homes, internet cafés, etc.) may not be possible at all.
Unplugging the drive
The first thing I did (and I imagine anyone with a Windows To Go drive will do) is unplug the drive to see what will happen. Fortunately, Microsoft made changes to its file system stack and kernel drivers that allow this specific scenario. Once the drive is removed, Windows 8 just freezes. When you plug the drive back in, it continues to work as if nothing ever happened. However, after 60 seconds of non use, Windows 8 assumes that you're gone and shuts down the machine.
I encountered some weird issues on one of my desktop systems (an Alienware gaming rig) in which Windows To Go would run for a few seconds and then just freeze up. I assume this is a beta bug but it was a good reminder to save all my files before I tried unplugging.
I also found that Windows To Go is extremely sensitive to improper shutdowns. Each and every time I forced the PC to shut down, I was presented with a "chkdsk" dialog that sat there for many minutes scanning the thumb drive for errors.
Physical hard disks: Hidden?
Microsoft hides the internal hard disk on any machine by default so that Windows To Go can't be used as a hacking device to get quick access to data on a physical disk:
However, using "diskmgmt.msc" makes getting around this all too simple: Just select the physical partition and mark it as "Online" and you'll get instant access. Of course, the local user folder will still be protected but all other files are easily accessible.
You could do this with any bootable Linux and Windows environment so Windows To Go isn't any more of a security risk, but it isn't any less either.
Working with the Windows 8/Office 2013 cloud
Having signed into my Microsoft Account (what used to be called Windows Live ID), all my language settings, keyboard preferences, wallpaper, themes and various other settings got applied almost instantly. I felt at home. Once I set up all my applications, I couldn't really tell whether I was working with the physical machine or the USB thumb drive.
Next up: I launched Office 2013 on the Windows To Go drive. Since I already signed up for the Microsoft Account, Office 2013 recognized my ID and immediately applied all my Office preferences and connected me to my SkyDrive folder. Within seconds I had access to all my files in the cloud.
I was afraid that, even on a USB 3.0 machine, I would encounter performance problems -- especially during heavy multitasking. But that didn't happen. I had about 30 tabs open in Internet Explorer, basically all Office applications, Photoshop, iTunes, etc. and did not see a massive difference in responsiveness when compared to the physical Windows installation on the same machine.
What I did notice, however, was an occasional brief freeze. It happened mainly when opening the context menu, switching between browser tabs or even when typing. But overall responsiveness and multitasking was almost on par with the physical machine.
Obviously, another area where performance matters is boot up. First, I tested Windows To Go on my dedicated work machine at the office of one of my clients: A desktop PC equipped with a Core 2 Duo 3 GHz, 4 GB RAM and a 7200 RPM drive. While Windows 7 Enterprise took nearly 47 seconds to boot, the Windows To Go drive just needed 32 seconds (and that's via USB 2.0, mind you).
On my dedicated Windows 8 tablet, the Samsung Series 7, Windows To Go took about twice as long -- but since we're talking 8 seconds versus 15 seconds here, I'm not exactly complaining.
Setting up applications shows where even a high-speed USB 3.0 thumb drive fails: The installation of Office 2013 Professional Plus took about 5 minutes, whereas it didn't even need 2 minutes to install on the physical machine. I assume the flash controller couldn't handle both the load of the OS (file system) as well as the extraction and reads/writes of the installation.
Working with applications proved to be snappy as well. Only on machines with USB 2.0 did I notice much of a delay when launching applications, but once loaded into memory, they were as snappy as on the physical machine:
I also put both both Windows 8 and Windows To Go through the entire suite of PCMark 7 tests. PCMark is a popular benchmark designed to measure overall system performance (CPU, hard disk, graphics) by simulating real-world scenarios such as browsing websites, copying/pasting huge amounts of text, rendering video files, gaming, scanning for viruses, etc.
I repeated these tests several times and the results were the same: I lost quite a bit of performance (nearly 300 points) most likely due to the fact that the USB 3.0 drive didn't achieve the same throughput as the built-in SSD of the Core i5 Samsung tablet I used for testing.
Overall, the performance differences were negligble and barely noticeable in day-to-day usage.
Disk space becomes a luxury item
With my review unit being just a 32 GB thumb drive, I instantly noticed where Windows To Go quickly hits its limits: Having installed all my most critical applications, I was left with about 8 GB of free space. I'm not sure how much of an issue this will be for enterprise users, since Windows To Go is designed for scenarios in which users won't be handling massive amounts of data (you won't hand your CFO or Creative Director a Windows To Go stick and tell him to scrap his desktop). Also, as I mentioned earlier, SkyDrive makes up for a lot of that shortfall in storage space. I went with the 125 GB option and didn't miss the local storage as much thanks to my 100 Mbps connection (I guess I'd quickly change my mind if I had sub-10 Mbps speeds).
Bottom line: My "emergency" Windows 8
Overall, I came away impressed: Windows To Go offers the entire Windows 8 functionalty on a handy USB thumb drive. This should make things easier for any IT pro who would rather carry a USB stick than a laptop. What I don't understand is why Microsoft hasn't talked licensing yet and why this feature is strictly enterprise. I assume Microsoft will open up Windows To Go for a broader audience sometime in the future. Until then I can only advise admins to take a look and evaluate how Windows To Go could ease some of their BYOD (bring your own device) pains.