DG: I understand that Windows CE is used very much in embedded devices and I've also heard of something called embedded NT. Some of our readers might be a little confused how those two compare in the embedded space.

JR: One [Windows CE] goes as small as 350 to 500K, depending on whether you want a networking stack. The other [NT] starts at 12 megabytes of ROM and then another 12 to 24 megabytes of sort of hard-disk space. So essentially there are huge differences in their memory characteristics. And so, obviously, NT is not going to find itself being built into this huge range of appliance devices that Windows CE is really, really targeted for. NT is finding itself more appropriately in the networking space where people want all of the services that it has. For instance, its proxy services. You'd put it in a headless networking situation where you don't need to monitor anything but you just want to have it embedded there. It can be a great, dedicated proxy server or a switch or something like that. So, it's moving more towards the industrial back-end functionality. It's also conceivable that it'd find its way into very high-end copiers, things of that nature. But there are size characteristics and there are memory characteristics. I'm really pushing them to two different ends of the embedded market.

DG: Is there a classic "this is exactly where embedded NT would be used" example? A handheld PC seems to be what many people think of when they think of Windows CE.

JR: First, I think that the handheld PC is a very limited view of what Windows CE is good for. First, I'd want to say that the way to think about Windows CE is that it's a modular operating system that essentially is broken into 120 different modules. Developers can take whichever of those modules that they want for whatever class of device that they want. And so, the device can reach the size, as I mentioned before, between about 500K if you have a networking stack, up to about 1.2 megabytes if you want to use the UI and some basic browser capabilities, and up to two megabytes if you want to use the pocket apps. So it can really be optimized for this huge range of devices, not just the H/PC. In terms of NT, the embedded NT I kind of highlighted earlier is ideally used for industrial networking type products.

DG: Like routers and things like that.

JR: You know, PBXs, routers, But the other point, not to make these answers incredibly long, is Windows CE…it's not to say Windows CE is not for industrial strength, we're finding Windows CE in factory automation and in other places. And in the future, as we get hard real-time functionality with it, it'll go into more and more of these sorts of industrial environments. Just different size constraints, that's all.

DG: So when people are thinking of Windows CE, they think of the word "Windows". And when the word "Windows" is used, people are thinking of a user interface. With Windows CE, we're talking about things like kernels and driver-level systems as well, which is why the AutoPC doesn't look a whole lot like our desktop.