Is there a unique device identifier in .NET MF?

I would like to be able to identify my devices without having to hard-code a unique identifier in the code. I was thinking that there would be some sort if Guid that is stamped into each model that I could access via code. Am I crazy to think that this is possible? I am working with the fez dominos and the fez mini. Thanks!

Not built in but you can simply add a one wire device that dies just that and more for cheap.

yeah add a one-wire DS18B20+ and you get a unique id. But not many mainboards have those on them do they Gus (hint hint :slight_smile: )

Less expensive and less power consumming is the ds2401.

Depending on the main board there might be a MAC address. That will be unique.

Not sure what the .NETMF supports, but we have used the 96bit unique ID that is baked into all the ST Cortex parts as a sort of MAC before.
Is there some way to access these registers directly from .netmf?

Ignore this - don’t know if the NXP parts have this feature…

The problem is that mac address can be modified by software in most of modern devices… from the security point of view it is very poor, one wire devices can also be emulated…

Do you need security?

I don’t know if the micro .net framework SD card implementation supports DRM - but it is baked into the standard to have a password protected file store. Other devices can’t read it, they can only reformat the disk.

For security I like the DS28E01-100. It is a onewire device with SHA1 engine and write only secret.

You write the secret in. It can’t be read out. But it can be used as part of the SHA input to create an encrypted hash. That hash can be read back and compared to the hash calculated in netmf.

To prevent replay atacks you can seed the SHA with random values so the HASH isn’t always the same, but, knowing the secret, can be calculated.

I dont need security, these would be wifi temperature monitors using a fez mini serial connected to a roving networks wifly and I need everything as small as possible.

If you’re reading temperature, what sensor are you intending to use. DS18B20+ (the current produced device) are cheap easy and pretty small as well as having a unique code, so they seem to me to be the perfect solution to what you need !