There's currently a sticking point with how one should represent a Bluetooth device in one's Foaf file from a perspective of both privacy and spoof-a-bility. A Bluetooth device effectively has two id's; one is a user-changeable text field typically "Jims Phone" or more frequently a factory default like "Nokia 3650" and the other id is a 12 digit hex identifier not dissimilar in concept to a network card's MAC address.

Both of these are modifiable (although the hex id is rarely changeable in a mobile phone) so spoofing is always a posibility. One solution that would make spoofing harder would be if the Foaf file was to contain a hash or checksum of both ids, this would be hard to replicate unless one had seen both the ids, but this would make generating the entry in the Foaf file entry more difficult.

Privacy is going to be tricky, although there's always ways of mitigating this:

• Don't put any Bluetooth information in your Foaf
• Restrict your Foaf to a trusted community
• Don't turn your Bluetooth on

Another thought - maybe it would be useful to put something easily identifiable in the user modifiable field primarily as an advert for FoafMobile, but maybe also to help FoafMobile apps know that this Bluetooth ID really is worth looking up. I'm proposing a user identifier something like "FoafMob Jims Mobile" actually how about "FoaM"? Short, sweet, and it should be easy to type with T9 text entry.