What's the real scope of hardware openness?

[Mikko J Rauhala]

On ma, 2007-08-06 at 13:26 +0200, Luca Dionisi wrote:
> I have a likely silly question.

Not that silly, though the context is wrong. Doesn't have that much to
do with hardware openness.

> I mean, what if each phone in a neighborwood could be used as
> a "radio-bridge" in order for a caller to find a path to a callee
> without having to rely on a network operator and pay for it?

The calls would be less reliable with lower quality of service, the
problems increasing with the number of simultaneous callers, plus their
phones would eat up power like crazy.

> I thought that the absence of this feature was a limitation
> imposed on the user from the phone builders. So when I saw the
> FIC initiative I thought that this kind of openness could lead
> to the possibility of such a scenario.

With GTA02, you should be able to do Wifi mesh networking and route VOIP
calls through that, if you like. Just that, well, see above. (With
GTA01, all you have is Bluetooth, and while it's suitable for a lot of
stuff, let's just not.)

What you can't do is use the GSM frequencies for this kind of thing,
first because you don't have access to the GSM chip firmware, and second
because transmitting on the GSM spectrum without timeslot allocations
from the cell tower will cause you to interfere with people's calls,
some of them emergency ones. Plus the illegality of it all.

-- 
Mikko J Rauhala <mjrauhal at cc.helsinki.fi>
University of Helsinki