At 17:57 14.09.00 -0400, you wrote:
[snip]
>I don't know much about the internals of current cellphones, but it's not
>like it would be hard to build a secure cellphone service on top of
>existing cellphone systems.
If my memory serves me correctly, Starium was planning on doing exactly
this and selling those cell phones for about $100 each. IIRC were discussed
this in November of 1999 - can anyone comment on what happened since then?
[...]
>I suspect the real problem here is that once enough soldiers are using the
>local cellphone system, an enemy can either selectively deny service (it
>can't be too hard to listen for digital data, or even for data that
>consistently doesn't compress well, and kill those calls), or can just blow
>up, or cut power to the cellphone towers. This would be especially nasty
>in the middle of some attack, where suddenly the communications system
>stops working when you need to call for help or tell someone who's shooting
>at you to knock it off.
Agreed. This could -however- be prevented by using satellite cell phone
services, such as Globalstar or Inmarsat (just to name a few), the drawback
being the long signal propagation delay. Iridium, the company being closest
to offering global coverage, appears to be out of business though.
However, satelite-to-ground communications should be a lot harder to jam
than plain terrestrial cell phone-to-BTS (aka ground station) communication.
>I wonder how hard it is to maintain independent cellphone service via
>temporary towers or something.
Well, it can be done (and regularly is during e.g. expositions and other
big events) but this would probably be insufficient and very hard to
maintain in times of war.
-Jan
