> In the US, the different cellphone standards support different crypto,
> and some cell companies or cell sites don't use it.
So far I have *never* found a US TDMA cellphone site that supports
encryption. I have it enabled in my Nokia phone, and every time I make a
call, it beeps at me to tell me "voice privacy not available".
I use an AT&T Digital One phone. Matt Blaze spent a year finding the
right guy inside AT&T who's responsible for this utter abomination.
He was unable to get him to change it, and eventually gave up. I
think we c'punks should try.
Note well the danger of having "optional" encryption in a major
protocol. I don't just mean protocols that let the user turn it on or
off. I mean protocols where there's a maintenance mode that turns it
off "briefly, for the duration". Telcos are so used to being under
NSA's and FCC's thumb that they will turn off customer privacy
permanently, without even being told to.
Years of work in standards committees and years of technical work can
all go for naught, when those responsible for operating the service are
untrustworthy. End-to-end encryption is your friend; it needs to get
designed into some cellphones.
John
