TR> If you change the codes on the newer equipment every ten seconds, they
 TR> would have to develop something super fast that would cost mega-bucks.
BB> If you changed the code every 10 seconds on encrypted units,
BB> the agency is overly paranoid.  It does take manual
BB> intervention, although it can be done in bulk, and over the
BB> air.
There are radios, I don't know if they can be used for
police dispatching, that can be programmed to
automatically change the key at set periods of time.
It was explained to me as being something like PGP's
encryption system.  Don't ask me much more because
that's about all I know on the tech side.  I'm like
most people, I turn on the radio and do what they told
me and it works.
BB> However, scrambling, as compared to encryption, is MUCH less
BB> secure. 
BB> If your agency is looking at anything other than encryption,
BB> then they need some serious help!
Most people use scrambling and encryption
interchangeably.  I usually do.
                      Remember:  Freedom isn't Free!
--- timEd-B11
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