[amsat-bb] Re: Australian Reciprocal Licensing Changes

Howard Long howard at howardlong.com
Sat Feb 9 01:52:04 PST 2008

Hi Nate

> > Among the changes they now permit the Encoding, for the purpose of 
> > Obscuring the meaning, of control signals for Amateur Satellites or 
> > unattended stations.
> All I have to say to this is FINALLY...
> > Now, signals encoded for the purpose of obscuring the meaning may be 
> > used for controlling a satellite or an unattended amateur stations or 
> > in emergency operations.
> Another VERY important piece of this:  Can also be used for emergency 
> operations TRAINING.  (Train like you're going to fight... so to speak.)

I am not sure what the purpose of obscuring the meaning is. For command and
control, is a digital signature not sufficient? Implemented with a
continually changing challenge-response combined with a private key, this
would prevent the resending of recorded commands doing damage.

The only reason I can see for encryption is to protect NPPI data during
emergencies, but I don't understand why it's needed for command and control.

Of course, there may be another reason for obsuring the meaning that I've

73, Howard G6LVB

More information about the AMSAT-BB mailing list