Re: Wavelets and Encryption

From: Andrew Swallow (am.swallow_at_eatspam.btinternet.com)
Date: 05/06/03 

Date: Tue, 6 May 2003 00:51:37 +0000 (UTC)

To use frequency hopping as a form of encryption you have to send
at least two signals. The real one and the fake(s). Hop them all so
that the interceptor cannot work out which is the real signal. A single
hopping transmitter can be beaten by using a wide band receiver
that accepts all the frequencies. An alternative break is to use say a
thousand receivers, each on a different frequency, and forward
changers in signal power.

To use a one time pad as the frequency decider, examine the
frequency hopping circuit. You should have a digital way of deciding
the next frequency and a way of jumping to that frequency. Remove
the digital feed back circuit and replace it with something that
reads your one time pad. You will need a way of synchronising
the hoppers, possibly by sending a plain text header containing
the table offset at the start of every hop.

Andrew Swallow

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