Amateur code breakers challenged to decipher secret messages on Australian coin

Four layers of code cover limited edition 50 cent coin released for 75th anniversary of Australian cybersecurity agency

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Amateur code breakers have been invited to try to decipher secret coded messages on a limited edition of an Australian 50 cent coin.

The coin was released on Thursday to mark the 75th anniversary of the Australian Signals Directorate (ASD), the agency responsible for signals intelligence, cyberwarfare and cybersecurity.

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