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Rolling code format cannot be learnt

Over the past few months, QD Electronics has heard that certain manufacturers of code learning receivers claim that they can learn the proprietary rolling code format of the Codex system. "These claims are a complete fallacy and only serve to both confuse the security industry as well compromise the security of the unsuspecting end-user," assures Mel Labuschagne, sales and marketing director of QD Electronics.

QD managing director, Tom Kenny, explains, "The Codex Transmitter transmits a 66-bit code word when a button is pressed. This 66-bit word is constructed from a fixed code portion and an encrypted code portion. The 32-bits of encrypted code data are generated from four button bits, 12 discrimination bits and a 16-bit sync value. The encrypted portion alone provides up to 4-billion changing code combinations. The 34-bits of fixed code data are made up of two status bits, four button bits and a 28 bit serial number.

"The fixed and encrypted sections combined increase the number of code combinations to 7,37 x 1019. The code learning receivers capture the 34 bits of the fixed code data and discard the 32-bits of encrypted rolling code data as random noise, since no stable pattern can be detected."

In essence, any customer using such a system has reduced his security to the level of a fixed code system (such as any typical binary system) which is not compliant with SAIDSA Bylaw 25 specifications relevant to domestic, commercial, retail and industrial installations.

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