General Instrument Corporation

Combined Conditional Access Development and Support, LLC

Michael W Johnson

Eric J Sprunk

An Tonthat

Madhusudhan R Penugonda

Systems and methods for dynamic data masking are disclosed. The disclosed methods and systems can be used to dynamically mask data in cryptographic operations, such as advanced encryption standard (AES) operations, data encryption standard (DES) operations or triple DES operations. Specifically, data in cryptographic operations can be covered with unlimited and continuously changing masks. As an example, the Substitution table, key schedule, and state register in AES, or key schedule and selection functions in a DES or triple DES can be covered with unlimited and constantly changing masks. In an aspect, dynamic masking operations can be combined with orbital RAM algorithm and no-operation clocks to make power signature analysis in cryptographic attacks even more difficult.

Systems and methods for dynamic data masking

According to the invention, a circuit that is capable of automated scan testing is disclosed. Included in the circuit are a cryptographic engine, a digital circuit, an input pin, and an output pin. The cryptographic engine capable of performing at least one of encryption and decryption of one or more digital signals. The digital circuit includes combinatorial logic and a number of memory cells. The memory cells have scan inputs connected serially in a scan chain. The input pin and output pin are coupled to the scan chain. At least one of the input pin and the output pin carries at least some cipher text data of the scan chain.

Secure scan

A smart card package includes two on-board batteries for providing uninterrupted power to a programmed, volatile memory unit. The first battery is a non-rechargeable battery with sufficient capacity to provide power to the volatile on-board memory during an initial storage period between programming the memory and deployment of the smart card. This initial storage period may be, for example, approximately two years. The second battery is a rechargeable battery that will be charged by the host device in which the smart card is deployed. The second, rechargeable battery can provide power to the volatile memory throughout the life of the card, after the first, non-rechargeable battery is dead. Specifically, the second, rechargeable battery can provide power to the non-volatile memory when needed during, for example, any subsequent storage period or during movement of the smart card between host devices.

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Escondido, CA, United States of America

Michael W Johnson