Mostafa M. I. Taha

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NIST recently completed the SHA-3 competition with the selection of Keccak as the new standard for crypto-graphic hashing. In this paper, we present a comprehensive Side-Channel Analysis of Keccak, when it is used with a secret key to generate a Message Authentication Code (MAC) (MAC-Keccak). Our analysis covers all the variations of the algorithm. We show(More)
Many commercial systems in the embedded space have shown weakness against power analysis based side-channel attacks in recent years. Designing countermeasures to defend against such attacks is both labor intensive and error prone. Furthermore, there is a lack of formal methods for quantifying the actual strength of a countermeasure implementation. Security(More)
Recent research has demonstrated that there is no sharp distinction between passive attacks based on sidechannel leakage and active attacks based on fault injection. Fault behavior can be processed as side-channel information, offering all the benefits of Differential Power Analysis including noise averaging and hypothesis testing by correlation. This paper(More)
Side-channel analysis (SCA) exploits the information leaked through unintentional outputs (e.g., power consumption) to reveal the secret key of cryptographic modules. The real threat of SCA lies in the ability to mount attacks over small parts of the key and to aggregate information over different encryptions. The threat of SCA can be thwarted by changing(More)
Many commercial systems in the embedded space have shown weakness against power analysis-based side-channel attacks in recent years. Random masking is a commonly used technique for removing the statistical dependency between the sensitive data and the side-channel information. However, the process of designing masking countermeasures is both labor intensive(More)
Keccak is a hashing function selected by NIST as the SHA-3 standard. Keccak provides an interesting opportunity to have a single core that can perform hashing, MAC generation, authenticated encryption and more. For all applications that involve processing of a secret key, side-channel protection should be considered. Indeed, Keccak authors proposed(More)
The security threat of side-channel analysis (SCA) attacks has created a need for SCA countermeasures. While many countermeasures have been proposed, a key challenge remains to design a countermeasure that is effective, that is easy to integrate in existing cryptographic implementations, and that has low overhead in area and performance. We present our(More)
We propose a novel application adaptive (multi-mode) headway-based broadcasting protocol that is most appropriate for public-safety applications in VANETs. Being headway-based, the proposed protocol possesses unique robustness at different speeds and traffic volumes. Moreover, it addresses application differences with a new multi-mode feature. The logic(More)