21 research outputs found

    A survey of agent-oriented methodologies

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    This article introduces the current agent-oriented methodologies. It discusses what approaches have been followed (mainly extending existing object oriented and knowledge engineering methodologies), the suitability of these approaches for agent modelling, and some conclusions drawn from the survey

    Reduction of space complexity based on symmetric TMVP

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    Amplifying side channels through performance degradation

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    Interference between processes executing on shared hardware can be used to mount performance-degradation attacks. However, in most cases, such attacks offer little benefit for the adversary. In this paper, we demonstrate that software-based performancedegradation attacks can be used to amplify side-channel leaks, enabling the adversary to increase both the amount and the quality of information captured. We identify a new information leak in the OpenSSL implementation of the ECDSA digital signature algorithm, albeit seemingly unexploitable due to the limited granularity of previous trace procurement techniques. To overcome this imposing hurdle, we combine the information leak with a microarchitectural performancedegradation attack that can slow victims down by a factor of over 150. We demonstrate how this combination enables the amplification of a side-channel sufficiently to exploit this new information leak. Using the combined attack, an adversary can break a private key of the secp256k1 curve, used in the Bitcoin protocol, after observing only 6 signatures-a four-fold improvement over all previously described attacks.Thomas Allan, Billy Bob Brumley, Katrina Falkner, Joop van de Pol, Yuval Yaro
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