| Thomas Peyrin |  |
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Date de l'exposé : 3 février 2012
Recent Advances on Lightweight Cryptography Designs
The expected massive deployment of RFID technology in industry and everyday life raises new concerns and new challenges for the security community. Currently developed security protocols assume the existence of symmetric-key algorithms and there is thus a need for lightweight alternatives to currently standardised functions. In this talk, we will review the current situation and especially recent advances in regards to lightweight cryptography, focusing on block ciphers and hash functions. After remarking that designing lightweight cryptography is mostly a matter of reducing the memory usage, we will recall existing hash function constructions and explain how the recent sponge functions and some generalisations can limit the memory required in some scenarios. Then, we will study basic design choices for lightweight cryptography and introduce a new primitive for diffusion purposes. This new diffusion layer is basically the application of a Maximum Distance Separable matrix which can be computed serially in a very lightweight manner. Using these state-of-the-art techniques, we finally propose the hash function PHOTON and the block cipher LED, currently among the smallest cryptography primitives of their kind and offering strong security arguments against all known attacks.
