Martin Novotný

Learn More
The Hitag2 stream cipher is used in many real world applications, such as car immobilizers and door opening systems, as well as for the access control of buildings. The short length of the 48-bit secret key employed makes the cipher vulnerable to a brute-force attack, i.e., exhaustive key search. In this paper we develop the first hardware architecture for(More)
Cryptanalysis of ciphers usually involves massive computations. The security parameters of cryptographic algorithms are commonly chosen so that attacks are infeasible with available computing resources. Thus, in the absence of mathematical breakthroughs to a cryptanalytical problem, a promising way for tackling the computations involved is to build(More)
In this diploma thesis we present a real-world hardware-assisted attack on the well-known A5/1 stream cipher which is (still) used to secure GSM communication in most countries all over the world. During the last ten years A5/1 has been intensively analyzed [BB06, BD00, BSW01, EJ03, Gol97, MJB05, PS00]. However, most of the proposed attacks are just of(More)
We present two architectures of digit-serial normal basis multiplier over GF(2<sup>m</sup>). Proposed multipliers are scalable by the digit width of general value in difference of the multiplier of Agnew et al., that may be scaled only by digit width that divides the degree m. This helps designers to trade area for speed e.g. in cryptographic systems, where(More)
The PRESENT cipher is a symmetric block cipher with 64 bits of data block and 80 (or 128) bits of key. It is based on Substitution-permutation network and consists of 31 rounds. PRESENT is intended to be implemented in small embedded and contactless systems, thus its design needs only small amount of chip area and consumes low power. In this work we(More)