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Two Countermeasures Against Hardware Trojans Exploiting Non-Zero Aliasing Probability of BIST

The threat of hardware Trojans has been widely recognized by academia, industry, and government agencies. A Trojan can compromise security of a system in spite of cryptographic protection. The damage caused by a Trojan may not be limited to a business or reputation, but could have a severe impact on public safety, national economy, or national security. An extremely stealthy way of implementing ha

Trusted computing for infrastructure

The Networked Society is built on a complex and intricate infrastructure that brings distributed services, data processing and communication together, combining them into an innovative and more meaningful set of services for people, business and society. Trusted computing technologies will play a crucial role in meeting the security expectations of users, regulators and infrastructure owners. User

The qualitative modeling and compression of the request sequences in ARQ protocols

Compression of the repeat request data in ARQ protocols was studied. Focus was on the problem of compressing the output of the block box (ARQ algorithm) with unknown input signal (error sequence). Towards finding a practical solution, it was found that the main statistical properties of error sequences and xn are more less the same.

Some notes on the context mapping function in lossless data compression

One of the major challenges when applying (serial) universal source coding to 2-dimensional data, e.g., images, is to determine suitable context data. For this reason the concept of Context Mapping Function (CMF) has been introduced. In this paper we discuss the foundation for CMFs as well an off-line construction method via a combinatorial optimization method.

Notes on the P-content algorithm

The P-context algorithm as introduced by Weinberger and Seroussi (see IEEE Trans. Inform. Theory, p.1697-1706, 1996) offers a way to reduce the parameter description costs. This paper concerns a possible improvement of the P-context algorithm. By using weighting techniques an accurate redundancy bound is derived and a possible implementation is proposed.

A digital signature scheme based on random error-correcting codes

Over the past years there have been few attempts to construct digital signature schemes based on the intractability of the decoding of linear error-correcting codes. Unfortunately all these attempts failed. In this paper we suggest a new approach based on a seemingly unknown before fact that the set of correctable syndroms being nonlinear nevertheless contains a rather large linear subspace.

A lower bound on the probability of deception in multiple authentication

New bounds are derived for the probabilities of successful attack on multiple authentication schemes by removing the frequently assumed 'freshness' constraint on the source states. We prove that the overall probability of successful deception, PD(L), for a sequences of L uses of the authentication channel, is bounded from below by max(k/v, 1/√b). We also show that if PD{L) = 1/√b, then the key ent

On a fast correlation attack on certain streaxn ciphers

In this paper we present a new algorithm for the recovery of the initial state of a linear feedback shift register when a noisy output sequence is given. Our work is focussed on the investigation of the asymptotical behaviour of the recovery process rather than on the construction of an optimal recovery procedure. Our results show the importance of low-weight checks and show also that the complexi

Windmill pn-sequence generators

A windmill generator is a high-speed sequence generator capable of producing blocks of v consecutive symbols in parallel. It consists of v feedback-shift registers linked into a ring. The sequences are identical to those produced by a linear feedback-shift register with feedback polynomial of the special ('windmill') form f(t) = α(tv) - tLβ(t-v), where α(t) and β(t) are polynomials of degree less

Windmill generators a generalization and an observation of how many there are

The windmill technique has several practical advantageous over other techniques for high-speed generation or blockwise generation of pn-sequences. In this paper we generalize previous results by showing that if f(t)=α(t v) − β(t −v)t L is the minimal polynomial of a pn-sequence, then the sequence can be generated by a windmill generator. For L = 1,..127, and ν = 4, 8, 16 such that L ≡ ±3 mod 8 no

Linear complexity profile of sequences over the field GF(Q)

Summary form only given. The author extends Reuppel's concept of the linear complexity profile of binary sequences to sequences over an arbitrary finite field and provides formulas for the expected linear complexity and its variance of sequences Sn of length n over GF(q). He shows that the variance approaches 1/q when q approaches ∞. He presents criteria that could be useful when using the linear

GENERAL CLASS OF WINDMILL POLYNOMIALS FOR FAST M-SEQUENCE GENERATION.

Summary form only given. The windmill technique is an attractive alternative to the Lempel-Eastman technique for fast m-sequence generation. The author has generalized the class of linear recurrence relations for which the windmill technique results in an m-sequence generator. A converse to a set of known necessary conditions has been obtained.

Keyed logic BIST for Trojan detection in SoC

As demonstrated by the recent attack on Intel's Ivy Bridge processor, the traditional Logic Built-In Self-Test (LBIST) methods do not provide adequate protection of SoC against malicious modifications known as hardware Trojans. In this paper, we introduce a simple but efficient countermeasure against hardware Trojans which exploits non-zero aliasing probability of LBIST. We propose to generate LBI

Incremental authentication of tree-structured documents

A new message authentication code (MAC) is described that exploits the tree structure present in many modern document formats, e.g. SGML and XML. The new code supports incremental updating of the cryptographic checksum in the process of making incremental changes to the document. Theoretical bounds on the probability of a successful substitution attack are derived. Through experimental results we

Fast message authentication using efficient polynomial evaluation

Message authentication codes (MACs) using polynomial evaluation have the advantage of requiring a very short key even for very large messages. We describe a low complexity software polynomial evaluation procedure, that for large message sizes gives a MAC that has about the same low software complexity as for bucket hashing but requires only small keys and has better security characteristics.

Fast authentication codes based on random polynomial residue classes

The verification of the authenticity of a text document or a datafile is one of the main applications of cryptographic techniques. A common used technique for this purpose is the application of a message authentication code (MAC). Usually the MAC computation has to be done in software. Based on the relationship between error-correcting codes and so-called families of almost universal hash function

Estimation of escape probabilities for PPM based on universal source coding theory

Some of the best compression ratios for text compression are provided by the PPM (prediction by partial matching) class of algorithms. These algorithms are based on arithmetic coding using a fixed-depth Markov chain model of the source, i.e., the subsequence of symbols generated in any state s of the source is assumed to be the output of a memoryless subsource w=w(s). One of the most crucial steps