China Science » Computer Science

Quantum Cryptography:A Survey

admin — Sat, 14 Jun 2008 14:46:22 +0000

We survey some results in quantum cryptography. After a brief introduction toclassical cryptography, we provide the quantum-mechanical background needed to present somefundamental protocols from quantum cryptography. In particular, we review quantum key distributionvia the BB84 protocol and its security proof, as well as the related quantum bit commitment protocoland its proof of insecurity.

DAGMAR BRUSS　GABOR ERDELYI　TIM MEYER　TOBIAS RIEGE　JOERG ROTHE
Institut fuer Theoretische Physik, Heinrich-Heine-Universitaet Duesseldorf,40225 Duesseldorf, Germany
quantum bit commitment quantum cryptography quantum key distribution

A Survey of RST Invariant Image Watermarking Algorithms

admin — Sat, 14 Jun 2008 14:44:50 +0000

In this article, we review the algorithms for rotation, scaling andtranslation (RST) invariant image watermarking. There are mainly two categories of RST invariantimage watermarking algorithms. One is to rectify the RST transformed image before conductingwatermark detection. Another is to embed and detect watermark in an RST invariant or semi-invariantdomain. In order to help readers understand, we first introduce the fundamental theories andtechniques used in the existing RST invariant image watermarking algorithms. Then, we discuss indetail the work principles, embedding process, and detection process of the typical RST invariantimage watermarking algorithms. Finally, we analyze and evaluate these typical algorithms throughimplementation, and point out their advantages and disadvantages.

DONG ZHENG　YAN LIU　JIYING ZHAO　ABDULMOTALEB EL SADDIK
Multimedia Communications Research Laboratory, School of InformationTechnology and Engineering, University of Ottawa, 800 King Edward Avenue, Ottawa, Ontario, K1N 6N5,Canada
digital image watermarking　 RST invariant　 fourier-mellin transform　 LPM　ILPM　 radon transform　 feature points template matching moments

A Taxonomy of Suffix Array Construction Algorithms

admin — Sat, 14 Jun 2008 14:35:40 +0000

In 1990, Manber and Myers proposed suffix arrays as a space-savingalternative to suffix trees and described the first algorithms for suffix array construction anduse. Since that time, and especially in the last few years, suffix array construction algorithmshave proliferated in bewildering abundance. This survey paper attempts to provide simple high-leveldescriptions of these numerous algorithms that highlight both their distinctive features and theircommonalities, while avoiding as much as possible the complexities of implementation details. Newhybrid algorithms are also described. We provide comparisons of the algorithms’ worst-case timecomplexity and use of additional space, together with results of recent experimental test runs onmany of their implementations.

SIMON J. PUGLISI　W. F. SMYTH　ANDREW H. TURPIN
School of Computer Science and Information Technology, RMIT University, GPOBox 2476V, Melbourne V 3001, Australia

suffix array　 suffix tree suffix sorting burrows-wheeler transform

Survey of Network-Based Defense Mechanisms Countering the DoS and DDoSProblems

admin — Sat, 14 Jun 2008 14:33:50 +0000

This article presents a survey of denial of service attacks and the methodsthat have been proposed for defense against these attacks. In this survey, we analyze the designdecisions in the Internet that have created the potential for denial of service attacks. We reviewthe state-of-art mechanisms for defending against denial of service attacks, compare the strengthsand weaknesses of each proposal, and discuss potential countermea-sures against each defensemechanism. We conclude by highlighting opportunities for an integrated solution to solve the problemof distributed denial of service attacks.

TAO PENG　CHRISTOPHER LECKIE　KOTAGIRI RAMAMOHANARAO
botnet　 bandwidth attack　 DNS reflector attack　 DoS　 DDoS　 internet security　IP spoofing　 IP traceback　 IRC　 resource management SYN flood VoIP security

Compressed Full-Text Indexes

admin — Sat, 14 Jun 2008 14:32:40 +0000

Full-text indexes provide fast substring search over large text collections.A serious problem of these indexes has traditionally been their space consumption. A recent trend isto develop indexes that exploit the compressibility of the text, so that their size is a functionof the compressed text length. This concept has evolved into self-indexes, which in addition containenough information to reproduce any text portion, so they replace the text. The excitingpossibility of an index that takes space close to that of the compressed text, replaces it, and inaddition provides fast search over it, has triggered a wealth of activity and produced surprisingresults in a very short time, which radically changed the status of this area in less than 5 years.The most successful indexes nowadays are able to obtain almost optimal space and search timesimultaneously. In this article we present the main concepts underlying (compressed) self-indexes.We explain the relationship between text entropy and regularities that show up in index structuresand permit compressing them. Then we cover the most relevant self-indexes, focusing on how theyexploit text compressibility to achieve compact structures that can efficiently solve various searchproblems. Our aim is to give the background to understand and follow the developments in this area.

GONZALO NAVARRO　VELI MAEKINEN
text indexing text compression entropy

A Survey on Peer-to-Peer Key Management for Mobile Ad Hoc Networks

admin — Sat, 14 Jun 2008 14:30:44 +0000

The article reviews the most popular peer-to-peer key management protocolsfor mobile ad hoc networks (MANETs). The protocols are subdivided into groups based on their designstrategy or main characteristic. The article discusses and provides comments on the strategy of eachgroup separately. The discussions give insight into open research problems in the area of pairwisekey management.

JOHANN VAN DER MERWE　DAWOUD DAWOUD　STEPHEN McDONALD

mobile ad hoc networks　 security peer-to-peer key management pairwise keymanagement