Sökning: "Cryptography"

Visar resultat 1 - 5 av 33 avhandlingar innehållade ordet Cryptography.

  1. 1. Logics of Knowledge and Cryptography Completeness and Expressiveness

    Detta är en avhandling från Stockholm : KTH

    Författare :Mika Cohen; Mads Dam; Alessio Lomuscio; [2007]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; epistemic logic; first-order logic; formal cryptography; static equivalence; security protocols; BAN logic; multi-agent system; completeness; logical omniscience problem; TECHNOLOGY Information technology Computer science; TEKNIKVETENSKAP Informationsteknik Datavetenskap;

    Sammanfattning : An understanding of cryptographic protocols requires that we examine the knowledge of protocol participants and adversaries: When a participant receives a message, does she know who sent it? Does she know that the message is fresh, and not merely a replay of some old message? Does a network spy know who is talking to whom?This thesis studies logics of knowledge and cryptography. Specifically, the thesis addresses the problem of how to make the concept of knowledge reflect feasible computability within a Kripke-style semantics. LÄS MER

  2. 2. Two topics in cryptography lattice problems and the security of protocols

    Detta är en avhandling från Stockholm : KTH

    Författare :Mårten Trolin; Johan Håstad; [2005]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Datalogi; Datalogi; TECHNOLOGY Information technology Computer science Computer science; TEKNIKVETENSKAP Informationsteknik Datavetenskap Datalogi;

    Sammanfattning : In this thesis we present new results in two areas – cryptographic protocols and lattice problems.• We present a new protocol for electronic cash which is designed to function on hardware with limited computing power. The scheme has provable security properties and low computational requirements, but it still gives a fair amount of privacy. LÄS MER

  3. 3. Some Words on Cryptanalysis of Stream Ciphers

    Detta är en avhandling från Department of Information Technology, Lund Univeristy

    Författare :Alexander Maximov; [2006]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; VMPC; Dragon; Grain; A5 1; SNOW 2.0; Scream; large distributions; correlation attacks; distinguishing attacks; algorithms; Cryptography; cryptanalysis; RC4; RC4A; Computer science; numerical analysis; systems; control; Datalogi; numerisk analys; system; kontroll;

    Sammanfattning : In the world of cryptography, stream ciphers are known as primitives used to ensure privacy over a communication channel. One common way to build a stream cipher is to use a keystream generator to produce a pseudo-random sequence of symbols. LÄS MER

  4. 4. Cryptographic Tools for Privacy Preservation and Verifiable Randomness

    Detta är en avhandling från Department of Information Technology, Lund Univeristy

    Författare :Carlo Brunetta; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Confidentiality; Verifiable Randomness; Differential Privacy; GDPR; Privacy; Cryptography;

    Sammanfattning : Our society revolves around communication. The Internet is the biggest, cheapest and fastest digital communication channel used nowadays. Due to the continuous increase of daily communication among people worldwide, more and more data might be stolen, misused or tampered. LÄS MER

  5. 5. On the Design and Analysis of Stream Ciphers

    Detta är en avhandling från Department of Electrical and Information Technology, Lund University

    Författare :Martin Hell; [2007]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; weak feedback polynomials; bit-search generator; self-shrinking generator; Achterbahn; Pomaranch; Grain-128; Grain; stream ciphers; cryptography; cryptanalysis; Informatics; systems theory; Informatik; systemteori;

    Sammanfattning : This thesis presents new cryptanalysis results for several different stream cipher constructions. In addition, it also presents two new stream ciphers, both based on the same design principle. The first attack is a general attack targeting a nonlinear combiner. LÄS MER