International Association for Cryptologic Research

Displaying 1-40 of 447 results

  • White Papers // Dec 2014

    Security Weaknesses of an "Anonymous Attribute Based Encryption: Appeared in Asiaccs'13

    Attribute-Based Encryption (ABE) has found enormous application in ne-grained access control of shared data, particularly in public cloud. The researcher proposed a scheme called match-then-decrypt, where before running the decryption algorithm the user requires to perform a match operation with attribute(s) that provides the required information to identify whether a...

    Provided By International Association for Cryptologic Research

  • White Papers // Dec 2014

    Armadillo: A Compilation Chain for Privacy Preserving Applications

    "In parallel with the research work which has lead to dramatic improvements with respect to the computational overhead of homomorphic encryption the compilation and parallelism community has also started to grow a strong interest to homomorphic encryption techniques as a new execution environment for computer programs with a highly promising...

    Provided By International Association for Cryptologic Research

  • White Papers // Dec 2014

    Cryptanalysis of Full PRIDE Block Cipher

    "Due to the rapidly growing impact of mobile phones, smart cards, RFID tags and sensor networks, lightweight cryptography which is suitable for such resource-constrained devices becomes more and more important. PRIDE is a lightweight block ciphers designed by Albrecht et al., appears in CRYPTO 2014. The designers claim that the...

    Provided By International Association for Cryptologic Research

  • White Papers // Nov 2014

    Web Tap Payment Authentication and Encryption With Zero Customer Effort

    "In tap-card-pay application (app), the authors remove the keyboarding from the customer and add the simplicity of tapping the credit card on the Smartphone when the customer tries to checkout on the merchant's webpage. They propose a public-key authentication and encryption application that secures the messages between Tap-Card-Pay application, Tap-Card-Pay...

    Provided By International Association for Cryptologic Research

  • White Papers // Oct 2014

    A Proxy Re-Encryption Scheme With the Unforgeability of Re-Encryption Keys Against Collusion Attacks

    "Proxy Re-Encryption (PRE) schemes are cryptosystems which allow a proxy who has a re-encryption key to convert a cipher-text originally encrypted for one party into a cipher-text which can be decrypted by another party. In, Hayashi et al. proposed the new security notion for PRE called ""Unforgeability of Re-encryption Keys...

    Provided By International Association for Cryptologic Research

  • White Papers // Sep 2014

    Decoy-Based Information Security

    "In this paper, the authors discuss an emerging concept of decoy-based information security, or security without computational assumptions. In particular, they show how this concept can be implemented to provide security against (passive) computationally unbounded adversary in some public-key encryption protocols. In the world of symmetric cryptography, decoy-based security finds...

    Provided By International Association for Cryptologic Research

  • White Papers // Sep 2014

    A Survey of Fault Attacks in Pairing Based Cryptography

    "The latest implementations of pairings allow efficient schemes for pairing based cryptography. These make the use of pairings suitable for small and constrained devices (Smartphone's, smart cards) in addition to more powerful platforms. As for any cryptographic algorithm which may be deployed in insecure locations, these implementations must be secure...

    Provided By International Association for Cryptologic Research

  • White Papers // Mar 2014

    Efficient Fuzzy Search on Encrypted Data

    The authors study the problem of efficient (sub-linear) fuzzy search on encrypted outsourced data, in the symmetric-key setting. In particular, a user who stores encrypted data on a remote untrusted server forms queries that enable the server to efficiently locate the records containing the requested keywords, even though the user...

    Provided By International Association for Cryptologic Research

  • White Papers // Mar 2014

    Verifiable Delegated Set Intersection Operations on Outsourced Encrypted Data

    The authors initiate the study of the following problem: suppose Alice and Bob would like to outsource their encrypted private data sets to the cloud, and they also want to conduct the set intersection operation on their plaintext data sets. The straightforward solution for them is to download their outsourced...

    Provided By International Association for Cryptologic Research

  • White Papers // Mar 2014

    Non-Interactive Cryptography in the RAM Model of Computation

    Using recently developed techniques for program obfuscation, the authors show several constructions of non-interactive cryptosystems in the Random-Access Machine (RAM) model of computation that are asymptotically more efficient than what would be obtained using generic RAM-to-circuit compilation. In particular, let T denote the running time and n the memory size...

    Provided By International Association for Cryptologic Research

  • White Papers // Feb 2014

    Outsourcing Private RAM Computation

    The authors construct the first schemes that allow a client to privately outsource arbitrary program executions to a remote server while ensuring that: the client's work is small and essentially independent of the complexity of the computation being outsourced, and the server's work is only proportional to the run-time of...

    Provided By International Association for Cryptologic Research

  • White Papers // Feb 2014

    Reducing the Overhead of Cloud MPC

    The authors present a secure Multi-Party Computation (MPC) protocol in the honest-majority setting, which aims to reduce the communication costs in the situation where there are a large number of parties (as in a cloud scenario). Their goal is to reduce the usage of point-to-point channels, so as to enable...

    Provided By International Association for Cryptologic Research

  • White Papers // Feb 2014

    Garbled RAM Revisited Part II

    In EUROCRYPT 2013, Lu and Ostrovsky proposed the notion of Garbled RAM (GRAM) programs. These GRAM programs are analogous to the classic result of Yao's garbled circuits: a large encrypted memory can first be provided to evaluator, and then a program can separately be garbled and sent to an evaluator...

    Provided By International Association for Cryptologic Research

  • White Papers // Feb 2014

    Garbled RAM Revisited Part I

    The notion of garbled Random-Access Machines (garbled RAMs) was introduced by Lu and Ostrovsky (Eurocrypt 2013). It can be seen as an analogue of Yao's garbled circuits that allows a user to garble a RAM program directly, without performing the expensive step of converting it into a circuit. In particular,...

    Provided By International Association for Cryptologic Research

  • White Papers // Jan 2014

    Improved Differential Fault Attack on MICKEY 2.0

    In this paper the authors describe several ideas related to Differential Fault Attack (DFA) on MICKEY 2.0, a stream cipher from eStream hardware profile. Using the standard assumptions for fault attacks, they first show that if the adversary can induce random single bit faults in the internal state of the...

    Provided By International Association for Cryptologic Research

  • White Papers // Dec 2013

    Power and Timing Side Channels for PUFs and their Efficient Exploitation

    The authors discuss the first power and timing side channels on Strong Physical Unclonable Functions (Strong PUFs) in the literature, and describe their efficient exploitation via adapted Machine Learning (ML) techniques. Their method is illustrated by the example of the two currently most secure (CCS 2010, IEEE T-IFS 2013) electrical...

    Provided By International Association for Cryptologic Research

  • White Papers // Dec 2013

    Property Preserving Symmetric Encryption

    The authors proposed the notion of Property Preserving symmetric Encryption (PPEnc). They defined several security notions for PPEnc and studied their relationship. They also proposed a concrete scheme which preserves the orthogonality of encrypted vectors. The proposed construction is claimed to achieve the strongest security notion of property preserving encryption,...

    Provided By International Association for Cryptologic Research

  • White Papers // Dec 2013

    How to Keep a Secret: Leakage Deterring Public-key Cryptography

    How is it possible to prevent the sharing of cryptographic functions? This question appears to be fundamentally hard to address since in this setting the owner of the key is the adversary: they wishes to share a program or device that (potentially only partly) implements the users' main cryptographic functionality....

    Provided By International Association for Cryptologic Research

  • White Papers // Dec 2013

    Weakness of Several Identity-Based Tripartite Authenticated Key Agreement Protocols

    It is necessary to guarantee confidentiality, integrity and other security services for the communication parties over the open network. Key agreement allows multi-parties exchanging public information to create a common secret key that is known only to those entities over an insecure network. In recent years, several identity-based authenticated key...

    Provided By International Association for Cryptologic Research

  • White Papers // Dec 2013

    Chosen Ciphertext Secure (CCS): Symmetric Key CCA Encryption with Minimal Ciphertext Expansion

    In some wireless environments, minimizing the size of messages is paramount due to the resulting significant energy savings. The authors present a new symmetric encryption scheme: CCS or Chosen Cipher-text Secure scheme. CCS has the property that modifications to the cipher-text randomize the resulting plaintext. Using this property, they prove...

    Provided By International Association for Cryptologic Research

  • White Papers // Dec 2013

    CBEAM: Efficient Authenticated Encryption from Feebly One-Way Functions

    The authors show how efficient and secure cryptographic mixing functions can be constructed from low-degree rotation-invariant functions rather than conventional S-Boxes. These novel functions have surprising properties; many exhibit inherent feeble (Boolean circuit) one-wayness and offer speed/area trade-offs unobtainable with traditional constructs. Recent theoretical results indicate that even if the...

    Provided By International Association for Cryptologic Research

  • White Papers // Dec 2013

    Beyond Modes: Building a Secure Record Protocol from a Cryptographic Sponge Permutation

    Blinker is a light-weight cryptographic suite and record protocol built from a single permutation. Its design is based on the sponge construction used by the SHA-3 algorithm keccak. The authors examine the SpongeWrap authenticated encryption mode and expand its padding mechanism to offer explicit domain separation and enhanced security for...

    Provided By International Association for Cryptologic Research

  • White Papers // Dec 2013

    Lattice Signatures and Bimodal Gaussians

    The authors' main result is a construction of a lattice-based digital signature scheme that represents an improvement, both in theory and in practice, over today's most efficient lattice schemes. The novel scheme is obtained as a result of a modification of the rejection sampling algorithm that is at the heart...

    Provided By International Association for Cryptologic Research

  • White Papers // Dec 2013

    Functional Encryption for Randomized Functionalities

    Originally, encryption was thought of as a way to encrypt \"Point-to-point\" communication. However, in the contemporary world with cloud computing and complex networks, it has become clear that the people need encryption to offer more functionality. In this paper, the authors present the first definitions and constructions for functional encryption...

    Provided By International Association for Cryptologic Research

  • White Papers // Dec 2013

    Towards Leakage Exploitation Rate Optimality in Template Attack

    Template attack is widely accepted to be one of the most powerful side-channel attacks, because it is usually assumed that one has a full knowledge of the targeted crypto devices and thus be well capable of characterizing the side-channel leakages. However, the question of whether template attack is really optimal...

    Provided By International Association for Cryptologic Research

  • White Papers // Dec 2013

    RDAS: A Symmetric Key Scheme for Authenticated Query Processing in Outsourced Databases

    In this paper the authors address the problem of authenticated query processing in outsourced databases. An authenticated query processing mechanism allows a client to verify the validity of the query responses that it gets from an untrusted and remote server, who stores the client's database on its behalf. They introduce...

    Provided By International Association for Cryptologic Research

  • White Papers // Dec 2013

    Verifier-Based Password-Authenticated Key Exchange: New Models and Constructions

    While Password-Authenticated Key Exchange (or PAKE) protocols have been deeply studied, a server corruption remains the main threat, with many concrete cases nowadays. Verifier-based PAKE (or VPAKE) protocols, initially called augmented-PAKE, have been proposed to limit the impact of any leakage. However, no satisfactory security model has ever been proposed...

    Provided By International Association for Cryptologic Research

  • White Papers // Dec 2013

    Formal Analysis of CRT-RSA Vigilant's Countermeasure Against the BellCoRe Attack

    In the authors' paper at PROOFS 2013, they formally studied a few known countermeasures to protect CRT- RSA against the BellCoRe fault injection attack. However, they left vigilant's countermeasure and its alleged repaired version by the researcher as future work, because the arithmetical framework of their tool was not sufficiently...

    Provided By International Association for Cryptologic Research

  • White Papers // Dec 2013

    SPHF-Friendly Non-Interactive Commitments

    In 2009, the author proposed a reasonably practical Password-Authenticated Key Exchange (PAKE) secure against adaptive adversaries in the Universal Composability (UC) framework. It exploited the canetti-fischlin methodology for commitments and the cramer-shoup Smooth Projective Hash Functions (SPHFs), following the gennaro-lindell approach for PAKE. In this paper, the authors revisit the...

    Provided By International Association for Cryptologic Research

  • White Papers // Dec 2013

    Lower Bounds in the Hardware Token Model

    A protocol for secure two-party computation allows two mutually distrustful parties to jointly compute a function f of their respective inputs, x and y, in a way that does not reveal anything beyond the value f (x; y) being computed. Soon after the introduction of this powerful notion, it was...

    Provided By International Association for Cryptologic Research

  • White Papers // Dec 2013

    Leakage Resilient Fully Homomorphic Encryption

    The authors construct the first leakage resilient variants of Fully Homomorphic Encryption (FHE) schemes. Their leakage model is bounded adaptive leakage resilience. They first construct a leakage-resilient leveled FHE scheme, meaning the scheme is both leakage resilient and homomorphic for all circuits of depth less than some pre-established maximum set...

    Provided By International Association for Cryptologic Research

  • White Papers // Dec 2013

    On the Relation of Random Grid, Probabilistic and Deterministic Visual Cryptography

    Visual cryptography is a special type of secret sharing. Two models of visual cryptography have been independently studied: deterministic visual cryptography, random grid visual cryptography, introduced by the researchers. In the context of the deterministic model, the researcher has introduced a third model, the probabilistic visual cryptography model. The connection...

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  • White Papers // Dec 2013

    Strongly Secure One-Round Group Authenticated Key Exchange in the Standard Model

    One-round Group Authenticated Key Exchange (GAKE) protocols typically provide implicit authentication and appealing bandwidth efficiency. As a special case of GAKE - the pairing-based one-round Tripartite Authenticated Key Exchange (3AKE), recently gains much attention of research community due to its strong security. Several pairing-based one-round 3AKE protocols have recently been...

    Provided By International Association for Cryptologic Research

  • White Papers // Dec 2013

    Iterated Group Products and Leakage Resilience Against NC1

    The interplay between group theory and computational complexity has been the source of a number of elegant constructions and computational insights. A line of work [Bar89, CM87, BT88, BC92, CL94, Cle91, and IL95] in the late 1980s gave characterizations of various complexity classes in terms of products over finite groups....

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  • White Papers // Dec 2013

    A Note on Bilinear Groups of a Large Composite Order

    Weil pairing plays a key role in elliptic curve cryptography. The authors remark that the structure of bilinear groups of a large composite order (at least 1024 bits) could make group operation inefficient and lose the advantages of elliptic curve cryptography which gained mainly from smaller parameter size. As of...

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  • White Papers // Dec 2013

    Constant-Round Black-Box Construction of Composable Multi-Party Computation Protocol

    The authors present the first general MPC protocol that satisfies the following: the construction is black-box, the protocol is universally composable in the plain model, and the number of rounds is constant. The security of their protocol is proven in angel-based UC security under the assumption of the existence of...

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  • White Papers // Dec 2013

    NICV: Normalized Inter-Class Variance for Detection of Side-Channel Leakage

    Side-Channel Attacks (SCA) is considered a serious threat against embedded cryptography. Therefore security-critical chips must be tested for SCA resistance before deployment or certification. SCA are powerful but can need a lot of computation power, especially in the presence of countermeasures. The computation complexity of these attacks can be reduced...

    Provided By International Association for Cryptologic Research

  • White Papers // Dec 2013

    Between a Rock and a Hard Place: Interpolating Between MPC and FHE

    In the last few years computing on encrypted data via either Fully Homomorphic Encryption (FHE) or Multi-Party Computation (MPC) has been subject to a remarkable number of improvements. Firstly, FHE was shown to be possible; and this was quickly followed by a variety of applications and performance improvements. Secondly, whilst...

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  • White Papers // Dec 2013

    Tamper Resilient Circuits: The Adversary at the Gates

    In this paper the authors initiate the investigation of gate-tampering attacks against cryptographic circuits. Their model is motivated by the plausibility of tampering directly with circuit gates and by the increasing use of tamper resilient gates among the known constructions that are shown to be resilient against wire-tampering adversaries. They...

    Provided By International Association for Cryptologic Research

  • White Papers // Nov 2013

    Secure Multiparty Computations on BitCoin

    BitCoin is a decentralized digital currency, introduced in 2008, that has recently gained noticeable popularity. Its main features are: it lacks a central authority that controls the transactions, the list of transactions is publicly available, and its syntax allows more advanced transactions than simply transferring the money. This paper show...

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  • White Papers // Jun 2011

    Another Look at Security Definitions

    The authors take a critical look at security models that are often used to give "Provable security" guarantees. They pay particular attention to digital signatures, symmetric-key encryption, and leakage resilience. They find that there has been a surprising amount of uncertainty about what the "Right" definitions might be. Even when...

    Provided By International Association for Cryptologic Research

  • White Papers // Oct 2010

    Improved Ring Oscillator PUF: An FPGA-Friendly Secure Primitive

    In this paper, the authors analyze Ring Oscillator (RO) based Physical Unclonable Function (PUF) on FPGAs. They show that the systematic process variation adversely affects the ability of the RO-PUF to generate unique chip-signatures, and propose a compensation method to mitigate it. Moreover, a Configurable Ring Oscillator (CRO) technique is...

    Provided By International Association for Cryptologic Research

  • White Papers // Jun 2011

    On the (In)security of Hash-Based Oblivious RAM and a New Balancing Scheme

    With the gaining popularity of remote storage (e.g. in the Cloud), the authors consider the setting where a small, protected local machine wishes to access data on a large, untrusted remote machine. This setting was introduced in the RAM model in the context of software protection by Goldreich and Ostrovsky....

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  • White Papers // May 2011

    Cryptanalysis and Improvement of an Efficient CCA Secure PKE Scheme

    Recently in Chinese Journal of Computers, Kang et al. proposed an efficient CCA secure Public Key Encryption (PKE) scheme, and claimed that it is more efficient in the public/private keys than the famous CS98 and BMW05 CCA secure public key encryption scheme. However, in this paper the authors will show...

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  • White Papers // May 2011

    Framework for Security Proofs for On-Demand Routing Protocols in Multi-Hop Wireless Networks

    The authors present a framework for security proofs for on-demand routing protocols. The framework relies on the composable cryptographic library by Backes, Pfitzmann and Waidner (BPW). The idea is to break down the security requirement against the system (the protocol) into security requirement against the elements of the system, the...

    Provided By International Association for Cryptologic Research

  • White Papers // Jul 2011

    Cryptographic Analysis of All 4 X 4-Bit S-Boxes

    The authors present cryptanalytic results of an exhaustive search of all 16! bijective 4-bit S-Boxes. Previously affine equivalence classes have been exhaustively analyzed in 2007 work by Leander and Poschmann. They extend on this work by giving further properties of the optimal S-Box linear equivalence classes. In the main analysis...

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  • White Papers // May 2011

    Algebraic Cryptanalysis of the Round-Reduced and Side Channel Analysis of the Full PRINTCipher-48

    In this paper, the authors analyze the recently proposed light-weight block cipher PRINTCipher. Applying algebraic methods and SAT-solving they are able to break 8 rounds of PRINTCipher-48 with only 2 known plaintexts and 9 rounds under some additional assumptions. They show that it is possible to break the full 48-round...

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  • White Papers // May 2011

    Secure Single Sign-On and Web Authentication

    Single sign-on solutions allow users to sign on only once and have their identities automatically verified by each application or service they want to access. There are few practical and secure single sign-on models, even though it is of great importance to current distributed application environments. The authors introduce the...

    Provided By International Association for Cryptologic Research

  • White Papers // Nov 2012

    Towards Fully Collusion-Resistant ID-Based Establishment of Pairwise Keys

    Usually a communication link is secured by means of a symmetric-key algorithm. For that, a method is required to securely establish a symmetric-key for that algorithm. This old key establishment problem is still relevant and of paramount importance both in existing computer networks and new large-scale ubiquitous systems comprising resource-constrained...

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  • White Papers // Jan 2013

    Faster Index Calculus for the Medium Prime Case Application to 1175-Bit and 1425-Bit Finite Fields

    Many index calculus algorithms generate multiplicative relations between smoothness basis elements by using a process called Sieving. This process allows filtering potential candidate relations very quickly, without spending too much time to consider bad candidates. However, from an asymptotic point of view, there is not much difference between sieving and...

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  • White Papers // Dec 2012

    An Ideal Multi-Secret Sharing Scheme Based on Minimal Privileged Coalitions

    How to construct an ideal multi-secret sharing scheme for general access structures is difficult. In this paper, the authors solve an open problem proposed by Spiez et al. recently, namely to design an algorithm of privileged coalitions of any length if such coalitions exist. Furthermore, in terms of privileged coalitions,...

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  • White Papers // Dec 2012

    Cryptanalysis of Matrix Conjugation Schemes

    The conjugacy search problem plays a special role in group-based cryptography. Most of the cryptosystems based on groups use one or another variation of that problem. For instance: employs conjugacy search problem in braid groups, employ simultaneous conjugacy search problem in braid groups, employs twisted conjugacy problem, employ decomposition problem...

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  • White Papers // Dec 2011

    Design of Secure Image Transmission in MANET Using Number Theory Based Image Compression and Quasigroup Encryption (NTICQE) Algorithm

    Image compression and image encryption are pivotal to proper storage and transmission of images over MANET. Simultaneous image compression and encryption aims at achieving enhanced bandwidth utilization and security at the same time. The Number Theory based Image Compression and Quasigroup Encryption (NTICQE) algorithm employs number theoretic paradigm - Chinese...

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  • White Papers // May 2012

    Compilation Techniques for Efficient Encrypted Computation

    Fully Homomorphic Encryption (FHE) techniques are capable of performing encrypted computation on Boolean circuits, i.e., the user specifies encrypted inputs to the program, and the server computes on the encrypted inputs. Applying these techniques to general programs with recursive procedures and data-dependent loops has not been a focus of attention....

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  • White Papers // May 2012

    Transposition of AES Key Schedule

    In this paper, the authors point out a new weakness of the AES key schedule by revisiting an old observation exploited by many known attacks. They also discover a major cause for this weakness is that the column-by-column word-wise property in the key schedule matches nicely with the MixColumns operation...

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  • White Papers // Jun 2012

    Full Proof Cryptography: Verifiable Compilation of Efficient Zero-Knowledge Protocols

    Developers building cryptography into security-sensitive applications face a daunting task. Not only must they understand the security guarantees delivered by the constructions they choose, they must also implement and combine them correctly and efficiently. Cryptographic compilers free developers from having to implement cryptography on their own by turning high-level specifications...

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  • White Papers // Jun 2012

    Ring-LWE in Polynomial Rings

    Since its recent introduction, the Ring-LWE problem [LPR10] has already been used as a building block for numerous cryptographic applications. In addition to its original functionality as the basis of efficient lattice-based cryptosystems [LPR10], it has since been used as a hardness assumption in the constructions of efficient signature schemes...

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  • White Papers // Apr 2012

    Physical Unclonable Functions in Cryptographic Protocols: Security Proofs and Impossibility Results

    The authors investigate the power of Physical Unclonable Functions (PUFs) as a new primitive in cryptographic protocols. Their contributions split into three parts; they focus on the realizability of PUF-protocols in a special type of stand-alone setting (the "Stand-alone, good PUF setting") under minimal assumptions, they formally prove that there...

    Provided By International Association for Cryptologic Research

  • White Papers // Apr 2012

    Differentially Private Continual Monitoring of Heavy Hitters from Distributed Streams

    The authors consider applications scenarios where an untrusted aggregator wishes to continually monitor the heavy-hitters across a set of distributed streams. Since each stream can contain sensitive data, such as the purchase history of customers, they wish to guarantee the privacy of each stream, while allowing the untrusted aggregator to...

    Provided By International Association for Cryptologic Research

  • White Papers // Aug 2012

    Perfect Algebraic Immune Functions

    The study of the cryptanalysis of the filter and combination generators of stream ciphers based on Linear Feedback Shift Registers (LFSRs) has resulted in a wealth of cryptographic criteria for Boolean functions, such as balancedness, high algebraic degree, high nonlinearity, high correlation immunity and so on. An overview of cryptographic...

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  • White Papers // Apr 2012

    Strongly Secure Authenticated Key Exchange from Factoring, Codes, and Lattices

    Establishing secure channels is one of the most important areas of cryptographic research. Secure channels provide secrecy and authenticity for both communication parties. When parties can share secret information via a public communication channel, secure channels would be constructed on (symmetric key) encryptions and message authentication codes with the shared...

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  • White Papers // Mar 2012

    A Secret Sharing Scheme Based on Group Presentations and the Word Problem

    A (t, n)-threshold secret sharing scheme is a method to distribute a secret among n participants in such a way that any t participants can recover the secret, but no t - 1 participants can. In this paper, the authors propose two secret sharing schemes using non-abelian groups; the special...

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  • White Papers // Aug 2012

    Compress Multiple Ciphertexts Using Elgamal Encryption Schemes

    ElGamal encryption is one of fundamental public-key cryptosystems. One of its main advantages is that it is simple and efficient, but also that its chosen-plaintext security is clearly understood. Security overhead in terms of bandwidth, however, often becomes obstacles against its publicly wide use. In this paper, the authors deal...

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  • White Papers // Apr 2012

    Zero-Knowledge for Multivariate Polynomials

    The first Zero-Knowledge schemes were based on the factorization problem (for example Fischer-Micali-Racko in 1984, or Fiat-Shamir in 1986) or the Graph Isomorphism Problem. However the factorization problem is not expected to be a NP complete problem (since it is in NP and Co NP) and it has sub-exponential algorithms...

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  • White Papers // May 2012

    Ring Group Signatures

    In many applications of group signatures, not only a signer's identity but also which group the signer belongs to is sensitive information regarding signer privacy. In this paper, the authors study these applications and combine a group signature with a ring signature to create a ring group signature, which specifies...

    Provided By International Association for Cryptologic Research

  • White Papers // May 2012

    Cyptanalysis CDHP, BDHP and Tate Pairing Under Certain Conditions the Tate Pairing is Less Secure Than Weil

    This paper fall within the cadre of Cryptanalysis. Because, under certain condition, the authors would give a fairly simple method to solve the CDHP (the Problem Computational of Diffie and Hellman) and others problems associated to it. Since, solving this problem, will help them to provide a solution to the...

    Provided By International Association for Cryptologic Research

  • White Papers // Jun 2012

    A Way Reduce Signed Bitwise Differences That Transformed Into Same Modular Differences

    The authors study signed bitwise differences and modular differences. They find a way to reduce signed bitwise differences that can be transformed into same modular differences. In this way, it needs arithmetic difference. They establish one-one relationship between modular differences and arithmetic difference. And establish one-one relationship between signed bitwise...

    Provided By International Association for Cryptologic Research

  • White Papers // Jun 2012

    3D Hardware Canaries

    3D integration is a promising advanced manufacturing process offering a variety of new hardware security protection opportunities. This paper presents a way of securing 3D ICs using Hamiltonian paths as hardware integrity verification sensors. As 3D integration consists in the stacking of many metal layers, one can consider surrounding a...

    Provided By International Association for Cryptologic Research

  • White Papers // Jun 2012

    The Discrete Logarithm Problem in Non-Representable Rings

    For Discrete Logarithm based cryptography, it is desirable to find efficiently implementable groups for which sub-exponential algorithms for the Discrete Logarithm Problem are not available. Thus far, the only candidates for such groups seem to be (carefully chosen) groups of points on elliptic curves. Groups of invertible matrices over a...

    Provided By International Association for Cryptologic Research

  • White Papers // Jun 2012

    Generation of Nonlinear Feedback Shift Registers with Special-Purpose Hardware

    The NonLinear Feedback Shift Registers (NLFSR) are used to construct pseudorandom generators for stream ciphers. Their theory is not so complete as that of the Linear Feedback Shift Registers (LFSR). In general, it is not known how to construct NLFSRs with maximum period. The direct method is to search for...

    Provided By International Association for Cryptologic Research

  • White Papers // Sep 2012

    Fast and Compact Elliptic-Curve Cryptography

    Elliptic curve signatures have many advantages, however. Current attacks against elliptic curves scale exponentially with key size. Therefore ECC key and signatures can be considerably smaller than their RSA counterparts, and key generation and signing are much faster. Still, elliptic curve signatures' historically slow verification has kept these signatures out...

    Provided By International Association for Cryptologic Research

  • White Papers // May 2012

    On Instance Separation in the UC-Framework

    The UC approach of Canetti offers the advantage of stand-alone analysis while keeping security guaranties for arbitrary complex environment. When the authors implement by this approach, first they have to ensure secure instance separation and based on this condition, they are allowed to carry out a stand-alone analysis. In this...

    Provided By International Association for Cryptologic Research

  • White Papers // May 2012

    Anonymous Credentials Light

    The authors define and propose an efficient and provably secure construction of blind signatures with attributes. Prior notions of blind signatures did not yield themselves to the construction of anonymous credential systems, not even if they drop the unlinkability requirement of anonymous credentials. Their new notion in contrast is a...

    Provided By International Association for Cryptologic Research

  • White Papers // May 2012

    Broadcast-Enhanced Key Predistribution Schemes

    The authors present a formalization of a category of schemes which they call Broadcast-enhanced Key Predistribution Schemes. These schemes can be used instead of a key predistribution scheme in any network which has access to a trusted base station and broadcast channel. In such networks, Broadcast-enhanced Key Predistribution Schemes can...

    Provided By International Association for Cryptologic Research

  • White Papers // Jul 2012

    Two Grumpy Giants and a Baby

    Pollard's rho algorithm, along with parallelized, vectorized, and negating variants, is the standard method to compute discrete logarithms in generic prime-order groups. This paper presents two reasons that Pollard's rho algorithm is farther from optimality than generally believed; "Higher-Degree Local Anti-Collisions" make the rho walk less random than the predictions...

    Provided By International Association for Cryptologic Research

  • White Papers // Jun 2012

    RSA Modulus Generation in the Two-Party Case

    In this paper, secure two-party protocols are provided in order to securely generate a random k-bit RSA modulus n keeping its factorization secret. The authors show that most existing two-party protocols based on Boneh's test are not correct: an RSA modulus can be output in the malicious case. Recently, Hazay...

    Provided By International Association for Cryptologic Research

  • White Papers // Oct 2012

    Improved Side Channel Attack on the Block Cipher NOEKEON

    Classical cryptanalysis generally considers adversaries getting black box access to the cryptographic primitives they target, e.g. the inputs and outputs of a block cipher. However, considering the practical implementations of a block cipher, especially in resource limited systems such as smart cards, there is a stronger attack model, namely the...

    Provided By International Association for Cryptologic Research

  • White Papers // Aug 2012

    Approaches for the Parallelization of Software Implementation of Integer Multiplication

    In this paper, there are considered several approaches for the increasing performance of software implementation of integer multiplication algorithm for the 32-bit & 64-bit platforms via parallelization. The main idea of algorithm parallelization consists in delayed carry mechanism using which authors have proposed earlier. The delayed carry allows to get...

    Provided By International Association for Cryptologic Research

  • White Papers // Sep 2012

    Some Connections Between Primitive Roots and Quadratic Non-Residues Modulo a Prime

    Generating primitive roots modulo a prime is a fundamental problem in number theory, with major applications in cryptography. Diffie-Hellman key establishment scheme, ElGamal public-key cryptosystem, Schnorr identification scheme and Digital Signature Scheme are only a few examples which rely on generating primitive roots or elements of a certain order. Finding...

    Provided By International Association for Cryptologic Research

  • White Papers // Nov 2012

    Differential Analysis of the LED Block Cipher

    In this paper, the authors present a security analysis of the lightweight block cipher LED proposed by Guo et al. at CHES 2011. Since the design of LED is very similar to the Even-Mansour scheme, they first review existing attacks on this scheme and extend them to related-key and related-key-cipher...

    Provided By International Association for Cryptologic Research