University of Brighton

Displaying 1-40 of 53 results

  • White Papers // Feb 2014

    Efficient, Oblivious Data Structures for MPC

    The authors present oblivious implementations of several data structures for secure Multi-Party Computation (MPC) such as arrays, dictionaries, and priority queues. The resulting oblivious data structures have only poly-logarithmic overhead compared with their classical counterparts. To achieve this, they give secure multiparty protocols for the ORAM and the path ORAM...

    Provided By University of Brighton

  • White Papers // Jan 2014

    Improvements on an Authentication Scheme for Vehicular Sensor Networks

    In a recent paper, Shim (2012) presented a very interesting authentication scheme for vehicular sensor networks. Shim claimed that the scheme is secure against the highest adopted level of attack, namely the Chosen-IDentity and Chosen-Message Attack (CID-CMA). Nevertheless, the authors find that the proof in Shim's paper does not actually...

    Provided By University of Brighton

  • White Papers // Dec 2013

    Decentralized Traceable Attribute-Based Signatures

    Attribute-based signatures allow a signer owning a set of attributes to anonymously sign a message w.r.t. some signing policy. A recipient of the signature is convinced that a signer with a set of attributes satisfying the signing policy has indeed produced the signature without learning the identity of the signer...

    Provided By University of Brighton

  • White Papers // Dec 2013

    Safe Enclosures: Towards Cryptographic Techniques for Server Protection

    Cryptography is generally used to protect sensitive data from an untrusted server. In this paper, the authors investigate the converse question: can they use cryptography to protect a trusted server from untrusted data. As a first step in this direction, they propose the notion of safe enclosures. Intuitively, a safe...

    Provided By University of Brighton

  • White Papers // Dec 2013

    RKA-KDM Secure Encryption from Public-Key Encryption

    The authors construct Secret-Key Encryption (SKE) schemes that are secure against Related-Key Attacks and in the presence of Key-Dependent Messages (RKA-KDM secure). They emphasize that RKA-KDM security is not merely the conjunction of individual security properties, but covers attacks in which cipher-texts of key-dependent messages under related keys are available....

    Provided By University of Brighton

  • White Papers // Nov 2013

    An Analysis of the EMV Channel Establishment Protocol

    With over 1.6 billion debit and credit cards in use worldwide, the EMV system (a.k.a. \"Chip-and-PIN\") has become one of the most important deployed cryptographic protocol suites. Recently, the EMV consortium has decided to upgrade the existing RSA based system with a new system relying on Elliptic Curve Cryptography (ECC)....

    Provided By University of Brighton

  • White Papers // Oct 2013

    New Abstractions in Applied Pi-Calculus and Automated Verification of Protected Executions

    Protocols for the protected execution of programs, like those based on a hardware root of trust, will become of fundamental importance for computer security. In parallel to such protocols, there is therefore a need to develop models and tools that allow formal specification and automated verification of the desired security...

    Provided By University of Brighton

  • White Papers // Oct 2013

    An Architecture for Practical Actively Secure MPC with Dishonest Majority

    The authors present a runtime environment for executing secure programs via a multi-party computation protocol in the preprocessing model. The runtime environment is general and allows arbitrary reactive computations to be performed. A particularly novel aspect is that it automatically determines the minimum number of rounds needed for a computation,...

    Provided By University of Brighton

  • White Papers // Sep 2013

    Improved Security for a Ring-Based Fully Homomorphic Encryption Scheme

    In 1996, researchers introduced an efficient lattice based encryption scheme dubbed NTRUEncrypt. Unfortunately, this scheme lacks a proof of security. However, in 2011, other researchers showed how to modify NTRUEncrypt to reduce security to standard problems in ideal lattices. In 2012, they proposed a fully homomorphic scheme based on this...

    Provided By University of Brighton

  • White Papers // Sep 2013

    Estimating Key Sizes for High Dimensional Lattice Based Systems

    The authors revisit the estimation of parameters for use in applications of the BGV homomorphic encryption system, which generally require high dimensional lattices. In particular, they utilize the BKZ-2.0 simulator of chen and nguyen to identify the best lattice attack that can be mounted using BKZ in a given dimension...

    Provided By University of Brighton

  • White Papers // Sep 2013

    Sub-Linear Blind Ring Signatures without Random Oracles

    Ring signatures allow a signer to anonymously sign a message on behalf of a set of arbitrarily chosen signers called a \"Ring\". Blind signatures, on the other hand, allow a user to obtain a signature on a message while maintaining the privacy of the message. Blind ring signatures combine properties...

    Provided By University of Brighton

  • White Papers // Sep 2013

    KDM Security in the Hybrid Framework

    The authors study the natural question of how well suited the hybrid encryption paradigm is in the context of Key-Dependent Message (KDM) attacks. They prove that if a Key Derivation Function (KDF) is used in between the public (KEM) and symmetric (DEM) part of the hybrid scheme and this KDF...

    Provided By University of Brighton

  • White Papers // Sep 2013

    Dynamic Data Storage Estimation for Multiple Concurrent Applications Using Probability Distribution Modeling in WSNs

    Wireless Sensor Networks (WSN) have become a mainstream technology for environmental monitoring and observing various variables of interest over extended periods of time via large-scale networks of sensors. WSNs have a wide range of applications including wildfire detection, healthcare, military, and habitat monitoring. In all such application areas, gathering and...

    Provided By University of Brighton

  • White Papers // Aug 2013

    Cryptographically Enforced RBAC

    Cryptographic access control promises to offer easily distributed trust and broader applicability, while reducing reliance on low-level online monitors. Traditional implementations of cryptographic access control rely on simple cryptographic primitives whereas recent endeavors employ primitives with richer functionality and security guarantees. Worryingly, few of the existing cryptographic access-control schemes come...

    Provided By University of Brighton

  • White Papers // Jul 2013

    Light-Weight Primitive, Feather-Weight Security - A Cryptanalytic Knock-Out

    The ubiquity of modern information systems highlights the importance of all enabling technologies, and their ability to keep pace with the demands of associated applications. An archetypal example is that of Radio Frequency IDentification (RFID) tags, which interact with a reader (or terminal); such combinations form the basis for applications...

    Provided By University of Brighton

  • White Papers // May 2013

    A Comparison of Statistical Techniques for Detecting Side-Channel Information Leakage in Cryptographic Devices

    The evaluation of the resilience of cryptographic devices against side-channel adversaries is an issue of increasing importance. The development of a standardized testing methodology for side-channel resistance of crypto-graphic devices is an issue that has received recent focus from standardization bodies such as NIST. Statistical techniques such as hypothesis and...

    Provided By University of Brighton

  • White Papers // May 2013

    A Leakage Resilient MAC

    The authors put forward a Message Authentication Code (MAC) for which they claim a high degree of resilience against a key-recovering attacker expoiting practical side channels. They achieve this by blending the lessons learned from many years of engineering with the scientific approach provided by leakage resilience. This highlights how...

    Provided By University of Brighton

  • White Papers // Apr 2013

    Masking Tables - An Underestimated Security Risk

    The literature on side-channel analysis describes numerous masking schemes designed to protect block ciphers at the implementation level. Such masking schemes typically require the computation of masked tables prior to the execution of an encryption function. In this paper the authors revisit an attack which directly exploits this computation in...

    Provided By University of Brighton

  • White Papers // Feb 2013

    Experimental Demonstration of an OpenFlow Based Software-Defined Optical Network Employing Packet, Fixed and Flexible DWDM Grid Technologies on an International Multidomain Testbed

    Software Defined Networking (SDN) and flexible grid optical transport technology are two key technologies that allow network operators to customize their infrastructure based on application requirements and therefore minimizing the extra capital and operational costs required for hosting new applications. In this paper, for the first time the authors report...

    Provided By University of Brighton

  • White Papers // Oct 2012

    Security Analysis of an Open Car Immobilizer Protocol Stack

    An increasing number of embedded security applications-which traditionally have been heavily reliant on secret and/or proprietary solutions-apply the principle of open evaluation. A recent example is the specification of an open security protocol stack for car immobilizer applications by Atmel, which has been presented at ESCAR 2010. This stack is...

    Provided By University of Brighton

  • White Papers // Sep 2012

    Enhanced Chosen-Ciphertext Security and Applications

    The authors introduce and study a new notion of Enhanced Chosen-Ciphertext security (ECCA) for publickey encryption. Loosely speaking, in ECCA, when the decryption oracle returns a plaintext to the adversary, it also provides coins under which the returned plaintext encrypts to the queried ciphertext (when they exist). Their results mainly...

    Provided By University of Brighton

  • White Papers // Aug 2012

    The Low-Call Diet: Authenticated Encryption for Call Counting HSM Users

    The authors present a new mode of operation for obtaining authenticated encryption suited for use in banking and government environments where cryptographic services are only available via a Hardware Security Module (HSM) which protects the keys but offers a limited API. The practical problem is that despite the existence of...

    Provided By University of Brighton

  • White Papers // Aug 2012

    The Myth of Generic DPA... and the Magic of Learning

    A prominent strand within the side-channel literature is the quest for generic attack strategies: methods by which data-dependent leakage measurements can be successfully analyzed with 'No' a priori knowledge about the leakage characteristics. In this paper, the authors introduce a well-reasoned definition for what it means to have 'No' a...

    Provided By University of Brighton

  • White Papers // Aug 2012

    Efficient Signatures of Knowledge and DAA in the Standard Model

    Direct Anonymous Attestation (DAA) is one of the most complex cryptographic protocols deployed in practice. It allows an embedded secure processor known as a Trusted Platform Module (TPM) to attest to the configuration of its host computer without violating the owner's privacy. DAA has been standardized by the Trusted Computing...

    Provided By University of Brighton

  • White Papers // Aug 2012

    Differential Fault Analysis of AES: Towards Reaching its Limits

    In this paper, the authors present a theoretical analysis of the limits of the Differential Fault Analysis (DFA) of AES by developing an interrelationship between conventional cryptanalysis of AES and DFAs. They show that the existing attacks have not reached these limits and present techniques to reach these. More specifically,...

    Provided By University of Brighton

  • White Papers // Jun 2012

    On Reconfigurable Fabrics and Generic Side-Channel Countermeasures

    The use of field programmable devices in security-critical applications is growing in popularity; in part, this can be attributed to their potential for balancing metrics such as efficiency and algorithm agility. However, in common with non-programmable alternatives, physical attack techniques such as fault and power analysis are a threat. The...

    Provided By University of Brighton

  • White Papers // Jun 2012

    Compiler Assisted Masking

    Differential Power Analysis (DPA) attacks find a statistical correlation between the power consumption of a cryptographic device and intermediate values within the computation. Randomization via (Boolean) masking of intermediate values breaks this statistical dependence and thus prevents such attacks (at least up to a certain order). Especially for software implementations,...

    Provided By University of Brighton

  • White Papers // May 2012

    Efficient Threshold Zero-Knowledge with Applications to User-Centric Protocols

    In this paper, the authors investigate on threshold proofs, a framework for distributing the prover's side of interactive proofs of knowledge over multiple parties. Interactive Proofs of Knowledge (PoK) are widely used primitives of cryptographic protocols, including important user-centric protocols, such as identification schemes, electronic cash (e-cash), and anonymous credentials....

    Provided By University of Brighton

  • White Papers // May 2012

    Quantifying Side-Channel Information Leakage From Web Applications

    Recent research has shown that many popular web applications are vulnerable to side-channel attacks on encrypted streams of network data produced by the interaction of a user with an application. As a result, private user data is susceptible to being recovered by a side-channel adversary. A recent focus has been...

    Provided By University of Brighton

  • White Papers // May 2012

    Improved "Partial Sums"-Based Square Attack on AES

    The Square attack as a means of attacking reduced round variants of AES was described in the initial description of the Rijndael block cipher. This attack can be applied to AES, with a relatively small number of chosen plaintext-ciphertext pairs, reduced to less than six rounds in the case of...

    Provided By University of Brighton

  • White Papers // Apr 2012

    On Necessary and Sufficient Conditions for Private Ballot Submission

    The authors exhibit the precise security guarantees that a public key encryption scheme needs to satisfy to guarantee ballot privacy when used in a large class of voting systems. They also identify new security notions for public key encryption that characterize the number of times that a public key can...

    Provided By University of Brighton

  • White Papers // Mar 2012

    Plaintext-Checkable Encryption

    The authors study the problem of searching on encrypted data, where the search is performed using a plaintext message or a keyword, rather than a message-specific trapdoor as done by state-of-the-art schemes. The use cases include delegation of keyword search e.g. to a cloud data storage provider or to an...

    Provided By University of Brighton

  • White Papers // Oct 2011

    Constructive and Destructive Use of Compilers in Elliptic Curve Cryptography

    Although cryptographic software implementation is often performed by expert programmers, the range of performance and security driven options, as well as more mundane software engineering issues, still make it a challenge. The use of domain specific language and compiler techniques to assist in description and optimization of cryptographic software is...

    Provided By University of Brighton

  • White Papers // Feb 2011

    Commuting Signatures and Verifiable Encryption

    Verifiable encryption allows one to encrypt a signature while preserving its public verifiability. The authors introduce a new primitive called commuting sig-natures and verifiable encryption that extends this in multiple ways, such as enabling encryption of both signature and message while proving validity. More importantly, given a ciphertext, a signer...

    Provided By University of Brighton

  • White Papers // Sep 2010

    Motes in the Jungle: Lessons Learned From a Short-Term WSN Deployment in the Ecuador Cloud Forest

    The authors study the characteristics of the communication links of a wireless sensor network in a tropical cloud forest in Ecuador, in the context of a wildlife monitoring application. Thick vegetation and high humidity are in principle a challenge for the IEEE 802.15.4 radio they employed. They performed experiments with...

    Provided By University of Brighton

  • White Papers // Jun 2010

    Coordinate Blinding Over Large Prime Fields

    Side-channel analysis can be used to try and derive unknown information used in cryptographic algorithms, such as cryptographic keys. The first side-channel described in the literature was based on the total time taken to compute a cryptographic algorithm. Preventing this attack is well understood, as one just requires a regular...

    Provided By University of Brighton

  • White Papers // Jun 2010

    Side Channel Analysis of Cryptographic Software via Early-Terminating Multiplications

    The design of embedded processors demands a careful tradeoff between many conflicting objectives such as performance, silicon area and power consumption. Finding such a trade-off can often ignore the issue of security, which can cause, otherwise secure, software to leak information through so-called micro-architectural side channels. In this paper the...

    Provided By University of Brighton

  • White Papers // May 2010

    On the Efficiency of Classical and Quantum Oblivious Transfer Reductions

    Due to its universality Oblivious Transfer (OT) is a primitive of great importance in secure multi-party computation. OT is impossible to implement from scratch in an unconditionally secure way, but there are many reductions of OT to other variants of OT, as well as other primitives such as noisy channels....

    Provided By University of Brighton

  • White Papers // Mar 2010

    Groth-Sahai Proofs

    Since their introduction in 2008, the Non-Interactive Zero Knowledge (NIZK) and Non-Interactive Witness Indistinguishable (NIWI) proofs designed by Groth and Sahai have been used in numerous applications. In this paper, the authors offer two contributions to the study of these proof systems. They identify and correct some errors, present in...

    Provided By University of Brighton

  • White Papers // Jan 2010

    Improved Fault Analysis of Signature Schemes

    In this paper, the authors show that the fault attack described is much more efficient than originally claimed. They proved that, using the same attack model, they need 34.3% less faulty signatures to recover a 160-bit private key. Furthermore, by improving the fault model expression, they show that for some...

    Provided By University of Brighton

  • White Papers // Feb 2014

    Efficient, Oblivious Data Structures for MPC

    The authors present oblivious implementations of several data structures for secure Multi-Party Computation (MPC) such as arrays, dictionaries, and priority queues. The resulting oblivious data structures have only poly-logarithmic overhead compared with their classical counterparts. To achieve this, they give secure multiparty protocols for the ORAM and the path ORAM...

    Provided By University of Brighton

  • White Papers // Aug 2012

    The Low-Call Diet: Authenticated Encryption for Call Counting HSM Users

    The authors present a new mode of operation for obtaining authenticated encryption suited for use in banking and government environments where cryptographic services are only available via a Hardware Security Module (HSM) which protects the keys but offers a limited API. The practical problem is that despite the existence of...

    Provided By University of Brighton

  • White Papers // Aug 2012

    Efficient Signatures of Knowledge and DAA in the Standard Model

    Direct Anonymous Attestation (DAA) is one of the most complex cryptographic protocols deployed in practice. It allows an embedded secure processor known as a Trusted Platform Module (TPM) to attest to the configuration of its host computer without violating the owner's privacy. DAA has been standardized by the Trusted Computing...

    Provided By University of Brighton

  • White Papers // Aug 2012

    Differential Fault Analysis of AES: Towards Reaching its Limits

    In this paper, the authors present a theoretical analysis of the limits of the Differential Fault Analysis (DFA) of AES by developing an interrelationship between conventional cryptanalysis of AES and DFAs. They show that the existing attacks have not reached these limits and present techniques to reach these. More specifically,...

    Provided By University of Brighton

  • White Papers // Jul 2008

    Expanding Window Fountain Codes for Unequal Error Protection

    A novel approach to provide Unequal Error Protection (UEP) using rateless codes over erasure channels, named Expanding Window Fountain (EWF) codes, is developed and discussed. EWF codes use a windowing technique rather than a weighted (non-uniform) selection of input symbols to achieve UEP property. The windowing approach introduces additional parameters...

    Provided By University of Brighton

  • White Papers // Jul 2009

    Precoded EWF Codes for Unequal Error Protection of Scalable Video

    Rateless codes are Forward Error Correcting (FEC) codes of linear encoding-decoding complexity and asymptotically capacity-approaching performance over erasure channels with any erasure statistics. They have been recently recognized as a simple and efficient solution for packetized video transmission over networks with packet erasures. However, to adapt the error correcting capabilities...

    Provided By University of Brighton

  • White Papers // Jun 2012

    On Reconfigurable Fabrics and Generic Side-Channel Countermeasures

    The use of field programmable devices in security-critical applications is growing in popularity; in part, this can be attributed to their potential for balancing metrics such as efficiency and algorithm agility. However, in common with non-programmable alternatives, physical attack techniques such as fault and power analysis are a threat. The...

    Provided By University of Brighton

  • White Papers // May 2012

    Efficient Threshold Zero-Knowledge with Applications to User-Centric Protocols

    In this paper, the authors investigate on threshold proofs, a framework for distributing the prover's side of interactive proofs of knowledge over multiple parties. Interactive Proofs of Knowledge (PoK) are widely used primitives of cryptographic protocols, including important user-centric protocols, such as identification schemes, electronic cash (e-cash), and anonymous credentials....

    Provided By University of Brighton

  • White Papers // May 2012

    Improved "Partial Sums"-Based Square Attack on AES

    The Square attack as a means of attacking reduced round variants of AES was described in the initial description of the Rijndael block cipher. This attack can be applied to AES, with a relatively small number of chosen plaintext-ciphertext pairs, reduced to less than six rounds in the case of...

    Provided By University of Brighton

  • White Papers // May 2012

    Quantifying Side-Channel Information Leakage From Web Applications

    Recent research has shown that many popular web applications are vulnerable to side-channel attacks on encrypted streams of network data produced by the interaction of a user with an application. As a result, private user data is susceptible to being recovered by a side-channel adversary. A recent focus has been...

    Provided By University of Brighton

  • White Papers // Aug 2012

    The Myth of Generic DPA... and the Magic of Learning

    A prominent strand within the side-channel literature is the quest for generic attack strategies: methods by which data-dependent leakage measurements can be successfully analyzed with 'No' a priori knowledge about the leakage characteristics. In this paper, the authors introduce a well-reasoned definition for what it means to have 'No' a...

    Provided By University of Brighton

  • White Papers // Apr 2012

    On Necessary and Sufficient Conditions for Private Ballot Submission

    The authors exhibit the precise security guarantees that a public key encryption scheme needs to satisfy to guarantee ballot privacy when used in a large class of voting systems. They also identify new security notions for public key encryption that characterize the number of times that a public key can...

    Provided By University of Brighton

  • White Papers // Feb 2013

    Experimental Demonstration of an OpenFlow Based Software-Defined Optical Network Employing Packet, Fixed and Flexible DWDM Grid Technologies on an International Multidomain Testbed

    Software Defined Networking (SDN) and flexible grid optical transport technology are two key technologies that allow network operators to customize their infrastructure based on application requirements and therefore minimizing the extra capital and operational costs required for hosting new applications. In this paper, for the first time the authors report...

    Provided By University of Brighton

  • White Papers // Sep 2012

    Enhanced Chosen-Ciphertext Security and Applications

    The authors introduce and study a new notion of Enhanced Chosen-Ciphertext security (ECCA) for publickey encryption. Loosely speaking, in ECCA, when the decryption oracle returns a plaintext to the adversary, it also provides coins under which the returned plaintext encrypts to the queried ciphertext (when they exist). Their results mainly...

    Provided By University of Brighton

  • White Papers // May 2013

    A Comparison of Statistical Techniques for Detecting Side-Channel Information Leakage in Cryptographic Devices

    The evaluation of the resilience of cryptographic devices against side-channel adversaries is an issue of increasing importance. The development of a standardized testing methodology for side-channel resistance of crypto-graphic devices is an issue that has received recent focus from standardization bodies such as NIST. Statistical techniques such as hypothesis and...

    Provided By University of Brighton

  • White Papers // May 2013

    A Leakage Resilient MAC

    The authors put forward a Message Authentication Code (MAC) for which they claim a high degree of resilience against a key-recovering attacker expoiting practical side channels. They achieve this by blending the lessons learned from many years of engineering with the scientific approach provided by leakage resilience. This highlights how...

    Provided By University of Brighton

  • White Papers // Sep 2013

    Dynamic Data Storage Estimation for Multiple Concurrent Applications Using Probability Distribution Modeling in WSNs

    Wireless Sensor Networks (WSN) have become a mainstream technology for environmental monitoring and observing various variables of interest over extended periods of time via large-scale networks of sensors. WSNs have a wide range of applications including wildfire detection, healthcare, military, and habitat monitoring. In all such application areas, gathering and...

    Provided By University of Brighton

  • White Papers // Jun 2010

    Coordinate Blinding Over Large Prime Fields

    Side-channel analysis can be used to try and derive unknown information used in cryptographic algorithms, such as cryptographic keys. The first side-channel described in the literature was based on the total time taken to compute a cryptographic algorithm. Preventing this attack is well understood, as one just requires a regular...

    Provided By University of Brighton

  • White Papers // Jun 2010

    Side Channel Analysis of Cryptographic Software via Early-Terminating Multiplications

    The design of embedded processors demands a careful tradeoff between many conflicting objectives such as performance, silicon area and power consumption. Finding such a trade-off can often ignore the issue of security, which can cause, otherwise secure, software to leak information through so-called micro-architectural side channels. In this paper the...

    Provided By University of Brighton

  • White Papers // Jan 2010

    Improved Fault Analysis of Signature Schemes

    In this paper, the authors show that the fault attack described is much more efficient than originally claimed. They proved that, using the same attack model, they need 34.3% less faulty signatures to recover a 160-bit private key. Furthermore, by improving the fault model expression, they show that for some...

    Provided By University of Brighton

  • White Papers // Oct 2012

    Security Analysis of an Open Car Immobilizer Protocol Stack

    An increasing number of embedded security applications-which traditionally have been heavily reliant on secret and/or proprietary solutions-apply the principle of open evaluation. A recent example is the specification of an open security protocol stack for car immobilizer applications by Atmel, which has been presented at ESCAR 2010. This stack is...

    Provided By University of Brighton

  • White Papers // Jun 2012

    Compiler Assisted Masking

    Differential Power Analysis (DPA) attacks find a statistical correlation between the power consumption of a cryptographic device and intermediate values within the computation. Randomization via (Boolean) masking of intermediate values breaks this statistical dependence and thus prevents such attacks (at least up to a certain order). Especially for software implementations,...

    Provided By University of Brighton

  • White Papers // Jul 2007

    Power Attacks Resistance of Cryptographic S-Boxes with Added Error Detection Circuits

    Many side-channel attacks on implementations of cryptographic algorithms have been developed in recent years demonstrating the ease of extracting the secret key. In response, various schemes to protect cryptographic devices against such attacks have been devised and some implemented in practice. Almost all of these protection schemes target an individual...

    Provided By University of Brighton

  • White Papers // Oct 2009

    SPECI, a Simulation Tool Exploring Cloud-Scale Data Centres

    There is a rapid increase in the size of Data Centers (DCs) used to provide cloud computing services. It is commonly agreed that not all properties in the middleware that manages DCs will scale linearly with the number of components. Further, \"Normal failure\" complicates the assessment of the performance of...

    Provided By University of Brighton

  • White Papers // Mar 2012

    Plaintext-Checkable Encryption

    The authors study the problem of searching on encrypted data, where the search is performed using a plaintext message or a keyword, rather than a message-specific trapdoor as done by state-of-the-art schemes. The use cases include delegation of keyword search e.g. to a cloud data storage provider or to an...

    Provided By University of Brighton

  • White Papers // Oct 2011

    Constructive and Destructive Use of Compilers in Elliptic Curve Cryptography

    Although cryptographic software implementation is often performed by expert programmers, the range of performance and security driven options, as well as more mundane software engineering issues, still make it a challenge. The use of domain specific language and compiler techniques to assist in description and optimization of cryptographic software is...

    Provided By University of Brighton

  • White Papers // Aug 2008

    Light-Weight Instruction Set Extensions for Bit-Sliced Cryptography

    Bit-slicing is a non-conventional implementation technique for cryptographic software where an n-bit processor is considered as a collection of n 1-bit execution units operating in SIMD mode. Particularly when implementing symmetric ciphers, the bit-slicing approach has several advantages over more conventional alternatives: it often allows one to reduce memory footprint...

    Provided By University of Brighton

  • White Papers // May 2007

    Embedded Implementation of LASH

    With the security of standardized cryptographic hash functions in question, interest in new designs based on provably secure foundations has been reignited. LASH is a hash function design whose security is related to hard lattice problems. Although the tightness of the security reduction is dubious, LASH makes an interesting trade-off...

    Provided By University of Brighton

  • White Papers // Sep 2007

    A Security Framework for Data Distribution in Qualitative Analysis Tools: Digital Rights Management in MiMeG

    Qualitative data is now commonly collected, stored, collated and analyzed in digital formats, introducing new challenges for computer support. The burgeoning scale and complexity of digital data has meant that qualitative analysis tools are becoming increasingly popular options for managing and collaborating over social scientific data. One particularly important development...

    Provided By University of Brighton

  • White Papers // Sep 2007

    Efficient KEMs with Partial Message Recovery

    There are many important factors to consider when choosing a practical encryption scheme, including speed, provable security, code size, and bandwidth efficiency. Bandwidth efficiency is often only considered as an afterthought, but for many real world problems this can be as important as keeping the computational and implementational complexity low....

    Provided By University of Brighton

  • White Papers // May 2009

    A Grid Data Mining Architecture for Learning Classifier Systems

    Recently, there is a growing interest among the researchers and software developers in exploring Learning Classifier System (LCS) implemented in parallel and distributed grid structure for data mining, due to its practical applications. The paper highlights the some aspects of the LCS and studying the competitive data mining model with...

    Provided By University of Brighton

  • White Papers // Oct 2013

    An Architecture for Practical Actively Secure MPC with Dishonest Majority

    The authors present a runtime environment for executing secure programs via a multi-party computation protocol in the preprocessing model. The runtime environment is general and allows arbitrary reactive computations to be performed. A particularly novel aspect is that it automatically determines the minimum number of rounds needed for a computation,...

    Provided By University of Brighton

  • White Papers // Sep 2013

    Improved Security for a Ring-Based Fully Homomorphic Encryption Scheme

    In 1996, researchers introduced an efficient lattice based encryption scheme dubbed NTRUEncrypt. Unfortunately, this scheme lacks a proof of security. However, in 2011, other researchers showed how to modify NTRUEncrypt to reduce security to standard problems in ideal lattices. In 2012, they proposed a fully homomorphic scheme based on this...

    Provided By University of Brighton

  • White Papers // Nov 2013

    An Analysis of the EMV Channel Establishment Protocol

    With over 1.6 billion debit and credit cards in use worldwide, the EMV system (a.k.a. \"Chip-and-PIN\") has become one of the most important deployed cryptographic protocol suites. Recently, the EMV consortium has decided to upgrade the existing RSA based system with a new system relying on Elliptic Curve Cryptography (ECC)....

    Provided By University of Brighton

  • White Papers // Feb 2011

    Commuting Signatures and Verifiable Encryption

    Verifiable encryption allows one to encrypt a signature while preserving its public verifiability. The authors introduce a new primitive called commuting sig-natures and verifiable encryption that extends this in multiple ways, such as enabling encryption of both signature and message while proving validity. More importantly, given a ciphertext, a signer...

    Provided By University of Brighton

  • White Papers // Mar 2010

    Groth-Sahai Proofs

    Since their introduction in 2008, the Non-Interactive Zero Knowledge (NIZK) and Non-Interactive Witness Indistinguishable (NIWI) proofs designed by Groth and Sahai have been used in numerous applications. In this paper, the authors offer two contributions to the study of these proof systems. They identify and correct some errors, present in...

    Provided By University of Brighton

  • White Papers // May 2010

    On the Efficiency of Classical and Quantum Oblivious Transfer Reductions

    Due to its universality Oblivious Transfer (OT) is a primitive of great importance in secure multi-party computation. OT is impossible to implement from scratch in an unconditionally secure way, but there are many reductions of OT to other variants of OT, as well as other primitives such as noisy channels....

    Provided By University of Brighton

  • White Papers // Sep 2009

    Secure Two-Party Computation is Practical

    Secure multi-party computation has been considered by the cryptographic community for a number of years. Until recently it has been a purely theoretical area, with few implementations with which to test various ideas. This has led to a number of optimizations being proposed which are quite restricted in their application....

    Provided By University of Brighton

  • White Papers // Sep 2009

    Security Notions and Generic Constructions for Client Puzzles

    By a computational puzzle the authors mean a mildly difficult computational problem that requires resources (processor cycles, memory, or both) to solve. Puzzles have found a variety of uses in security. In this paper they are concerned with client puzzles: a type of puzzle used as a defense against Denial...

    Provided By University of Brighton

  • White Papers // Jan 2014

    Improvements on an Authentication Scheme for Vehicular Sensor Networks

    In a recent paper, Shim (2012) presented a very interesting authentication scheme for vehicular sensor networks. Shim claimed that the scheme is secure against the highest adopted level of attack, namely the Chosen-IDentity and Chosen-Message Attack (CID-CMA). Nevertheless, the authors find that the proof in Shim's paper does not actually...

    Provided By University of Brighton