Technische Universitat Darmstadt

Displaying 1-40 of 66 results

  • White Papers // Aug 2012

    Privacy-by-Design Based on Quantitative Threat Modeling

    While the general concept of "Privacy-by-Design (PbD)" is increasingly a popular one, there is considerable paucity of either rigorous or quantitative underpinnings supporting PbD. Drawing upon privacy-aware modeling techniques, this paper proposes a Quantitative Threat Modeling Methodology (QTMM) that can be used to draw objective conclusions about different privacy-related attacks...

    Provided By Technische Universitat Darmstadt

  • White Papers // Jul 2012

    Brief Announcement: MP-State: State-Aware Software Model Checking of Message-Passing Systems

    Software model checking is a useful and practical branch of verification for verifying the implementation of the system. The wide usability comes at a price of low time and space efficiency. In fact, model checking of even simple single-process programs can take several hours using state-of-the-art techniques. Verification complexity gets...

    Provided By Technische Universitat Darmstadt

  • White Papers // May 2012

    Quantitative Assessment of Cloud Security Level Agreements: A Case Study

    The users of Cloud Service Providers (CSP) often motivate their choice of providers based on criteria such as the offered Service Level Agreements (SLA) and costs, and also recently based on security aspects (i.e., due to regulatory compliance). Unfortunately, it is quite uncommon for a CSP to specify the security...

    Provided By Technische Universitat Darmstadt

  • White Papers // Apr 2012

    A Multivariate Based Threshold Ring Signature Scheme

    In this paper, the authors extend this scheme to a threshold ring identification and signature scheme. Their scheme is the first multivariate scheme of this type and generally the first multivariate signature scheme with special properties. Despite the fact that they need more rounds to achieve given levels of security,...

    Provided By Technische Universitat Darmstadt

  • White Papers // Apr 2012

    Improved Algebraic Side-Channel Attack on AES

    In this paper, the authors present improvements of the algebraic side-channel analysis of the Advanced Encryption Standard (AES) proposed. In particular, they optimize the algebraic representation of AES and the algebraic representation of the obtained side-channel information in order to speed up the attack and increase the success rate. They...

    Provided By Technische Universitat Darmstadt

  • White Papers // Apr 2012

    Key Updates for RFID Distance-Bounding Protocols: Achieving Narrow-Destructive Privacy

    Distance-bounding protocols address Man-In-The-Middle (MITM) in authentication protocols: by measuring response times, verifiers ensure that the responses are not purely relayed. Durholz et al. formalize the following attacks against distance-bounding protocols: mafia fraud, where adversaries must authenticate to the verifier in the presence of honest provers; terrorist fraud, where malicious...

    Provided By Technische Universitat Darmstadt

  • White Papers // Mar 2012

    Multi-Objective Aware Extraction of Task-Level Parallelism Using Genetic Algorithms

    A large amount of research work has been done in the area of automatic parallelization for decades, resulting in a huge amount of tools, which should relieve the designer from the burden of manually parallelizing an application. Unfortunately, most of these tools are only optimizing the execution time by splitting...

    Provided By Technische Universitat Darmstadt

  • White Papers // Feb 2012

    Study of the Invariant Coset Attack on PRINTcipher: More Weak Keys With Practical Key Recovery

    Lightweight cryptography gained its importance due to emergence of many applications that involve using small and resource constraint devices like RFID tags, smart cards, and sensors. Conventional cryptographic algorithms turned out to be too massive to be implemented on such devices. Therefore the need for new cryptographic primitives arose in...

    Provided By Technische Universitat Darmstadt

  • White Papers // Feb 2012

    Optimizing Model-Based Software Product Line Testing With Graph Transformations

    Software Product Lines (SPLs) are increasing in relevance and importance as various domains strive to cope with the challenges of supporting a high degree of variability in modern software systems. Especially the systematic testing of SPLs is nontrivial as a high degree of variability implies a vast number of possible...

    Provided By Technische Universitat Darmstadt

  • White Papers // Jan 2012

    TRCCIT: Tunable Reliability With Congestion Control for Information Transport in Wireless Sensor Networks

    A core functionality of Wireless Sensor Networks (WSNs) is to transport information from the network to the application/user. The evolvable application reliability requirements and the fluctuating perturbations lead to continuous deviation between the attained and desired reliability. Using an existing approach that guarantees a highest reliability is not appropriate for...

    Provided By Technische Universitat Darmstadt

  • White Papers // Dec 2011

    Timing Attacks Against the Syndrome Inversion in Code-Based Cryptosystems

    In this paper, the authors present new timing vulnerabilities that arise in the inversion of the error syndrome through the Extended Euclidean Algorithm that is part of the decryption operation of code-based Cryptosystems. They analyze three types of timing attack vulnerabilities theoretically and experimentally: the first allows recovery of the...

    Provided By Technische Universitat Darmstadt

  • White Papers // Dec 2011

    Fast and Secure Root-Finding for Code-Based Cryptosystems

    In this paper, the authors analyze four previously published respectively trivial approaches to the task of finding the roots of the error locator polynomial during the decryption operation of code-based encryption schemes. They compare the performance of these algorithms and show that optimizations concerning finite field element representations play a...

    Provided By Technische Universitat Darmstadt

  • White Papers // Oct 2011

    A RESTful Approach to Service Level Agreements for Cloud Environments

    Cloud Computing is becoming more and more a commodity service to all kinds of businesses. This leads to a stronger need for dependable service guarantees on the resources or applications offered to the customer by the provider via Service Level Agreements. Most offerings on the market, however, rely on non-electronic...

    Provided By Technische Universitat Darmstadt

  • White Papers // Sep 2011

    Towards a Comparative Performance Evaluation of Overlays for Networked Virtual Environments

    Peer-to-peer overlays for Networked Virtual Environments have recently gained much research interest, resulting in a variety of different approaches for spatial information dissemination. Although designed for the same purpose, the evaluation methodologies used by particular authors differ widely. This makes any comparison of existing systems difficult, if not impossible. To...

    Provided By Technische Universitat Darmstadt

  • White Papers // Jun 2011

    FIT for SOA? Introducing the F.I.T.-Metric to Optimize the Availability of Service Oriented Architectures

    The paradigm of Service-Oriented Architectures (SOA) is by now accepted for application integration and in widespread use. As an underlying key-technology of cloud computing and because of unresolved issues during operation and maintenance it remains a hot topic. SOA encapsulates business functionality in services, combining aspects from both the business...

    Provided By Technische Universitat Darmstadt

  • White Papers // Jun 2011

    Twin Clouds: Secure Cloud Computing With Low Latency

    Cloud computing promises a cost effective enabling technology to outsource storage and massively parallel computations. However, existing approaches for provably secure outsourcing of data and arbitrary computations are either based on tamper-proof hardware or fully homomorphic encryption. The former approaches are not scalable, while the latter ones are currently not...

    Provided By Technische Universitat Darmstadt

  • White Papers // May 2011

    Hiding the Policy in Cryptographic Access Control

    Recently, cryptographic access control has received a lot of attention, mainly due to the availability of efficient Attribute-Based Encryption (ABE) schemes. ABE allows to get rid of a trusted reference monitor by enforcing access rules in a cryptographic way. However, ABE has a privacy problem: the access policies are sent...

    Provided By Technische Universitat Darmstadt

  • White Papers // May 2011

    To Crash or Not to Crash: Efficient Modeling of Fail-Stop Faults

    A commonly used approach in practical verification is to verify a simplified model of the system rather than the system itself, which would entail infeasible verification complexity. This paper introduces a model for efficient model checking of message-passing systems with crash faults. The key to the achieved efficiency is the...

    Provided By Technische Universitat Darmstadt

  • White Papers // Apr 2011

    TOM: Topology Oriented Maintenance in Sparse Wireless Sensor Networks

    The physical number of sensor nodes constitutes a major cost factor for Wireless Sensor Networks (WSN) deployments. Hence, a natural goal is to minimize the number of sensor nodes to be deployed, while still maintaining the desired properties of the WSN. However, sparse networks even while connected, usually suffer from...

    Provided By Technische Universitat Darmstadt

  • White Papers // Apr 2011

    On the Security of the Winternitz One-Time Signature Scheme

    The authors show that the Winternitz one-time signature scheme is existentially unforgeable under adaptive chosen message attacks when instantiated with a family of pseudo random functions. Compared to previous results, which require a collision resistant hash function, the result provides significantly smaller signatures at the same security level. They also...

    Provided By Technische Universitat Darmstadt

  • White Papers // Apr 2011

    On the Design of Perturbation-Resilient Atomic Commit Protocols for Mobile Transactions

    Distributed mobile transactions utilize commit protocols to achieve atomicity and consistent decisions. This is challenging as mobile environments are typically characterized by frequent perturbations such as network disconnections and node failures. On one hand environmental constraints on mobile participants and wireless links may increase the resource blocking time of fixed...

    Provided By Technische Universitat Darmstadt

  • White Papers // Mar 2011

    Cryptographic Treatment of Private User Profiles

    The publication of private data in user profiles in a both secure and private way is a rising problem and of special interest in, e.g., online social networks that become more and more popular. Current approaches, especially for decentralized networks, often do not address this issue or impose large storage...

    Provided By Technische Universitat Darmstadt

  • White Papers // Feb 2011

    Twin Clouds: An Architecture for Secure Cloud Computing

    Cloud computing promises a more cost effective enabling technology to outsource storage and computations. Existing approaches for secure outsourcing of data and arbitrary computations are either based on a single tamper-proof hardware, or based on recently proposed fully homomorphic encryption. The hardware based solutions are not scaleable, and fully homomorphic...

    Provided By Technische Universitat Darmstadt

  • White Papers // Dec 2010

    Practical Affiliation-Hiding Authentication From Improved Polynomial Interpolation

    Among the plethora of privacy-friendly authentication techniques, Affiliation-Hiding (AH) protocols are valuable for their ability to hide not only identities of communicating users behind their affiliations (memberships to groups), but also these affiliations from non-members. These qualities become increasingly important in the highly computerized user-centric information society, where privacy is...

    Provided By Technische Universitat Darmstadt

  • White Papers // Dec 2010

    Conservative Application-Level Performance Analysis Through Simulation of MPSoCs

    Applications, often with real-time requirements, are mapped onto Multi-Processor Systems on Chip (MPSoCs). Hard real-time applications require no deadline misses, and a formal modelling approach must be used to analyze the worst-case performance, which is complicated and time consuming. Such models are restricted to specific application behaviors and not generally...

    Provided By Technische Universitat Darmstadt

  • White Papers // Dec 2010

    Towards a Common Interface for Overlay Network Simulators

    Simulation has become an important evaluation method in the area of Peer-To-Peer (P2P) research due to the scalability limitations of evaluation testbeds such as PlanetLab or G-Lab. Current simulators provide various abstraction levels for different underlay models, such that applications can be evaluated at different granularity. However, existing simulators suffer...

    Provided By Technische Universitat Darmstadt

  • White Papers // Nov 2010

    Better Key Sizes (and Attacks) for LWE-Based Encryption

    The authors analyze the concrete security and key sizes of theoretically sound lattice-based encryption schemes based on the "Learning With Errors" (LWE) problem. The main contributions are: A new lattice attack on LWE that combines basis reduction with an enumeration algorithm admitting a time/success tradeoff, which performs better than the...

    Provided By Technische Universitat Darmstadt

  • White Papers // Oct 2010

    A Security Architecture for Accessing Health Records on Mobile Phones

    Using mobile phones to access healthcare data is an upcoming application scenario of increasing importance in the near future. However, important aspects to consider in this context are the high security and privacy requirements for sensitive medical data. Current mobile phones using standard operating systems and software cannot offer appropriate...

    Provided By Technische Universitat Darmstadt

  • White Papers // Oct 2010

    Performance Evaluation of Multi Machine Virtual Environments

    Virtualization is already a common technology used in data centers as well as on desktop computers; it gains additional momentum with the spread of cloud computing. In this paper, the authors analyze the performance and behavior of virtual resources in multi virtual machine scenarios running the same workload. They evaluate...

    Provided By Technische Universitat Darmstadt

  • White Papers // Oct 2010

    Page Size Selection for OLTP Databases on SSD Storage

    Flash SSDs are a technology that has the potential of changing the database architecture and principles. The authors re-evaluate present trend of growing database page sizes considering its validity for SSD-based database storage. Their major findings are: on Flash storage this trend is reverted and best OLTP performance can be...

    Provided By Technische Universitat Darmstadt

  • White Papers // Oct 2010

    A Logistics Workload for Event Notification Middleware

    The event-based paradigm plays an important role to reflect logistics processes in modern IT infrastructures. Events occur at many stages, e.g., when goods tagged with RFID chips are scanned, when transportation vehicles move or when sensors report environmental observations. These events have to be delivered to interested consumers by a...

    Provided By Technische Universitat Darmstadt

  • White Papers // Sep 2010

    Exception Handling in Web Service Processes

    Cross-company business processes are common in today's networked economy and are nowadays often supported by process support systems that integrate the information systems of the different partners based on web service technology. In contrast to earlier Workflow Management Systems, which were often deployed in the controlled environment of a single...

    Provided By Technische Universitat Darmstadt

  • White Papers // Sep 2010

    How to Implement the Public Key Operations in Code-Based Cryptography on Memory-Constrained Devices

    While it is generally believed that due to their large public key sizes code based public key schemes cannot be conveniently used when memory-constrained devices are involved, the authors propose an approach for Public Key Infrastructure (PKI) scenarios which totally eliminates the need to store public keys of communication partners....

    Provided By Technische Universitat Darmstadt

  • White Papers // Aug 2010

    A Semantic World Model for Urban Search and Rescue Based on Heterogeneous Sensors

    In urban search and rescue scenarios, typical applications of robots include autonomous exploration of possibly dangerous sites, and the recognition of victims and other objects of interest. In complex scenarios, relying on only one type of sensor is often misleading, while using complementary sensors frequently helps improving the performance. To...

    Provided By Technische Universitat Darmstadt

  • White Papers // Aug 2010

    Selecting Parameters for the Rainbow Signature Scheme - Extended Version -

    Multivariate public key cryptography is one of the main approaches to guarantee the security of communication in a post-quantum world. One of the most promising candidates in this area is the Rainbow signature scheme, which was first proposed by J. Ding and D. Schmidt in 2005. In this paper the...

    Provided By Technische Universitat Darmstadt

  • White Papers // Aug 2010

    Building Large Storage Based On Flash Disks

    Flash SSDs are a technology that has the potential of drastically changing the architecture of a DBMS. In this paper, the authors examine the properties of a storage space built on SSDs with RAID and how these affect data intensive systems. While they observed the expected performance improvements of one...

    Provided By Technische Universitat Darmstadt

  • White Papers // Aug 2010

    Acdmcp: An Adaptive and Completely Distributed Multi-Hop Clustering Protocol for Wireless Sensor Networks

    Clustering is a very popular network structuring technique which mainly addresses the issue of scalability in large scale Wireless Sensor Networks. Additionally, it has been shown to improve the energy efficiency and prolong the life of the network. The suggested protocols mostly base their clustering criteria on some grouping attribute(s)...

    Provided By Technische Universitat Darmstadt

  • White Papers // Jul 2010

    Towards Provable Security of the Unbalanced Oil and Vinegar Signature Scheme Under Direct Attacks

    In this paper the authors show that solving systems coming from the public key of the Unbalanced Oil and Vinegar (UOV) signature scheme is on average at least as hard as solving a certain quadratic system with completely random quadratic part. In providing lower bounds on direct attack complexity they...

    Provided By Technische Universitat Darmstadt

  • White Papers // Jul 2010

    Security and Compliance in Clouds

    The use of cloud computing services is an attractive opportunity for companies to improve IT services and to achieve almost unlimited scalability of the IT infrastructure, and all of this at a significantly reduced cost than this is possible with internal resources. However, the use of a cloud service requires...

    Provided By Technische Universitat Darmstadt

  • White Papers // Jul 2010

    Map-Based Support for Wireless Sensor Network Simulation

    Wireless Sensor Networks (WSN) is receiving growing attention in the research community. As simulation is a frequently used approach also to test and validate approaches, the simulation environments need to be able to support the evolving WSN design schemes. While a growing research trend in WSN is to address regions...

    Provided By Technische Universitat Darmstadt

  • White Papers // May 2012

    Quantitative Assessment of Cloud Security Level Agreements: A Case Study

    The users of Cloud Service Providers (CSP) often motivate their choice of providers based on criteria such as the offered Service Level Agreements (SLA) and costs, and also recently based on security aspects (i.e., due to regulatory compliance). Unfortunately, it is quite uncommon for a CSP to specify the security...

    Provided By Technische Universitat Darmstadt

  • White Papers // Jul 2012

    Brief Announcement: MP-State: State-Aware Software Model Checking of Message-Passing Systems

    Software model checking is a useful and practical branch of verification for verifying the implementation of the system. The wide usability comes at a price of low time and space efficiency. In fact, model checking of even simple single-process programs can take several hours using state-of-the-art techniques. Verification complexity gets...

    Provided By Technische Universitat Darmstadt

  • White Papers // Aug 2012

    Privacy-by-Design Based on Quantitative Threat Modeling

    While the general concept of "Privacy-by-Design (PbD)" is increasingly a popular one, there is considerable paucity of either rigorous or quantitative underpinnings supporting PbD. Drawing upon privacy-aware modeling techniques, this paper proposes a Quantitative Threat Modeling Methodology (QTMM) that can be used to draw objective conclusions about different privacy-related attacks...

    Provided By Technische Universitat Darmstadt

  • White Papers // May 2009

    An Optimization Based Design for Integrated Dependable Real-Time Embedded Systems

    Moving from the traditional federated design paradigm, integration of mixed-criticality software components onto common computing platforms is increasingly being adopted by automotive, avionics and the control industry. This method faces new challenges such as the integration of varied functionalities (dependability, responsiveness, power consumption, etc.) under platform resource constraints and the...

    Provided By Technische Universitat Darmstadt

  • White Papers // Jul 2009

    Profiling the Operational Behavior of OS Device Drivers

    As the complexity of modern Operating Systems (OS) increases, testing key OS components such as Device Drivers (DD) becomes increasingly complex given the multitude of possible DD interactions. Currently, DD testing entails a broad spectrum of techniques, where static (requiring source code) and dynamic (requiring the executable image) and static-dynamic...

    Provided By Technische Universitat Darmstadt

  • White Papers // May 2011

    To Crash or Not to Crash: Efficient Modeling of Fail-Stop Faults

    A commonly used approach in practical verification is to verify a simplified model of the system rather than the system itself, which would entail infeasible verification complexity. This paper introduces a model for efficient model checking of message-passing systems with crash faults. The key to the achieved efficiency is the...

    Provided By Technische Universitat Darmstadt

  • White Papers // Apr 2010

    On Efficient Models for Model Checking Message-Passing Distributed Protocols

    The complexity of distributed algorithms, such as state machine replication, motivates the use of formal methods to assist correctness verification. The design of the formal model of an algorithm directly affects the efficiency of the analysis. Therefore, it is desirable that this model does not add "Unnecessary" complexity to the...

    Provided By Technische Universitat Darmstadt

  • White Papers // Mar 2010

    LEHP: Localized Energy Hole Profiling in Wireless Sensor Networks

    Wireless Sensor Networks (WSN) invariably display non-uniform energy usage distribution. This is mainly induced by the sink centric traffic or by non-uniform distribution of sensing activities and manifests as energy holes throughout the WSN. Holes can threaten the availability of the WSN by network partitioning and sensing voids. They are...

    Provided By Technische Universitat Darmstadt

  • White Papers // Mar 2010

    Data-Based Agreement for Inter-Vehicle Coordination

    Data-based agreement is increasingly used to implement traceable coordination across mobile entities such as ad hoc networked (autonomous) vehicles. In the authors' paper, they focus on data-based agreement using database transactions where mobile entities agree on a set of coordinated tasks that need to be performed by them in an...

    Provided By Technische Universitat Darmstadt

  • White Papers // Mar 2010

    Reordering for Better Compressibility: Efficient Spatial Sampling in Wireless Sensor Networks

    Compressed Sensing (CS) is a novel sampling paradigm that tries to take data-compression concepts down to the sampling layer of a sensory system. It states that discrete compressible signals are recoverable from sub-sampled data, when the data vector is acquired by a special linear transform of the original discrete signal...

    Provided By Technische Universitat Darmstadt

  • White Papers // Jan 2012

    TRCCIT: Tunable Reliability With Congestion Control for Information Transport in Wireless Sensor Networks

    A core functionality of Wireless Sensor Networks (WSNs) is to transport information from the network to the application/user. The evolvable application reliability requirements and the fluctuating perturbations lead to continuous deviation between the attained and desired reliability. Using an existing approach that guarantees a highest reliability is not appropriate for...

    Provided By Technische Universitat Darmstadt

  • White Papers // Sep 2009

    Role-Based Symmetry Reduction of Fault-Tolerant Distributed Protocols With Language Support

    Fault-Tolerant (FT) distributed protocols (such as group membership, consensus, etc.) represent fundamental building blocks for many practical systems, e.g., the Google File System. Not only does one desire rigor in the protocol design but especially in its verification given the complexity and fallibility of manual proofs. The application of Model...

    Provided By Technische Universitat Darmstadt

  • White Papers // Jun 2009

    Map-Based Modeling and Design of Wireless Sensor Networks With OMNeT++

    Wireless Sensor Networks (WSN) are receiving growing attention in the research community. As simulation is a frequently used approach to test and validate approaches, simulation environments need to be able to support the various WSN design schemes. Though the research trend in WSN is to address regions instead of single...

    Provided By Technische Universitat Darmstadt

  • White Papers // Jan 2009

    On Equivalence Partitioning of Code Paths Inside OS Kernel Components

    Commercial-Off-The-Shelf Operating Systems (COTS OSs) are increasingly chosen as key building blocks in embedded system design due to their rich feature-set available at low costs. Unfortunately, as the complexity of such OSs increases, testing key OS components such as Device Drivers (DD) to ensure continuous service provision becomes increasingly challenging....

    Provided By Technische Universitat Darmstadt

  • White Papers // Mar 2012

    Multi-Objective Aware Extraction of Task-Level Parallelism Using Genetic Algorithms

    A large amount of research work has been done in the area of automatic parallelization for decades, resulting in a huge amount of tools, which should relieve the designer from the burden of manually parallelizing an application. Unfortunately, most of these tools are only optimizing the execution time by splitting...

    Provided By Technische Universitat Darmstadt

  • White Papers // Sep 2010

    Exception Handling in Web Service Processes

    Cross-company business processes are common in today's networked economy and are nowadays often supported by process support systems that integrate the information systems of the different partners based on web service technology. In contrast to earlier Workflow Management Systems, which were often deployed in the controlled environment of a single...

    Provided By Technische Universitat Darmstadt

  • White Papers // Jul 2010

    Security and Compliance in Clouds

    The use of cloud computing services is an attractive opportunity for companies to improve IT services and to achieve almost unlimited scalability of the IT infrastructure, and all of this at a significantly reduced cost than this is possible with internal resources. However, the use of a cloud service requires...

    Provided By Technische Universitat Darmstadt

  • White Papers // Apr 2009

    PSP: Private and Secure Payment With RFID

    RFID can be used for a variety of applications, e.g., to conveniently pay for public transportation. However, achieving security and privacy of payment is challenging due to the extreme resource restrictions of RFID tags. This paper proposes PSP - a secure, RFID-based protocol for privacy-preserving payment. Similar to traditional electronic...

    Provided By Technische Universitat Darmstadt

  • White Papers // Aug 2009

    Wireless Sensor Networks and the Internet of Things: Selected Challenges

    Wireless Sensor Networks (WSNs) are increasingly gaining impact in one's day to day lives. They are finding a wide range of applications in various domains, including health-care, assisted and enhanced-living scenarios, industrial and production monitoring, control networks, and many other fields. In future, WSNs are expected to be integrated into...

    Provided By Technische Universitat Darmstadt

  • White Papers // Nov 2009

    Design and Implementation of a Cryptographic Plugin for E-Mail Clients

    Most applications that use cryptography implement and use only a limited set of cryptographic algorithms. In addition it is not easy to update these applications and extend their provided set of algorithms. This paper concentrates on e-mail clients and discusses a cryptographic plugin with focus on Mozilla Thunderbird. The paper...

    Provided By Technische Universitat Darmstadt

  • White Papers // Sep 2009

    Authoring Environment for Story-Based Digital Educational Games

    In this paper, the StoryTec authoring system, developed in the context of the European research project 80Days, is presented as an authoring tool enabling users without programming experience to create Digital Educational Games (DEG) or stories and to integrate content into them. The paper provides an overview of related software...

    Provided By Technische Universitat Darmstadt

  • White Papers // Jun 2009

    Application of a Similarity Measure for Graphs to Web-Based Document Structures

    Due to the tremendous amount of information provided by the World Wide Web (WWW) developing methods for mining the structure of web-based documents is of considerable interest. In this paper the authors present a similarity measure for graphs representing web-based hypertext structures. The similarity measure is mainly based on a...

    Provided By Technische Universitat Darmstadt

  • White Papers // Aug 2010

    Acdmcp: An Adaptive and Completely Distributed Multi-Hop Clustering Protocol for Wireless Sensor Networks

    Clustering is a very popular network structuring technique which mainly addresses the issue of scalability in large scale Wireless Sensor Networks. Additionally, it has been shown to improve the energy efficiency and prolong the life of the network. The suggested protocols mostly base their clustering criteria on some grouping attribute(s)...

    Provided By Technische Universitat Darmstadt

  • White Papers // Apr 2011

    On the Security of the Winternitz One-Time Signature Scheme

    The authors show that the Winternitz one-time signature scheme is existentially unforgeable under adaptive chosen message attacks when instantiated with a family of pseudo random functions. Compared to previous results, which require a collision resistant hash function, the result provides significantly smaller signatures at the same security level. They also...

    Provided By Technische Universitat Darmstadt

  • White Papers // Mar 2011

    Cryptographic Treatment of Private User Profiles

    The publication of private data in user profiles in a both secure and private way is a rising problem and of special interest in, e.g., online social networks that become more and more popular. Current approaches, especially for decentralized networks, often do not address this issue or impose large storage...

    Provided By Technische Universitat Darmstadt

  • White Papers // Dec 2010

    Practical Affiliation-Hiding Authentication From Improved Polynomial Interpolation

    Among the plethora of privacy-friendly authentication techniques, Affiliation-Hiding (AH) protocols are valuable for their ability to hide not only identities of communicating users behind their affiliations (memberships to groups), but also these affiliations from non-members. These qualities become increasingly important in the highly computerized user-centric information society, where privacy is...

    Provided By Technische Universitat Darmstadt

  • White Papers // Nov 2010

    Better Key Sizes (and Attacks) for LWE-Based Encryption

    The authors analyze the concrete security and key sizes of theoretically sound lattice-based encryption schemes based on the "Learning With Errors" (LWE) problem. The main contributions are: A new lattice attack on LWE that combines basis reduction with an enumeration algorithm admitting a time/success tradeoff, which performs better than the...

    Provided By Technische Universitat Darmstadt

  • White Papers // Sep 2010

    How to Implement the Public Key Operations in Code-Based Cryptography on Memory-Constrained Devices

    While it is generally believed that due to their large public key sizes code based public key schemes cannot be conveniently used when memory-constrained devices are involved, the authors propose an approach for Public Key Infrastructure (PKI) scenarios which totally eliminates the need to store public keys of communication partners....

    Provided By Technische Universitat Darmstadt

  • White Papers // Aug 2010

    Selecting Parameters for the Rainbow Signature Scheme - Extended Version -

    Multivariate public key cryptography is one of the main approaches to guarantee the security of communication in a post-quantum world. One of the most promising candidates in this area is the Rainbow signature scheme, which was first proposed by J. Ding and D. Schmidt in 2005. In this paper the...

    Provided By Technische Universitat Darmstadt

  • White Papers // Jul 2010

    Towards Provable Security of the Unbalanced Oil and Vinegar Signature Scheme Under Direct Attacks

    In this paper the authors show that solving systems coming from the public key of the Unbalanced Oil and Vinegar (UOV) signature scheme is on average at least as hard as solving a certain quadratic system with completely random quadratic part. In providing lower bounds on direct attack complexity they...

    Provided By Technische Universitat Darmstadt

  • White Papers // Dec 2009

    Security Analysis of the PACE Key-Agreement Protocol

    The authors analyze the Password Authenticated Connection Establishment (PACE) protocol for authenticated key agreement, recently proposed by the German Federal Office for Information Security (BSI) for the deployment in machine readable travel documents. They show that the PACE protocol is secure in the real-or-random sense of Abdalla, Fouque and Pointcheval,...

    Provided By Technische Universitat Darmstadt

  • White Papers // Sep 2009

    A Multivariate Signature Scheme With an Almost Cyclic Public Key

    Multivariate public key cryptography is one of the main approaches to guarantee the security of communication in a post quantum world. One of the major drawbacks in this area is the huge size of the public key. In this paper the authors present a new idea to create a multivariate...

    Provided By Technische Universitat Darmstadt

  • White Papers // Mar 2009

    Pipelined Control-Path Effects on Area and Performance of a Wormhole-Switched Network-on-Chip

    This paper presents design trade-off and performance impacts of the amount of pipeline phase of control path signals in a wormhole-switched Network-on-Chip (NoC). The numbers of the pipeline phase of the control path vary between two- and one-cycle pipeline phase. The control paths consist of the routing request paths for...

    Provided By Technische Universitat Darmstadt

  • White Papers // May 2011

    Hiding the Policy in Cryptographic Access Control

    Recently, cryptographic access control has received a lot of attention, mainly due to the availability of efficient Attribute-Based Encryption (ABE) schemes. ABE allows to get rid of a trusted reference monitor by enforcing access rules in a cryptographic way. However, ABE has a privacy problem: the access policies are sent...

    Provided By Technische Universitat Darmstadt

  • White Papers // Jul 2008

    Delay-Aware Mobile Transactions

    In the expanding e-society, mobile embedded systems are increasingly used to support transactions such as for banking, stock or database applications. Such systems entail a range of heterogeneous entities - both the embedded devices and the networks connecting them. While these systems are exposed to frequent and varied perturbations, the...

    Provided By Technische Universitat Darmstadt

  • White Papers // Apr 2009

    AReIT: Adaptive Reliable Information Transport Protocol for Wireless Sensor Networks

    The reliable delivery of services in service oriented architectures often entails the underlying basis of having well structured system and communication network models. With the rapid proliferation of ad-hoc mode of communication, such as Wireless Sensor Networks (WSNs), the reliable delivery of services increasingly encounters new communication and also network...

    Provided By Technische Universitat Darmstadt

  • White Papers // Jun 2011

    Twin Clouds: Secure Cloud Computing With Low Latency

    Cloud computing promises a cost effective enabling technology to outsource storage and massively parallel computations. However, existing approaches for provably secure outsourcing of data and arbitrary computations are either based on tamper-proof hardware or fully homomorphic encryption. The former approaches are not scalable, while the latter ones are currently not...

    Provided By Technische Universitat Darmstadt

  • White Papers // Oct 2010

    A Security Architecture for Accessing Health Records on Mobile Phones

    Using mobile phones to access healthcare data is an upcoming application scenario of increasing importance in the near future. However, important aspects to consider in this context are the high security and privacy requirements for sensitive medical data. Current mobile phones using standard operating systems and software cannot offer appropriate...

    Provided By Technische Universitat Darmstadt

  • White Papers // Jul 2010

    Map-Based Support for Wireless Sensor Network Simulation

    Wireless Sensor Networks (WSN) is receiving growing attention in the research community. As simulation is a frequently used approach also to test and validate approaches, the simulation environments need to be able to support the evolving WSN design schemes. While a growing research trend in WSN is to address regions...

    Provided By Technische Universitat Darmstadt

  • White Papers // Apr 2011

    On the Design of Perturbation-Resilient Atomic Commit Protocols for Mobile Transactions

    Distributed mobile transactions utilize commit protocols to achieve atomicity and consistent decisions. This is challenging as mobile environments are typically characterized by frequent perturbations such as network disconnections and node failures. On one hand environmental constraints on mobile participants and wireless links may increase the resource blocking time of fixed...

    Provided By Technische Universitat Darmstadt