University of Hagen

Displaying 1-18 of 18 results

  • White Papers // Dec 2013

    Fast Prime Field Elliptic Curve Cryptography with 256 Bit Primes

    In this paper the authors study software optimization of elliptic curve cryptography with 256-bit prime fields. The authors propose a constant-time implementation of the NIST and SECG standardized curve P-256, that can be seamlessly integrated into OpenSSL. This accelerates perfect forward secrecy TLS handshakes that use ECDSA and/or ECDHE, and...

    Provided By University of Hagen

  • White Papers // Nov 2013

    Fast Software Implementation of Binary Elliptic Curve Cryptography

    In this paper the authors present an efficient and side channel protected software implementation of point multiplication for the standard NIST and SECG binary elliptic curves. The enhanced performance is achieved by improving the Lopez-Dahab/Montgomery method at the algorithmic level, and by leveraging Intel's AVX architecture and the pclmulqdq processor...

    Provided By University of Hagen

  • White Papers // Oct 2013

    A Practical Related-Key Boomerang Attack for the Full MMB Block Cipher

    The MMB block cipher (Modular Multiplication-based Block cipher) is an iterative block cipher designed by the researchers in 1993 as an improvement of the PES and IPES ciphers. In this paper the authors present several new related-key differential characteristics of MMB. These characteristics can be used to form several related-key...

    Provided By University of Hagen

  • White Papers // Oct 2013

    Improved Linear Sieving Techniques with Applications to Step-Reduced LED-64

    In this paper, the authors describe new techniques in meet-in-the-middle attacks. Their basic technique is called a linear key sieve since it exploits as filtering conditions linear dependencies between key bits that are guessed from both sides of the attack. This should be contrasted with related previous attacks, which only...

    Provided By University of Hagen

  • White Papers // Aug 2013

    Sketch-Based Geometric Monitoring of Distributed Stream Queries

    Emerging large-scale monitoring applications rely on continuous tracking of complex data-analysis queries over collections of massive, physically-distributed data streams. Thus, in addition to the space- and time-efficiency requirements of conventional stream processing (at each remote monitor site), effective solutions also need to guarantee communication efficiency (over the underlying communication network)....

    Provided By University of Hagen

  • White Papers // Dec 2012

    Local Thresholding in General Network Graphs

    Local thresholding algorithms were first presented more than a decade ago and have since been applied to a variety of data mining tasks in peer-to-peer systems, wireless sensor networks, and in grid systems. One critical assumption made by those algorithms has always been cycle-free routing. The existence of even one...

    Provided By University of Hagen

  • White Papers // Oct 2012

    Self-Dierential Cryptanalysis of Up to 5 Rounds of SHA-3

    On October 2-nd 2012 NIST announced its selection of the Keccak scheme as the new SHA-3 hash standard. In this paper, the authors present the first published collision finding attacks on reduced-round versions of Keccak-384 and Keccak-512, providing actual collisions for 3-round versions, and describing attacks which are much faster...

    Provided By University of Hagen

  • White Papers // Jul 2012

    Simultaneous Hashing of Multiple Messages

    The performance of hash functions is important in various situations and platforms. One example is a server workload: authenticated encryption in SSL/TLS sessions, where hash functions are used for authentication, in HMAC mode. This is one reason why the performance of SHA-256 on modern x86-64 architectures was defined as a...

    Provided By University of Hagen

  • White Papers // Jul 2012

    Healthcare Process Support: Achievements, Challenges, Current Research

    Healthcare organizations are facing the challenge of delivering high-quality services to their patients at affordable costs. To tackle this challenge, the Medical Informatics community targets at formalisms for developing Decision-Support Systems (DSSs) based on clinical guidelines. At the same time, Business Process Management (BPM) enables IT supports for healthcare processes,...

    Provided By University of Hagen

  • White Papers // Apr 2012

    Efficient Dissection of Composite Problems, with Applications to Cryptanalysis, Knapsacks, and Combinatorial Search Problems

    A composite problem is a problem that can be split into several simpler subproblems which can be solved independently of each other. To prevent attacks based on such decompositions, designers of cryptographic schemes usually try to entangle the various parts of the scheme by using a complex key schedule in...

    Provided By University of Hagen

  • White Papers // May 2010

    Oblivious RAM

    In this paper the authors re-investigate the oblivious RAM concept introduced by the researchers, which enables a client that can store locally only a constant amount of data, to store remotely n data items, and access them while hiding the identities of the items which are being accessed. Oblivious RAM...

    Provided By University of Hagen

  • White Papers // Mar 2010

    A Formal Model for Process Context Learning

    Process models are considered to be a major asset in modern business organizations. They are expected to apply to all the possible business contexts in which the process may be executed, however not all of these are known a priori. Instead of identifying all contexts before the process is established,...

    Provided By University of Hagen

  • White Papers // Jul 2009

    Organizational Reference Models: Supporting an Adequate Design of Local Business Processes

    Reference models, whose aim is to capture domain knowledge, can assist in the adequate design of enterprise specific business processes. In complex organizations, business processes can be locally designed by specific organizational units. However, in order to be adequate, these processes should meet the local needs while maintaining the organizational...

    Provided By University of Hagen

  • White Papers // Jun 2009

    Motivations and Challenges for Digital Preservation in Design and Engineering

    Digital preservation is a fairly new consideration in design and engineering companies. The core motivations for enterprises to engage in digital preservation endeavors are of economic and legal nature. This paper provides an overview of software components and processes in typical engineering scenarios, based on electrical engineering as an example....

    Provided By University of Hagen

  • White Papers // May 2009

    Intel's New AES Instructions for Enhanced Performance and Security

    The Advanced Encryption Standard (AES) is the Federal Information Processing Standard for symmetric encryption. It is widely believed to be secure and efficient, and is therefore broadly accepted as the standard for both government and industry applications. If fact, almost any new protocol requiring symmetric encryption supports AES, and many...

    Provided By University of Hagen

  • White Papers // Oct 2008

    A Domain Engineering Approach for Situational Method Engineering

    Methodologies are one of the most significant key factors to the success of project development. Since there is no single methodology that can be uniquely pointed as \"The best\", the discipline of Situational Method Engineering (SME) promotes the idea of creating method components, rather than complete methodologies, and tailoring them...

    Provided By University of Hagen

  • White Papers // May 2008

    A Goal-Based Approach for Business Process Learning

    The authors establish a business process learning model as part of a process lifecycle management approach. They define business process learning as the mechanism which provides the ability to perform a specific process better with time, based upon the experience acquired while executing the process, which is reflected through the...

    Provided By University of Hagen

  • White Papers // Jul 2007

    Business Process Flexibility in Virtual Organizations

    Virtual organizations are perceived as a means for achieving flexibility. However, shared inter-organizational business processes may pose additional constraints on the internal processes of an organization and reduce their flexibility. The paper builds on a conceptual model of business processes in a virtual organization. The model aims at identifying a...

    Provided By University of Hagen

  • White Papers // Oct 2012

    Self-Dierential Cryptanalysis of Up to 5 Rounds of SHA-3

    On October 2-nd 2012 NIST announced its selection of the Keccak scheme as the new SHA-3 hash standard. In this paper, the authors present the first published collision finding attacks on reduced-round versions of Keccak-384 and Keccak-512, providing actual collisions for 3-round versions, and describing attacks which are much faster...

    Provided By University of Hagen

  • White Papers // Jul 2012

    Simultaneous Hashing of Multiple Messages

    The performance of hash functions is important in various situations and platforms. One example is a server workload: authenticated encryption in SSL/TLS sessions, where hash functions are used for authentication, in HMAC mode. This is one reason why the performance of SHA-256 on modern x86-64 architectures was defined as a...

    Provided By University of Hagen

  • White Papers // Dec 2012

    Local Thresholding in General Network Graphs

    Local thresholding algorithms were first presented more than a decade ago and have since been applied to a variety of data mining tasks in peer-to-peer systems, wireless sensor networks, and in grid systems. One critical assumption made by those algorithms has always been cycle-free routing. The existence of even one...

    Provided By University of Hagen

  • White Papers // Apr 2012

    Efficient Dissection of Composite Problems, with Applications to Cryptanalysis, Knapsacks, and Combinatorial Search Problems

    A composite problem is a problem that can be split into several simpler subproblems which can be solved independently of each other. To prevent attacks based on such decompositions, designers of cryptographic schemes usually try to entangle the various parts of the scheme by using a complex key schedule in...

    Provided By University of Hagen

  • White Papers // Jun 2009

    Motivations and Challenges for Digital Preservation in Design and Engineering

    Digital preservation is a fairly new consideration in design and engineering companies. The core motivations for enterprises to engage in digital preservation endeavors are of economic and legal nature. This paper provides an overview of software components and processes in typical engineering scenarios, based on electrical engineering as an example....

    Provided By University of Hagen

  • White Papers // Jul 2012

    Healthcare Process Support: Achievements, Challenges, Current Research

    Healthcare organizations are facing the challenge of delivering high-quality services to their patients at affordable costs. To tackle this challenge, the Medical Informatics community targets at formalisms for developing Decision-Support Systems (DSSs) based on clinical guidelines. At the same time, Business Process Management (BPM) enables IT supports for healthcare processes,...

    Provided By University of Hagen

  • White Papers // Aug 2013

    Sketch-Based Geometric Monitoring of Distributed Stream Queries

    Emerging large-scale monitoring applications rely on continuous tracking of complex data-analysis queries over collections of massive, physically-distributed data streams. Thus, in addition to the space- and time-efficiency requirements of conventional stream processing (at each remote monitor site), effective solutions also need to guarantee communication efficiency (over the underlying communication network)....

    Provided By University of Hagen

  • White Papers // Oct 2008

    A Domain Engineering Approach for Situational Method Engineering

    Methodologies are one of the most significant key factors to the success of project development. Since there is no single methodology that can be uniquely pointed as \"The best\", the discipline of Situational Method Engineering (SME) promotes the idea of creating method components, rather than complete methodologies, and tailoring them...

    Provided By University of Hagen

  • White Papers // May 2010

    Oblivious RAM

    In this paper the authors re-investigate the oblivious RAM concept introduced by the researchers, which enables a client that can store locally only a constant amount of data, to store remotely n data items, and access them while hiding the identities of the items which are being accessed. Oblivious RAM...

    Provided By University of Hagen

  • White Papers // May 2009

    Intel's New AES Instructions for Enhanced Performance and Security

    The Advanced Encryption Standard (AES) is the Federal Information Processing Standard for symmetric encryption. It is widely believed to be secure and efficient, and is therefore broadly accepted as the standard for both government and industry applications. If fact, almost any new protocol requiring symmetric encryption supports AES, and many...

    Provided By University of Hagen

  • White Papers // Oct 2013

    Improved Linear Sieving Techniques with Applications to Step-Reduced LED-64

    In this paper, the authors describe new techniques in meet-in-the-middle attacks. Their basic technique is called a linear key sieve since it exploits as filtering conditions linear dependencies between key bits that are guessed from both sides of the attack. This should be contrasted with related previous attacks, which only...

    Provided By University of Hagen

  • White Papers // Oct 2013

    A Practical Related-Key Boomerang Attack for the Full MMB Block Cipher

    The MMB block cipher (Modular Multiplication-based Block cipher) is an iterative block cipher designed by the researchers in 1993 as an improvement of the PES and IPES ciphers. In this paper the authors present several new related-key differential characteristics of MMB. These characteristics can be used to form several related-key...

    Provided By University of Hagen

  • White Papers // Nov 2013

    Fast Software Implementation of Binary Elliptic Curve Cryptography

    In this paper the authors present an efficient and side channel protected software implementation of point multiplication for the standard NIST and SECG binary elliptic curves. The enhanced performance is achieved by improving the Lopez-Dahab/Montgomery method at the algorithmic level, and by leveraging Intel's AVX architecture and the pclmulqdq processor...

    Provided By University of Hagen

  • White Papers // Dec 2013

    Fast Prime Field Elliptic Curve Cryptography with 256 Bit Primes

    In this paper the authors study software optimization of elliptic curve cryptography with 256-bit prime fields. The authors propose a constant-time implementation of the NIST and SECG standardized curve P-256, that can be seamlessly integrated into OpenSSL. This accelerates perfect forward secrecy TLS handshakes that use ECDSA and/or ECDHE, and...

    Provided By University of Hagen

  • White Papers // May 2008

    A Goal-Based Approach for Business Process Learning

    The authors establish a business process learning model as part of a process lifecycle management approach. They define business process learning as the mechanism which provides the ability to perform a specific process better with time, based upon the experience acquired while executing the process, which is reflected through the...

    Provided By University of Hagen

  • White Papers // Jul 2007

    Business Process Flexibility in Virtual Organizations

    Virtual organizations are perceived as a means for achieving flexibility. However, shared inter-organizational business processes may pose additional constraints on the internal processes of an organization and reduce their flexibility. The paper builds on a conceptual model of business processes in a virtual organization. The model aims at identifying a...

    Provided By University of Hagen

  • White Papers // Jul 2009

    Organizational Reference Models: Supporting an Adequate Design of Local Business Processes

    Reference models, whose aim is to capture domain knowledge, can assist in the adequate design of enterprise specific business processes. In complex organizations, business processes can be locally designed by specific organizational units. However, in order to be adequate, these processes should meet the local needs while maintaining the organizational...

    Provided By University of Hagen

  • White Papers // Mar 2010

    A Formal Model for Process Context Learning

    Process models are considered to be a major asset in modern business organizations. They are expected to apply to all the possible business contexts in which the process may be executed, however not all of these are known a priori. Instead of identifying all contexts before the process is established,...

    Provided By University of Hagen