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SaS Seminars

Software and Systems Research Seminar Series


The SaS Seminars are a permanent series of open seminars of the Division of Software and Systems (SaS) at the Department of Computer and Information Science (IDA), Linköping University. The objective of the seminars is to present outstanding research and ideas/problems relevant for SaS present and future activities. In particular, seminars cover the SaS research areas software engineering, programming environments, system software, embedded SW/HW systems, computer systems engineering, realtime systems, parallel and distributed computing, and theoretical computer science. - Two kinds of seminars are planned:

  • talks by invited speakers not affiliated with SaS,

  • internal seminars presenting lab research to whole SaS.

The speakers are expected to give a broad perspective of the presented research, adressing the audience with a general computer science background but possibly with no specific knowledge in the domain of the presented research. The normal length of a presentation is 60 minutes, including discussion.

The SaS seminars are coordinated by Ahmed Rezine.



Recent / Upcoming SaS Seminars (2019)



Determining Minimum Hash Width for Hash Chains

Prof. Dr. Jörg Keller, Fern Universität in Hagen, Germany.

Wednesday, May 22, 9:00, room John von Neumann.

Abstract:
Cryptographic hash functions are used in authentication, and repeated application in hash chains is used in communication protocols. In embedded devices, the width of hash values and the associated effort to evaluate the hash function is crucial, and hence the hash values should be as short as possible but should still be sufficient to guarantee the required level of security. We present a new proof for a known result by Flajolet and Odlyzko (Crypto 1989), using only elementary combinatoric and probabilistic arguments. Using this result, we derive a bound on the expected number of hash values still reachable after a given number of steps in the hash chain, so that given any two of the three parameters: hash chain length, width of the hash value, and security level, the remaining parameter can be computed. Furthermore, we illustrate how to ?refresh? a hash chain to increase the number of reachable hash values if the initial seed is long enough. Based on this, we present a scheme that allows reduced width of hash values, and thus reduced energy consumption in the device, for a hash chain of similar length and similar security level. We illustrate our findings with experiments.

Bio of speaker:
Jörg Keller is professor at the faculty for mathematics and computer science of Fern Universität in Hagen, Germany, where he holds the chair of Parallelism and VLSI. His research interests include Internet Security, Fault Tolerant Computing, VLSI Design and Parallel Computing.




Model-driven dependability forecasting of software systems

Prof. Simona Bernardi, University of Zaragoza, Spain.

Tuesday, March 5, 11:00, room John von Neumann.

Abstract:
In this talk I introduce the model-driven approach to the modelling and analysis of dependability of software systems in the early life-cycle, that considers three types of models:

    1) software models, used for architecture/design specification and represented with a general purpose software modelling language, that is Unified Modeling Language (UML);
    2) software models with "dependability annotations" obtained from software models by adding information related to dependability properties;
    3) formal models used for dependability analysis; such models have the advantage of being supported by existing analysis methods.
I will focus on Stochastic Petri Net models. The talk aims at giving an insight of the following aspects: the first is the dependability (meta-)modelling, that handles the transition from model of type (1) to model of type (2), the second is the model transformation that addresses the transition from model of type (2) to model of type (3), and the third is the evaluation of dependability properties with the analysis of Stochastic Petri Net models.

Bio of speaker:
Simona Bernardi is an Assistant Professor in the Department of Computer Science and Systems Engineering at the University of Zaragoza, Spain, from 2017. She received a M.S. degree in Mathematics and a Ph.D. degree in Computer Science, in 1997 and 2003, respectively, both from the University of Torino, Italy. In the past, she held a researcher position in the University of Torino, from 2004 to 2010, and a professor position at the Centro Universitario de la Defensa in the General Military Academy of Zaragoza from 2010 to 2017. She has been visiting researcher at the Carleton University (ON, Canada), the University of L'Aquila and the University "Federico II" of Naples, Italy. Her research interests are in the area of software engineering and process mining, in particular model-driven engineering, verification and validation of performance, dependability and survivability software requirements, and formal methods for the modelling and analysis of software systems. She is co-author of the book "Model-driven dependability assessment of software-systems", published by Springer.





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Last updated: 2019-04-26