Josef Widder
Privatdoz. Dipl.-Ing. Dr.techn.
Research Focus
- Logic and Computation: 50%
- Computer Engineering: 50%
Research Areas
- Proof-based System Engineering, Fault-tolerant systems, Formal verification, Dependable Systems, model checking, Real-time systems, Distributed Computing
Role
- Affiliated
Embedded Computing Systems, E191-02
Contact
- josef.darth.widder@tuwien.ac.at
- vCard from TISS
- ti.tuwien.ac.at/ecs/people/widder
- informatics.tuwien.ac.at/people/josef-widder
- tiss.tuwien.ac.at/person/52123
Courses
Projects
- 2011 – 2019 / Austrian Science Fund (FWF) / Publication
- 2011 – 2015 / Vienna Science and Technology Fund (WWTF) / Publications (2)
- 2004 – 2008 / European Commission / Website
- 2004 – 2008 / Austrian Science Fund (FWF) / Publication
Publications
2022
- Stoilkovska, I., Konnov, I., Widder, J., Zuleger, F. (2022). Verifying safety of synchronous fault-tolerant algorithms by bounded model checking. International Journal on Software Tools for Technology Transfer, 24(1), 33–48. Invited and peer-reviewed.
2021
- Stoilkovska, I., Konnov, I., Widder, J., Zuleger, F. (2021). Eliminating Message Counters in Synchronous Threshold Automata. In VMCAI 2021: Verification, Model Checking, and Abstract Interpretation (pp. 196–218). Springer LNCS. Peer-reviewed.
2020
- Stoilkovska, I., Konnov, I., Widder, J., Zuleger, F. (2020). Eliminating Message Counters in Threshold Automata. In Automated Technology for Verification and Analysis. 18th International Symposium, ATVA 2020, Hanoi, Vietnam, October 19-23, 2020, Proceedings (pp. 192–212). Springer. Peer-reviewed.DOI: 10.34726/423 / Download: PDF
- Konnov, I., Lazic, M., Stoilkovska, I., Widder, J. (2020). Tutorial: Parameterized Verification with Byzantine Model Checker. In Formal Techniques for Distributed Objects, Components, and Systems. 40th IFIP WG 6.1 International Conference, FORTE 2020, Held as Part of the 15th International Federated Conference on Distributed Computing Techniques, DisCoTec 2020, Valletta, Malta, June 15–19, 2020, Proceedings (pp. 189–207). Springer. Invited and peer-reviewed.DOI: 10.34726/422 / Download: PDF
2019
- Damian, A., Drăgoi, C., Militaru, A., Widder, J. (2019). Communication-Closed Asynchronous Protocols. In Computer Aided Verification : 31st International Conference, CAV 2019, New York City, NY, USA, July 15-18, 2019, Proceedings, Part II (pp. 344–363). Springer. Peer-reviewed.
- Bertrand, N., Konnov, I., Lazić, M., Widder, J. (2019). Verification of Randomized Consensus Algorithms Under Round-Rigid Adversaries. In W. Fokkink R. van Glabbeek (Eds.), 30th International Conference on Concurrency Theory (pp. 33:1-33:15). Schloss Dagstuhl - Leibniz-Zentrum fuer Informatik, Germany. Peer-reviewed.
- Stoilkovska, I., Konnov, I., Widder, J., Zuleger, F. (2019). Verifying Safety of Synchronous Fault-Tolerant Algorithms by Bounded Model Checking. In Tools and Algorithms for the Construction and Analysis of Systems : 25th International Conference, TACAS 2019, Held as Part of the European Joint Conferences on Theory and Practice of Software, ETAPS 2019, Prague, Czech Republic, April 6–11, 2019, Proceedings, Part II (pp. 357–374). Springer. Peer-reviewed.
2018
- Aminof, B., Rubin, S., Stoilkovska, I., Widder, J., Zuleger, F. (2018). Parameterized Model Checking of Synchronous Distributed Algorithms by Abstraction. In I. Dillig J. Palsberg (Eds.), Verification, Model Checking, and Abstract Interpretation : 19th International Conference, VMCAI 2018, Los Angeles, CA, USA, January 7-9, 2018, Proceedings. Cham. Peer-reviewed.DOI: 10.1007/978-3-319-73721-8_1 / Download: PDF
- Schmid, U., Widder, J. (Eds.). (2018). 32nd International Symposium on Distributed Computing : DISC 2018, October 15–19, New Orleans, Louisiana, USA. Dagstuhl Publishing LIPICS. Peer-reviewed.
- Konnov, I., Widder, J. (2018). ByMC: Byzantine Model Checker. In T. Margaria B. Steffen (Eds.), Leveraging Applications of Formal Methods, Verification and Validation. Distributed Systems. ISoLA 2018, Proceedings, Part III (pp. 327–342). Springer. Peer-reviewed.
- Dragoi, C., Lazić, M., Widder, J. (2018). Communication-Closed Layers as Paradigm for Distributed Systems: A Manifesto. In Proceedings of the International Scientific Conference - Sinteza 2018. Sinteza 2018 International Scientific Conference on Information Technology and Data Related Research, Belgrad, Serbia. Singidunum University.
- Kukovec, J., Konnov, I., Widder, J. (2018). Reachability in Parameterized Systems: All Flavors of Threshold Automata. In S. Schewe L. Zhang (Eds.), 29th International Conference on Concurrency Theory (CONCUR 2018) (pp. 19:1-19:17). Schloss Dagstuhl - Leibniz-Zentrum für Informatik GmbH, Dagstuhl Publishing. Peer-reviewed.
2017
- Konnov, I., Veith, H., Widder, J. (2017). On the completeness of bounded model checking for threshold-based distributed algorithms: Reachability. Information and Computation, 252, 95–109. Peer-reviewed.DOI: 10.1016/j.ic.2016.03.006 / Project:
- Konnov, I., Lazić, M., Veith, H., Widder, J. (2017). Para^2: Parameterized Path Reduction, Acceleration, and SMT for Reachability in Threshold-Guarded Distributed Algorithms. Formal Methods in System Design, 51(2), 270–307. Invited and peer-reviewed.DOI: 10.1007/s10703-017-0297-4 / Project:
- Konnov, I., Widder, J., Spegni, F., Spalazzi, L. (2017). Accuracy of Message Counting Abstraction in Fault-Tolerant Distributed Algorithms. In A. Bouajjani D. Monniaux (Eds.), Verification, Model Checking, and Abstract Interpretation : 18th International Conference, VMCAI 2017, Paris, France, January 15–17, 2017, Proceedings. Springer Heidelberg.DOI: 10.1007/978-3-319-52234-0_19 / Download: PDF
- Konnov, I., Lazić, M., Veith, H., Widder, J. (2017). A short counterexample property for safety and liveness verification of fault-tolerant distributed algorithms. In Proceedings of the 44th ACM SIGPLAN Symposium on Principles of Programming Languages. 44th ACM SIGPLAN Symposium on Principles of Programming Languages (POPL), Paris, France. ACM. Peer-reviewed.DOI: 10.1145/3009837.3009860 / Project:
- Lazić, M., Konnov, I., Widder, J., Bloem, R. (2017). Synthesis of Distributed Algorithms with Parameterized Threshold Guards. In J. Aspnes, A. Bessani, P. Felber, J. Leitao (Eds.), 21st International Conference on Principles of Distributed Systems (OPODIS 2017) (pp. 32:1-32:20). LIPIcs-Leibniz International Proceedings in Informatics. Peer-reviewed.DOI: 10.4230/LIPIcs.OPODIS.2017.32 / Project:
2016
- Bloem, R., Jacobs, S., Khalimov, A., Konnov, I., Rubin, S., Veith, H., Widder, J. (2016). Decidability of Parameterized Verification. ACM SIGACT News, 47(2), 53–64.DOI: 10.1145/2951860.2951873 / Project:
- Konnov, I., Veith, H., Widder, J. (2016). What You Always Wanted to Know About Model Checking of Fault-Tolerant Distributed Algorithms. In Perspectives of System Informatics : 10th International Andrei Ershov Informatics Conference, PSI 2015, in Memory of Helmut Veith, Kazan and Innopolis, Russia, August 24-27, 2015, Revised Selected Papers (pp. 6–21). Springer.DOI: 10.1007/978-3-319-41579-6_2 / Download: PDF
2015
- Charron-Bost, B., Függer, M., Welch, J. L., Widder, J. (2015). Time Complexity of Link Reversal Routing. ACM Transactions on Algorithms, 11(3), 1–39. Peer-reviewed.DOI: 10.1145/2644815
- Konnov, I., Veith, H., Widder, J. (2015). SMT and POR Beat Counter Abstraction: Parameterized Model Checking of Threshold-Based Distributed Algorithms. In Computer Aided Verification (pp. 85–102). LNCS Springer. Peer-reviewed.
- Bloem, R., Jacobs, S., Khalimov, A., Konnov, I., Rubin, S., Veith, H., Widder, J. (2015). Decidability of Parameterized Verification. In Synthesis Lectures on Distributed Computing Theory (p. 170). Morgan Claypool Publishers.
2014
- Gmeiner, A., Konnov, I., Schmid, U., Veith, H., Widder, J. (2014). Tutorial on Parameterized Model Checking of Fault-Tolerant Distributed Algorithms. In Formal Methods for Executable Software Models (pp. 122–171). Springer.
- Deutsch, T., Widder, J. (2014). Approaching Verification and Validation Challenges in Smart Grids. In Tagungsband ComForEn 2014 (p. 6). Eigenverlag des Österreich isch en Verbandes für Elektrotec h nik.HDL: 20.500.12708/55738
- Sastry, S., Widder, J. (2014). Solvability-Based Comparison of Failure Detectors. In 2014 IEEE 13th International Symposium on Network Computing and Applications. International Symposium on Network Computing and Applications (NCA), Boston, United States of America (the). IEEE Computer Society. Peer-reviewed.DOI: 10.1109/nca.2014.46
- Konnov, I., Veith, H., Widder, J. (2014). On the Completeness of Bounded Model Checking for Threshold-Based Distributed Algorithms: Reachability. In CONCUR 2014 – Concurrency Theory (pp. 125–140). Peer-reviewed.
- Drăgoi, C., Henzinger, T. A., Veith, H., Widder, J., Zufferey, D. (2014). A Logic-Based Framework for Verifying Consensus Algorithms. In Verification, Model Checking, and Abstract Interpretation 15th International Conference, VMCAI 2014, San Diego, CA, USA, January 19-21, 2014, Proceedings (pp. 161–181). Springer / LNCS. Peer-reviewed.
2013
- Charron-Bost, B., Gaillard, A., Welch, J. L., Widder, J. (2013). Link Reversal Routing with Binary Link Labels: Work Complexity. SIAM Journal on Computing, 42(2), 634–661. Peer-reviewed.DOI: 10.1137/110843095
- Charron-Bost, B., Merz, S., Rybalchenko, A., Widder, J. (2013). Formal Verification of Distributed Algorithms. Dagstuhl Reports, 3(4), 1–16.DOI: 10.4230/DagRep.3.4.1
- John, A., Konnov, I., Schmid, U., Veith, H., Widder, J. (2013). Towards Modeling and Model Checking Fault-Tolerant Distributed Algorithms. In Model Checking Software (pp. 209–226). LNCS, Springer. Peer-reviewed.
- John, A., Konnov, I., Schmid, U., Veith, H., Widder, J. (2013). Brief announcement: parameterized model checking of fault-tolerant distributed algorithms by abstraction. In Proceedings of the 2013 ACM symposium on Principles of distributed computing - PODC ’13. ACM SIGACT-SIGOPS Symposium on Principles of Distributed Computing (PODC), Montreal, Canada. ACM. Peer-reviewed.
- John, A., Konnov, I., Schmid, U., Veith, H., Widder, J. (2013). Parameterized model checking of fault-tolerant distributed algorithms by abstraction. In FMCAD (pp. 201–209). Peer-reviewed.HDL: 20.500.12708/54827
2012
- Widder, J., Biely, M., Gridling, G., Weiss, B., Blanquart, J.-P. (2012). Consensus in the presence of mortal Byzantine faulty processes. Distributed Computing, 24(6), 299–321. Peer-reviewed.
- Függer, M., Widder, J. (2012). Efficient Checking of Link-Reversal-Based Concurrent Systems. In CONCUR 2012- Concurrency Theory 23rd International Conference, CONCUR 2012, Newcastle upon Tyne, September 4-7, 2012. Proceedings (pp. 486–499). Lecture Notes in Computer Science. Springer Verlag. Peer-reviewed.
- Sastry, S., Welch, J. L., Widder, J. (2012). Wait-Free Stabilizing Dining Using Regular Registers. In Principles of Distributed Systems 16th International Conference, OPODIS 2012, Rome, Italy, December 18-20, 2012, Proceedings (pp. 284–299). LNCS / Springer. Peer-reviewed.
2011
- Charron-Bost, B., Fuegger, M., Welch, J. L., Widder, J. (2011). Brief announcement: full reversal routing as a linear dynamical system. In Proceedings of the 23rd ACM symposium on Parallelism in algorithms and architectures - SPAA ’11. SPAA ’11, San Jose, United States of America (the). ACM. Peer-reviewed.
- Charron-Bost, B., Függer, M., Welch, J. L., Widder, J. (2011). Full Reversal Routing as a Linear Dynamical System. In Structural Information and Communication Complexity (pp. 101–112). Springer Berlin / Heidelberg. Peer-reviewed.
- Charron-Bost, B., Függer, M., Welch, J. L., Widder, J. (2011). Partial is Full. In Structural Information and Communication Complexity (pp. 113–124). Springer Berlin / Heidelberg. Peer-reviewed.
2010
- Charron-Bost, B., Hutle, M., Widder, J. (2010). In search of lost time. Information Processing Letters, 110(21), 928–933. Peer-reviewed.
2009
- Charron-Bost, B., Gaillard, A., Welch, J., Widder, J. (2009). Routing without ordering. In Proceedings of the twenty-first annual symposium on Parallelism in algorithms and architectures - SPAA ’09. SPAA 2009 (Parallelism in Algorithms and Architectures), Calgary, Canada. ACM. Peer-reviewed.
- Charron-Bost, B., Welch, J. L., Widder, J. (2009). Link Reversal: How to Play Better to Work Less. In Algorithmic Aspects of Wireless Sensor Networks (pp. 88–101). Springer. Peer-reviewed.
- Widder, J., Schmid, U. (2009). The Theta-Model: achieving synchrony without clocks. Distributed Computing, 22(1), 29–47. Peer-reviewed.
- Biely, M., Widder, J. (2009). Optimal Message-Driven Implementations of Omega with Mute Processes. ACM Transactions on Autonomous and Adaptive Systems, 4(1). Peer-reviewed.
2007
- Biely, M., Charron-Bost, B., Gaillard, A., Hutle, M., Schiper, A., Widder, J. (2007). Tolerating Corrupted Communication. In 26th ACM Symposium on Principles of Distributed Computing (PODC’07) (pp. 244–253). Peer-reviewed.HDL: 20.500.12708/52017
- Biely, M., Hutle, M., Penso, L. D., Widder, J. (2007). Relating Stabilizing Timing Assumptions to Stabilizing Failure Detectors Regarding Solvability and Efficiency. In stabilization. Ninth International Symposium on Stabilization, Safety, and Security of Distributed Systems (SSS 2007), Paris, EU. Peer-reviewed.HDL: 20.500.12708/52032
- Widder, J., Gridling, G., Weiss, B., Blanquart, J.-P. (2007). Synchronous Consensus with Mortal Byzantines. In Proceedings of the 37th Annual IEEE/IFIP International Conference on Dependable Systems and Networks. IEEE Conference on Dependable Systems and Networks (DSN), Philadelphia, PA, United States of America (the). Peer-reviewed.HDL: 20.500.12708/52033
- Anceaume, E., Delporte-Gallet, C., Fauconnier, H., Hurfin, M., Widder, J. (2007). Clock Synchronization in the Byzantine-Recovery Failure Model. In International Conference On Principles Of DIstributed System (pp. 90–104). Peer-reviewed.HDL: 20.500.12708/52073
- Widder, J., Schmid, U. (2007). Booting Clock Synchronization in Partially Synchronous Systems with Hybrid Process and Link Failures. In Distributed Computing (pp. 115–140). Springer-Verlag. Peer-reviewed.HDL: 20.500.12708/25412
2006
- Függer, M., Handl, T., Steininger, A., Widder, J., Tögel, C. (2006). An Efficient Test for a Transition Signalling based Up-/Down-Counter. In Austrochip Mikroelektroniktagung (pp. 55–62). Peer-reviewed.HDL: 20.500.12708/51505 / Project: DARTS
- Biely, M., Widder, J. (2006). Optimal Message-Driven Implementations of Omega with Mute Processes. In Stabilization, Safety, and Security of Distributed Systems (pp. 110–121). Peer-reviewed.HDL: 20.500.12708/51523
- Albeseder, D., Widder, J. (2006). Simulating Distributed Real-Time Systems. In Junior Scientist Conference 2006 (pp. 83–84). Peer-reviewed.HDL: 20.500.12708/51573
2005
- Hutle, M., Widder, J. (2005). Self-Stabilizing Failure Detector Algorithms. In IASTED International Conference on Parallel and Distributed Computing and Networks (pp. 485–490). Peer-reviewed.HDL: 20.500.12708/51119
- Hutle, M., Widder, J. (2005). On the Possibility and the Impossibility of Message-Driven Self-Stabilizing Failure Detection. In Self Stabilizing Systems (pp. 153–170). Peer-reviewed.HDL: 20.500.12708/51122
- Widder, J., Le Lann, G., Schmid, U. (2005). Failure Detection with Booting in Partially Synchronous Systems. In Dependable Computing Conference - EDCC5 (pp. 20–37). Peer-reviewed.HDL: 20.500.12708/51123
- Hutle, M., Widder, J. (2005). Brief Announcement: On the Possibility and the Impossibility of Message-Driven Self-Stabilizing Failure Detection. In Proceedings of the 24th ACM Symposium on Principles of Distributed Computing (p. 208). Peer-reviewed.HDL: 20.500.12708/51124
- Hermant, J.-F., Widder, J. (2005). Implementing Reliable Distributed Real Time Systems with the Theta Model. In 9th International Conference on Principles of Distributed Systems (pp. 259–271). Peer-reviewed.HDL: 20.500.12708/51175
2004
- Hermant, J.-F., Widder, J. (2004). Implementing Time Free Designs for Distributed Real-Time Systems (A Case Study).HDL: 20.500.12708/32981
- Hutle, M., Widder, J. (2004). Time Free Self-Stabilizing Local Failure Detection.HDL: 20.500.12708/32982
- Hutle, M., Widder, J. (2004). On the Possibility and the Impossibility of Time Free Self-Stabilizing Failure Detection.HDL: 20.500.12708/32983
2003
- Widder, J., Le Lann, G., Schmid, U. (2003). Perfect failure detection with booting in partially synchronous systems.HDL: 20.500.12708/32910
- Widder, J., Schmid, U. (2003). Booting clock synchronization in partially synchronous systems with hybrid node and link failures.HDL: 20.500.12708/32911
Presentations
- Konnov, I., Lazić, M., Veith, H., Widder, J. (2016). Parameterized Verification of Liveness of Distributed Algorithms. Workshop on Formal Reasoning in Distributed Algorithms (FRiDA), Wien, Austria.HDL: 20.500.12708/86425 / Project:
- Lazić, M., Konnov, I., Veith, H., Widder, J. (2016). Model Checking of Threshold-based Fault-Tolerant Distributed Algorithms. 7th Workshop on Program Semantics, Specification and Verification: Theory and Applications, St. Petersburg, Russian Federation (the). Invited.HDL: 20.500.12708/86426 / Project:
- Konnov, I., Veith, H., Widder, J. (2012). Who is afraid of Model Checking Distributed Algorithms? Workshop on Exploiting Concurrency Efficiently and Correctly, Berkeley, United States of America (the).HDL: 20.500.12708/85358
- John, A., Konnov, I., Schmid, U., Veith, H., Widder, J. (2012). Counter Attack against Byzantine Generals. Alpine Verification Meeting, IST Austria, Austria.HDL: 20.500.12708/85359
- John, A., Konnov, I., Schmid, U., Veith, H., Widder, J. (2012). Parameterized Model Checking of Fault-tolerant Distributed Algorithms. Dagstuhl Seminar 12461: Games and Decisions for Rigorous Systems Engineering, Dagstuhl, Germany. Invited.HDL: 20.500.12708/85432
- John, A., Konnov, I., Schmid, U., Veith, H., Widder, J. (2012). Who is afraid of Model Checking Distributed Algorithms? PUMA/RISE Seminar, Traunkirchen, Austria.HDL: 20.500.12708/85435
- Függer, M., Widder, J. (2011). On Efficient Checking of Link-reversal-based Concurrent Systems. PUMA/RISE Seminar, Traunkirchen, Austria.HDL: 20.500.12708/85311
- Widder, J., Gridling, G., Weiss, B., Blanquart, J.-P. (2006). Synchronous Consensus with Mortal Byzantines. Dagstuhl Seminar 06371. From Security to Dependability, Dagstuhl, EU. Invited.HDL: 20.500.12708/84588
- Widder, J. (2004). The Theta-Model, and how to Boot Clock Synchronization in it. Seminaire Reflecs in INRIA Rocquencourt, Frankreich, INRIA Rocquencourt, Frankreich, Austria. Invited.HDL: 20.500.12708/84385
- Widder, J. (2004). VLSI Design and the Theta-Model (Kurzvorstellungen aktueller Forschung). Diskussionskreis Fehlertoleranz, Berlin, Austria.HDL: 20.500.12708/84387
- Widder, J. (2004). Why, Where and How to Use the Theta-Model. Seminaire Reflecs in INRIA Rocquencourt, Frankreich, INRIA Rocquencourt, Frankreich, Austria. Invited.HDL: 20.500.12708/84388
Theses
- Kukovec, J. (2024). SMT-driven techniques for verifying distributed systems [Dissertation, Technische Universität Wien]. reposiTUm.DOI: 10.34726/hss.2025.128661 / Download: PDF
- Tran, T. H. (2023). Symbolic verification of TLA+ specifications with applications to distributed algorithms [Dissertation, Technische Universität Wien]. reposiTUm.DOI: 10.34726/hss.2024.117518 / Download: PDF
- Stoilkovska, I. (2021). Modeling and verification of synchronous fault-tolerant distributed algorithms [Dissertation, Technische Universität Wien]. reposiTUm.DOI: 10.34726/hss.2021.90331 / Download: PDF
- Lazić, M. (2019). Reduction techniques for parameterized model checking and synthesis of fault-tolerant distributed algorithms [Dissertation, Technische Universität Wien]. reposiTUm.DOI: 10.34726/hss.2019.67803 / Download: PDF
- Gmeiner, A. (2015). Parameterized model checking of fault-tolerant distributed algorithms [Dissertation, Technische Universität Wien]. reposiTUm.DOI: 10.34726/hss.2015.33793 / Download: PDF
- Widder, J. (2004). Distributed computing in the presence of bounded asynchrony [Dissertation, Technische Universität Wien]. reposiTUm. https://resolver.obvsg.at/urn:nbn:at:at-ubtuw:1-13246HDL: 20.500.12708/14277 / Download: PDF
- Widder, J. (2002). Switching on : how processes initialize for consistent broadcast [Diploma Thesis, Technische Universität Wien]. reposiTUm. https://resolver.obvsg.at/urn:nbn:at:at-ubtuw:1-77756HDL: 20.500.12708/13550 / Download: PDF
Awards
- FIT-IT Embedded Systems Dissertationsstipendium "Distributed Computing in the Presence of Bounded Asynchrony"
2004 / Austria
And more…
Soon, this page will include additional information such as reference projects, activities as journal reviewer and editor, memberships in councils and committees, and other research activities.
Until then, please visit Josef’s research profile in TISS.