Bernard Stepien, University of Ottawa

Bernard Stepien

M.A. (Economics)
School of Information Technology and Engineering
University of Ottawa

Research Fellow


Bernard Stepien passed away on March 14th 2021. He was fighting prostate cancer. We are thankful for everything he has brought to the software development and testing community. He is survived by his wife Claudine, son Thomas and grandaughter Isabelle.



B.Stepien, Amy Felty, Resolving XACML Rule Conflicts using Artificial Intelligence in ICISS 2020 proceedings

B.Stepien, L. Peyton, Test Coordination and Dynamic Test Oracles for Testing Concurrent Systems in SOFTENG 2020 proceedings

B.Stepien, L. Peyton, Challenges of Cost Estimation for Software Testing in SOFTENG 2019 proceedings

B. Stepien, L. Peyton, M. Alhaj, Data-Driven Testing using TTCN-3, in SOFTENG 2018 proceedings

B. Stepien, L. Peyton, M. Alhaj, Model-based Visualization of Execution Traces and Testing Results, in IARA journals

N. Kesserwan, R. Dsouli, M. Bentahar, B. Stepien, P. Labreche, From Use Case Maps to Executable Test Procedures -A Scenario-based Approach, in Software and Systems Modeling Journal

M. Alhaj, K. Mallur, B. Stepien, L.Peyton, Towards a model-based approach for developing and QA of online business processes in ICICS 2017 proceedings

B. Stepien, L. Peyton, M. Alhaj, Visualizing Execution Models and Testing Results in SOFTENG 2017 proceedings

B.Stepien, Amy Felty, Using Expert Systems to Statically Detect "Dynamic" Conflicts in XACML, in ARES 2016 proceedings

B. Stepien, K. Mallur, L. Peyton, Testing Business Processes Using TTCN-3 in SDL Forum 2015 proceedings

P. Boulet, D. Amyot, B. Stepien, Towards the Generation of Tests in the Test Description Language from Use Case Maps Models to appear in proceedings of the SDL Forum 2015 proceedings

B. Stepien, B. Eze, L. Peyton, Testing Policy-Based e-Health Monitoring Processes Using TTCN-3 in Mcetech 2015 proceedings

B.Stepien, A. Felty, S. Matwin, Challenges of Composing XACML Policies, in ARES 2014 proceedings

B. Stepien, A. Felty, S. Matwin A Non-Technical XACML Target Editor for Dynamic Access Control Systems in proceedings ATS/SECOTS 2014

B. Stepien, L. Peyton, Challenges of Testing Periodic Messages in Avionics Systems Using TTCN-3 in proceedings ICTSS 2013

B. Stepien, L. Peyton, Innovation and evolution in integrated web application testing with TTCN-3 in International Journal on Software Tools for Technology Transfer

B.Stepien, A. Felty, S. Matwin, An Algorithm for Compression of XACML Access Control Policy Sets by Recursive Subsumption, in ARES 2012 proceedings

B. Stepien, L. Peyton, M. Shang, T. Vassiliou-Gioles, An Integrated TTCN-3 Test Framework Architecture for Interconnected Object-based Internet Applications in International Journal, Electronic Business, 2012

B. Stepien, H. Khambhammettu, K. Adi, L. Logrippo, CatBAC: A Generic Framework for Designing and Validating Hybrid Access Control Models, in ICC'12 WS - SFCS proceedings

B.Stepien, L.Peyton, P. Xiong, Using TTCN-3 as a Modeling Language for Web Penetration Testing, in ICIT'12 proceedings

B.Stepien, S.Matwin, A.Felty, Advantages of a Non-Technical XACML Notation in Role-Based Models, in the proceedings of the PST 2011 conference

B.Stepien, P.Xiong, L.Peyton, A Systematic Approach to Web Application Penetration Testing Using TTCN-3, in MCeTech 2011 proceedings

B.Stepien, S.Matwin, A.Felty, Strategies for Reducing Risks of Inconsistencies in Access Control Policies, in proceedings of the ARES 2010 conference

B.Stepien, A.Felty, S.Matwin A Non-technical User-Oriented Display Notation for XACML conditions in proceedings MCETECH 2009

P.Xiong, B.Stepien, L.Peyton Integration Testing of Web Applications and Databases Using TTCN-3 in proceedings MCETECH 2009

P.Xiong, B.Stepien, L.Peyton Model-Based Penetration Test Framework for Web Applicati ons using TTCN-3in proceedings MCETECH 2009

B.Stepien, L.Peyton, P.Xiong Framework Testing of Web Applications using TTCN-3- in STTT journal - Springer Verlag

L.Peyton, B.Stepien, P.Seguin Integration Testing of Composite Applications , HICSS'41

L.Peyton, B. Zhan, B.Stepien A Case Study in Integrated Quality Assurance for Performance Management Systems, in MVSVEIS 2008 proceedings

P.Seguin, L.Peyton, B.Stepien Open Source Integration Testing in OOPSLA'07 proceedings

V. Capretta, , B. Stepien, A. Felty, S. Matwin Formal Correctness of Conflict Detection for Firewalls in FMSE'07 Conference proceedings

Pulei Xiong, Robert L. Probert, Bernard Stepien, An Efficient Formal Testing Approach for Web Service with TTCN-3 in SoftCom'05 Conference proceedings

Robert L. Probert, Bernard Stepien, Pulei Xiong, Formal Testing of Web Content using TTCN-3 in TTCN-3 UserCom'05 Conference proceedings

Robert L. Probert, Pulei Xiong, Bernard Stepien, A Life-cycle E-Commerce Testing with OO-TTCN-3 in FORTE'04 Workshops proceedings

B.Stepien, I.Schieferdecker Automated Testing of XML/SOAP based Web Services, 2003 Leipzig Conference

B.Stepien, L.Logrippo Graphic Visualization and Animation of LOTOS Execution Traces , 2002 in Elsevier

D. Amyot, L. Charfi, N. Gorse, T. Gray, L. Logrippo, J. Sincennes, B. Stepien T. Ware. "Feature Description and Feature Interaction Analysis with Use Case Maps and LOTOS". To appear in the Proceedings of the Sixth International Workshop on Feature Interactions in Telecommunications and Software Systems, Glasgow, 17th - 19th May 2000.
(Available in MS-Word, B. Stepien T. Ware. "Feature and PDF)

Ina Schieferdecker, Bernard Stepien, Axel Rennoch und Mang Li Ein Ansatz zum Leistungstesten mit Anwendung auf ATM Protokolle, '3/98 in Praxis der informationsverarbeitung und Kommuniation, Saur publisher

Ina Schieferdecker, Bernard Stepien, Axel Rennoch PerfTTCN, a TTCN language extension for performance testing, IWTCS'97, Cheju Island, Korea

M. Faci, L. Logrippo, B. Stepien. Structural Models for Specifying Telephone Systems. in Computer Network and ISDN Systems, '97.

B. Stepien, K.Farooqui and L.Logrippo. An experience modelling telecommunications systems using ODP-DLcomp, FMOODS'96

B. Stepien and L.Logrippo. Feature interaction detection by using backward reasoning with LOTOS. In: S.T. Vuong and S.T. Chanson. Protocol Specification, Testing and Verification XIV. Chapman & Hall, 1995, 71-86.

Faci, M., Logrippo, L., and StÚpien, B. Formal Specification of Telephone Systems in LOTOS: The Constraint-Oriented Approach. Computer Networks and ISDN Systems 21 (1991) 53-67.

Bernard Stepien and Luigi Logrippo, Representing and Verifying Intentions in Telephony Features Using Abstract Data Types, IFW'95, Kyoto, Japan

Stepien, B., and Logrippo, L. Status-Oriented Telephone Service Specification. In: T.Rus and C.Rattray (eds.) Theories and Experiences for Real-Time System Development. AMAST Series in Computing, Vol. 2, World Scientific, 1994

B.Stepien and Luigi Logrippo, The suspend and resume operator. Canadian contribution to the ISO WG 7, Madrid 1994

M.Faci, L.Logrippo, B.Stepien, Formal Specification of telephone systems in LOTOS,(1989) Protocol, Verification and testing, IX, North-Holland

B.Stepien and C.Ward, Bell Canada's Generic Network Element Control Technology. INFOCOM'91, Phoenix, AZ 1991

Research Topics

Access Control Management - Policy conflict detection

Testing and Test Control Notation(TTCN-2 and TTCN-3)

Transportation Science

Eclipse Test & Performance Tools Platform Project

LOTOS Graphic Animation (MSC generation, virtual terminal modelling)

PerfTTCN (Real Time TTCN for performance testing)

GPRS (Global Packet Radio Service) specification

Feature interactions detection in telephone systems

Backward Reasonning in LOTOS

LOTOS Specifications styles - Status Oriented Style

Specifying Telephony applications using LOTOS

LOTOS Tutorial with PC DOS animation

Visualization of the execution of LOTOS specification

ODP Object description language

Abstract Data Types

Abstract Data Types Extentions Tool pao2ao
Abstract Data Types Editor Tool


Community radio
Automated 16th Century German Lute Tablatures
Phone(613) 562-5800 ext. 6723
Fax(613) 733-6783