December 2009: Winter Simulation Conference, Austin, TX, USA
July 2008: The 2008 International Conference on Communications in Computing (CIC 2008). July 14-17, 2008, Las Vegas, Nevada, USA
June 2008: Dependable Systems and Networks. ). June 24-27, 2008, Anchorage, AK, USA
Februar 2008: University of Bremen, Invited talk.
Spring 2008: Duke University, Lecture
December 2007: Winter Simulation Conference, Washington D.C., USA
Fall 2007: Duke University, Lectures
September 2007: The 7th International Conference on Next Generation Teletraffic and Wired/Wireless Advanced Networking (NEW2AN 2007), St.Petersburg, Russia [two talks]
August 2007: Second International Conference on Systems and Networks Communications (ICSNC 2007), Cap Esterel, French Riviera, France
August 2007: ChinaCom - International Conference on Communications and Networking in China, Shanghai, China.
September 2006: International EuroNGI Workshop on Self-Organizing Systems (IWSOS 2006), Passau, Germany
September 2006: 5th International Workshop on Ant Colony Optimization and Swarm Intelligence (ANTS2006), Bruxelles, Belgium
December 2005: Winter Simulation Conference, Orlando, FL, USA
October 2005: Norwegian Network Research Seminar, Oslo, Norway
September 2004: Rare Event Simulation and Combinatorial Optimization (RESIM COP 2004), Budapest, Hungary
October 2004: Norwegian Network Research Seminar, Trondheim, Norway
August 2004: 17th Nordic Teletraffic Seminar, Oslo, Norway
August 2003: Nordunet 2003, Reykjavik, Iceland.
June 2003: Uninett 2003, Høgskolen i Agder, 16-18 Juni 2003.
August 2002: 16. Nordiske Teletrafikk Seminar (NTS'16) in Espoo, Finland.
September 2000: ITC Specialist Seminar on IP Traffic Measurement, Modeling and Management, Monterey, CA (USA).
August 2000: 15. Nordiske Teletrafikk Seminar (NTS'15) in Lund, Sweden.
March 2000: University of Pisa, Invited guest lectures
January 2000: UNINETT testnet seminar, University of Tromsø, Norway
June 1999: 16th International Teletraffic Congress (ITC’16) - Impromptu session, Edinburg, UK
March 1999: Workshop on Rare Event Simulation (RESIM’99), University of Twente, The Netherlands
September 1998: 4th International Workshop on Performability Modeling of Computer and Communication Systems (PMCCS-4), Williamsburg, VA, USA.
August 1998: 14. Nordiske Teletrafikk Seminar (NTS'13) in Copenhagen, Denmark
June 1998: INFORMS International Meeting, Tel-Aviv Yafo, Israel
December 1997: Winter Simulation Conference 1997, Atlanta, Georgia, U.S.A.
August 1997: Workshop on Rare Event Simulation. Aachen, Germany, Invited Survey
June 1997: 15th International Teletraffic Congress (ITC'15) in Washington D.C. USA.
August 1996: 13. Nordiske Teletrafikk Seminar (NTS'13) in Trondheim, Norway
November 1995: International Teletraffic Seminar (ITS) in Bangkok, Thailand
August 1995: 12. Nordiske Teletrafikk Seminar (NTS'12) in Helsinki, Finland
June 1994: 14th International Teletraffic Congress (ITC'14) in Antibes Juan-les-Pins, France.
August 1993: 11. Nordiske Teletrafikk Seminar (NTS'11) in Stockholm, Sweden
August 1992: 10. Nordiske Teletrafikk Seminar (NTS'10) in Århus, Denmark
August 1992: Nordic Seminar on Dependable Computing systems (NSDCS'92) in Trondheim, Norway
October 1991: Safecomp'91 in Trondheim, Norway
November 1990: Feltolerante Datorsystem (FTDS'90) in Gothenburg, Sweden.