Co-founder and member of Board of Directors of Selected Areas in Cryptography, the annual international conference. Co-chair (1997, 1999, 2007, 2017); Member of the Program Committee (1994-1996, 1998, 2003-2004, 2006-2007, 2011-2013, 2015, 2017-2018); Chair of Board of Directors (2007-2013)
Area Editor for the journal IET Information Security (2005-2019).
Area Editor for the journal Security and Communication Networks (Wiley) (2009-2017).
Invited talk (SAC25: A Retrospective), University of Calgary, August 16, 2018.
Invited talk (The Impact of Shannon’s Work on Cryptography), The Shannon Conference: Claude Shannon Centenary, University of Ottawa, April 15, 2016.
Member of the Board of Advisors to the Office of the Privacy Commissioner of Canada (2006-2014).
Invited talk (Seminars on Sciences and Information Technologies series), Université de Québec en Outaouais, Montreal, Canada, March 11, 2014.
Invited talk (Distinguished Seminar series), Concordia University, Montreal, Canada, February 20, 2014.
Invited panel participation at the Messaging Malware and Mobile Anti-Abuse Working Group (M3AAWG), Montreal, Canada, October 23, 2013.
Six-month research sabbatical at the Office of the Privacy Commissioner of Canada (2013).
Invited talk (Turing: Some Significant Milestones in Cryptography and Cryptanalysis), 100th Anniversary of the birth of Alan Turing and his contribution to the modern world of computing, October 29, 2012.
Member of the Board of Advisors and Technical Contributor to Encyclopedia of Cryptography and Security, Second Edition, H. van Tilborg and S. Jajodia (Editors-in-Chief), Springer, 2011. Topics: Key Management (public and private), Identification, Security Standards. Had editorial or authorship responsibility for a total of 32 articles and definitions. (2009-2011).
Interim Director of the School of EECS, June – December, 2011.
Invited presentation: “Privacy in an Age of Exposure”, Workshop on Computer Privacy in E-Commerce, University of Montreal, May 1, 2010.
Invited presentation: “Credential Systems: Promise, Risks, and Possible Mitigations”, Identity, Privacy, and Security Institute (IPSI), University of Toronto, Canada, November 16, 2009.
Invited keynote presentation: “Credential Systems”, Information Systems Security (ISS) Colloquium, Concordia University, Montreal, Canada, June 5, 2009.
Invited presentation: Speaker on privacy issues in a half-day tutorial session entitled “On the Record” (to an audience of approximately 60 judges of all levels from across Canada), National Judicial Institute, Ottawa, Ontario, Canada, April 24, 2009.
Invited presentation: Speaker on privacy technologies in a half-day tutorial session on “Reasonable Expectation of Privacy” (to an audience of approximately 200 provincial court judges), National Judicial Institute, Canadian Association of Provincial Court Judges, Ottawa, Ontario, Canada, May 22, 2008.
Invited presentation: “Digital Credentials: Extensions for Real-World Use”, Ontario Research Network for Electronic Commerce (ORNEC) Workshop on Digital Credentials, Ottawa, Canada, February 5, 2008.
Invited Presentation: "Digital Credentials: Introduction and New Applications", 2nd Workshop on the Practice and Theory of IT Security, Montreal, QC, January 23, 2008.
General chair of the 7th Annual Workshop on Privacy Enhancing Technologies (PET 2007), Ottawa, Canada, June 20-22, 2007.
Invited presentation: "Delegation and Proxy Services in Digital Credential Environments", 7th Annual CACR Privacy and Security Workshop, Toronto, ON, Canada, November 2, 2006.
Invited to give the keynote presentation at the 2nd European PKI Workshop, Canterbury, U.K., June 30, 2005. The presentation was entitled PKI: Views from the Dispassionate "I".
Invited to give the keynote presentation at the Workshop on New Challenges for Access Control, Ottawa, Canada, April 27, 2005. The presentation was entitled Access Control: Current Approaches and New Challenges.
Member of the Program Committee for 13th ACM Conference on Computer and Communications Security (CCS), Alexandria, VA, October 30 - November 3, 2006.
Member of the Program Committee for Applied Cryptography and Network Security (ACNS), Singapore, June 6-9, 2006.
Member of the Program Committee for Workshop on Digital Identity Management (DIM) (held in conjunction with ACM Conference on Computer and Communications Security), Fairfax, VA, November 11, 2005.
Member of the Program Committee for 3rd Annual Conference on Privacy, Security & Trust, New Brunswick, Canada, October 12-14, 2005.
Member of the Program Committee for 4th International Workshop for Applied PKI (IWAP), Singapore, September 21-23, 2005.
Member of the Program Committee for 2nd European PKI Workshop (EuroPKI), Canterbury, U.K., June 31 - July 1, 2005.
Member of the Program Committee for Workshop on New Challenges for Access Control (NCAC), Ottawa, Canada, April 27, 2005.
Member of the Program Committee for Workshop on Practice and Theory of Access Control Technologies (WPTACT), Montreal, Quebec, Canada, January 19, 2005.
Member of the Program Committee for 1st European PKI Workshop (EuroPKI), Samos Island, Greece, June 25-26, 2004.
Member of the Program Committee for 7th Information Security Conference (ISC), Palo Alto, CA, USA, September 27-29, 2004.
Member of the Program Committee for 3rd International Workshop for Applied PKI (IWAP), Fukuoka, Japan, October 3-5, 2004.
Program Co-Chair for Workshop on Privacy and Security Aspects of Data Mining, Brighton, UK, November 1, 2004.
Member of the Program Committee for International Workshop on Practice and Theory in Public Key Cryptography (PKC), Les Diablerets, Switzerland, January 23-26, 2005.
Co-chair: Organization for the Advancement of Structured Information Standards (OASIS) eXtensible Access Control Markup Language (XACML) Technical Committee (2001-2003).
Member of the Board of Advisors and Technical Contributor to Encyclopedia of Cryptology and Information Security (Springer, 2005). Topics: Key Management (public and private), Identification, Authorization, Privacy, Security Standards .
Invited presentation: "Security Theme" (invited to speak as co-leader for the security theme), Privacy, Security & Trust Workshop, Montreal, Canada, October 27, 2003.
Invited presentation: “OASIS SAML Attribute Assertions: Description and Discussion”, at the 2nd Annual PKI Research Workshop, Gaithursburg, MD, USA, April 28, 2003 .
Invited presentation: “SAML: What’s Next?”, at the 2nd Annual PKI Research Workshop, Gaithursburg, MD, USA, April 29, 2003.
Member of the Program Committee for ACM Workshop on XML Security, Fairfax, VA, USA, October 31, 2003.
Member of the Program Committee for Joint OASIS/W3C Forum on Security Standards for Web Services, Boston, MA, USA, August 26, 2002.
Invited presentation: Secure Software Implementations for Wired and Wireless Applications, at the 9th University of Waterloo CACR (Center for Applied Cryptographic Research) Information Security Workshop, Ottawa, Canada, November 29, 2001.
Invited presentation: Which PKI is the Right One?, at the 7th ACM Conference on Computer and Communications Security, Athens, Greece, November 3, 2000.
Invited presentation: CAST Your Bread Upon the Waters, at the Communications and Information Technology Ontario (CITO) Knowledge Network Conference – Beyond the Edge: Road Mapping Innovation, Ottawa, Canada, October 2-3, 2000.
Invited presentation: Public-Key Infrastructure: Present Status and Future Directions, at the Communications and Information Technology Ontario (CITO) Tech Talk Workshop, Ottawa, Canada, February 3, 2000.
Principal organizer and moderator for "Layers of Security for the Electronic Age", Communications and Information Technology Ontario (CITO) Tech Talk Workshop, Ottawa, Canada, February 3, 2000.
Invited presentation: "PMI: Understanding the Unified Authorization Model", at the NATO technical subcommittee investigating Privilege Management Infrastructure, Ottawa, Canada, September 8, 1999.
Member of the Program Committee for 7th Usenix Security Symposium, San Antonio, TX, USA, January 26-29, 1998.
Member of the Program Committee for ACM Conference on Computer and Communications Security, Zurich, Switzerland, April 2-4, 1997.