Dr. Nikos Passas
Communication Networks Laboratory
Dept. of Informatics & Telecommunications
University of Athens
Panepistimiopolis, Ilisia
15784, Athens - Greece
Tel: +30 210 7275651
Fax: +30 210 7275601
Email: passas@di.uoa.gr

 

Dr. Passas received his Diploma (honors) from the Department of Computer Engineering, University of Patras, Greece, and his Ph.D. degree from the Department of Informatics and Telecommunications, University of Athens, Greece, in 1992 and 1997, respectively. He is currently a member of the teaching staff in the Department of Informatics and Telecommunications of the University of Athens, and a group leader of the Green, Adaptive and Intelligent Networking (GAIN) research group inside the department. Over the years, he has participated and coordinated a large number of national and European research projects.  

Dr. Passas has served as a guest editor and technical program committee member in prestigious magazines and conferences, such as IEEE Wireless Communications Magazine, Wireless Communications and Mobile Computing Journal, IEEE Vehicular Technology Conference, IEEE PIMRC, IEEE Globecom, etc. He has published more than 120 papers in peer-reviewed journals and international conferences and has also published 1 book and 11 book chapters. His research interests are in the area of mobile network architectures and protocols. He is particularly interested in quality of service provision for wireless networks, medium access control, and mobility management.

Dr. Passas is a member of the IEEE and a member of the Technical Chamber of Greece.



 

Teaching assignments (Academic Year 2016-2017)

1. Mobile and personal communication systems (undergraduate course in Greek)

2. Wireless links (undergraduate course in Greek)

3. Mobile and wireless networks (graduate course in Greek)



 

Recent Projects

1. SMART-NRG: Industry-Academia partnership for the design and implementation of an efficient, reliable and secure smart energy network

2. CROSSFIRE: Uncoordinated network strategies for enhanced interference, mobility, radio resource, and energy saving management in LTE-Advanced networks

3. ReCRED: From Real-world Identities to Privacy-preserving and Attribute-based CREDentials for Device-centric Access Control

4. CASPER: A user-Centric middleware Architecture for advanced Service Provisioning in futurE netwoRks

5. SPOTLIGHT: Single Point Of aTtachment communications empowered by cLoud computing and bIG data analytics running on-top of massively distributed and loosely-coupled Heterogeneous mobile data neTworks



 

Guest Editor

1. A. Salkintzis and N. Passas, special issue on “The evolution of WLANs and PANs, IEEE Wireless Communications Magazine, vol. 10, no. 6, December 2003.

2. N. Passas and A. Salkintzis, special issue on “WLAN/3G Integration for Next-Generation Heterogeneous Mobile Data Networks, Wiley’s Wireless Communications and Mobile Computing Journal, vol. 5, no. 6, September 2005.

3. N. Passas, A. Salkintzis, D. Wong and V. Varma, special issue on “Architectures and Protocols for Mobility Management in All-IP Mobile Networks , IEEE Wireless Communications Magazine, vol. 15, no. 2, April 2008.

4. F. Bader, G. Chelius, C. Ibars, M. Ibnkahla, N. Passas, A.-R. Rhiemeier, “Simulators and Experimental Testbeds Design and Development for Wireless Networks, EURASIP Journal on Wireless Communications and Networking, April 2010.

 

 

Patents

1. F. Bauchot, G. Marmigere, L. Merakos, and N. Passas, “Traffic scheduling method, system and article of manufacture for a wireless access to an asynchronous transfer mode network, United States patent, Patent No. 6141336, October 2000.

 

 

Publications

Books

1. A. Salkintzis and N. Passas, editors, “Emerging Wireless Multimedia Services and Technologies , Wiley Press, ISBN: 0-470-02149-7, July 2005.

 

Book Chapters

2. N. Passas and L. Merakos, “Wireless ATM, book chapter in “The Wiley Encyclopedia on Telecommunications”, Wiley Press, editor: John Proakis, ISBN: 0-471-36972-1, January 2003.

3. N. Passas, “Internet Access over Wireless LANs”, book chapter in “Mobile Internet: Enabling Technologies and Services”, CRC Press, editor: Apostolis Salkintzis, ISBN: 0-849-31631-6, April 2004.

4. A. Salkintzis and N. Passas, “Mobile Internet”, book chapter in “Broadcasting and Optical Communication Technology”, CRC Press, editor: Richard C . Dorf, ISBN 978-0-8493-7338-1, 2006.

5. G. Lampropoulos, N. Passas, A. Kaloxylos and L. Merakos, “Integrated Wireless LANs (WLANs) and Cellular Networks: Managing Handovers”, book chapter in “The Encyclopedia of Wireless and Mobile Communications”, Auerbach Publications, editor: Borko Furkt, ISBN 1-420-04326-9, December 2007.

6. A.Kaloxylos, G. Modeas, N. Passas and G. Lampropoulos, “4G Mobile Systems: Radio Resource Management”, book chapter in “The Encyclopedia of Wireless and Mobile Communications”, Auerbach Publications, editor: Borko Furkt, ISBN 1-420-04326-9, December 2007.

7. D. Triantafyllopoulou, N. Passas and A. Kaloxylos, Cross-layer Design for Cooperative Wireless Communications, book chapter in “Cooperative Wireless Communications”, CRC Press, editors: Y. Zhang, H. H. Chen and M. Guizani, ISBN: 142006469X, March 2009.

8. D. Triantafyllopoulou, G. Lampropoulos, and N. Passas, Mobility Management for WLANs, book chapter in “Cross Layer Designs in WLAN Systems, Troubador Publishing Ltd, editors: N. Zorba, C. Skianis, and C. Verikoukis, ISBN: 9781848762275, April 2011.

9. D. Tsolkas, D. Xenakis, D. Triantafyllopoulou, and N. Passas, "Medium Access Control Layer", book chapter in "Advances on Processing for Multiple Carrier Schemes: OFDM & OFDMA", Nova Science Publishers, editors: F. Bader, and N. Zorba, ISBN: 978-1-61470-634-2, 4th quarter 2011.

10. D. Tsolkas, D. Xenakis, and N. Passas, "Next generation cognitive cellular networks, LTE, WiMAX and wireless broadband access", book chapter in "Cognitive Radio and its Application for Next Generation Cellular and Wireless Networks", Springer Publishers, editor: Hrishikesh Venkataraman, ISBN 978-94-007-1827-2, 2012.

11. D. Xenakis, N.Passas, A. Radwan, J. Rodriguez and C. Verikoukis, Energy Efficient Mobility Management for the Macrocell – Femtocell LTE Network”, book chapter in Energy Efficiency - The Innovative Ways for Smart Energy, the Future Towards Modern Utilities", InTech Publishers, editor: Moustafa Eissa, ISBN 978-953-51-0800-9, October 2012.

12. D. Tsolkas, E. Liotou, N. Passas, and L. Merakos, LTE-A Access, Core, and Protocol Architecture for D2D Communication”, book chapter in Smart Device to Smart Device Communication", Springer, editors: S. Mumtaz and J. Rodriguez, ISBN: 978-3-319-04963-2, 2014.

 

Journals/Magazines

13. N. Passas, N. Loukas and L. Merakos, “A Scheduling Technique for Bandwidth Allocation in Wireless Personal Communication Networks, International Journal of Wireless Information Networks, January 1997.

14. N. Passas and L. Merakos, “A Rate-Based Overload Control Method for the Radio Channel in PCN, ACM Wireless Networks Journal, vol. 3, no. 4, pp. 257-266, September 1997.

15. N. Passas, S. Paskalis, D. Vali and L. Merakos, “Quality-of-Service Oriented Medium Access Control for Wireless ATM Networks, IEEE Communications Magazine, vol. 35, no. 11, November 1997.

16. N. Passas, L. Merakos, D. Skyrianoglou, F. Bauchot, G. Marmigere and S. Decrauzat, “MAC Protocol and Traffic Scheduling for Wireless ATM Networks, special issue on Wireless LANs, ACM Mobile Networks and Applications Journal, vol. 3, no. 3, 1998.

17. N. Loukas, N. Passas, L. Merakos and I. Venieris, “A Signaling Architecture for Wireless ATM Access Networks, ACM Wireless Networks Journal, vol. 6, no. 2, 1999.

18. P. Mahonen, T. Saarinen, N. Passas, et. Al, “Platform-Independent IP Transmission over Wireless Networks: The WINE Approach, IEEE Wireless Communications Magazine, vol. 8, no. 6, December 2001.

19. N. Passas, E. Zervas, G. Hortopan, and L. Merakos, “A Flow Rejection Algorithm for QoS Maintenance in a Variable Bandwidth Wireless IP Environment, special issue on “All-IP Wireless Networks”, IEEE Journal on Selected Areas in Communications (JSAC), vol. 22, no. 4, May 2004.

20. N. Passas, S. Paskalis, A. Kaloxylos, et. al, “Enabling Technologies for the ¨Always Best Connected¨ Concept, Wiley Wireless Communications and Mobile Computing (WCMC) Journal, vol. 5, no. 2, March 2005.

21. A. Salkintzis, G. Dimitriadis, D. Skyrianoglou, N. Passas, F.-N. Pavlidou, “Seamless Continuity of Real-Time Video Across UMTS and WLAN Networks: Challenges and Performance Evaluation, special issue on “Towards Seamless Interworking of WLAN and Cellular Networks”, IEEE Wireless Communications Magazine, vol. 12, no. 3, June 2005.

22. N. Passas, A. Salkintzis, G. Nikolaidis, M. Katsamani, “A New Technique to Expedite RSVP Path Re-establishments in 802.11 Wireless LANs, Springer Wireless Personal Communications Journal, vol. 33, no. 1, April 2005.

23. G. Lampropoulos, N. Passas, L. Merakos, and A. Kaloxylos, Handover Management Architectures in Integrated WLAN/Cellular Networks, IEEE Communications Surveys and Tutorials, vol. 7, no. 4, December 2005.

24. A. Kaloxylos, G. Lampropoulos, N. Passas, and L. Merakos, A flexible handover mechanism for seamless service continuity in heterogeneous environments, special issue on “End-to-end QoS Provision Advances”, Elsevier Computer Communications Journal, vol. 29, no. 6, March 2006.

25. A. Floros, D. Skyrianoglou, N. Passas, T. Karoubalis, A Simulation Platform for QoS Performance Evaluation of IEEE 802.11e”, The Mediterranean Journal of Computers and Networks, vol. 2, no. 2, April 2006.

26. N. Passas, D. Skyrianoglou, and P. Mouziouras, “Prioritized Support of Different Traffic Classes in IEEE 802.11e Wireless LANs”, Elsevier Computer Communications Journal, vol. 29, no. 15, September 2006.

27. D. Skyrianoglou, N. Passas, and A. Salkintzis, ARROW: An Efficient Traffic Scheduling Algorithm for IEEE 802.11e HCCA, IEEE Transactions on Wireless Communications, vol. 5, no.12, December 2006.

28. G. Lampropoulos, N. Passas, A. Kaloxylos, and L. Merakos, A Flexible UMTS/WLAN Architecture for Improved Network Performance, special issue on “Seamless Handover in Next Generation Wireless Mobile Networks”, Springer Wireless Personal Communications Journal, vol. 43, no. 3, November, 2007.

29. D. Triantafyllopoulou, N. Passas, A. Salkintzis, and A. Kaloxylos, A Heuristic Cross-Layer Mechanism for Real-Time Traffic over IEEE 802.16 Networks, special issue on "Management Solutions for QoS Support over the Entire Audio-Visual Service Distribution Chain", Wiley International Journal of Network Management, vol. 17, no. 5, September/November 2007.

30. G. Lampropoulos, A. Salkintzis, and N. Passas, Media Independent Handover for Seamless Service Provision in Heterogeneous Networks, feature topic on "New Trends in Mobile Internet Technologies and Applications", IEEE Communications Magazine, vol. 46, no. 1, January 2008.

31. S. Xergias, N. Passas, and A. Salkintzis, Centralized Resource Allocation for Multimedia Traffic in IEEE 802.16 Mesh Networks, Proceedings of the IEEE, vol. 98, issue 1, January 2008.

32. A.K. Salkintzis, N. Passas, and D. Skyrianoglou, “On the Support of Voice Call Continuity across UMTS and Wireless LANs, Wiley Wireless Communications and Mobile Computing (WCMC) Journal, vol. 8, issue 7, September 2008.

33. D. Triantafyllopoulou, N. Passas, L. Merakos, S. Sagias, P.T. Mathiopoulos, E-CLEMA: A Cross-Layer Design for Improved Quality of Service in Mobile WiMAX Networks, Wiley Wireless Communications and Mobile Computing (WCMC) Journal, vol. 9, no. 9, pp. 1274-1286, September 2009.

34. A. Lygizou, S. Xergias, N. Passas, and L. Merakos, A Prediction-based Scheduling Mechanism for Interconnection between WiMax and Satellite NetworksInternational Journal of Autonomous and Adaptive Communications Systems, vol. 2, issue 2, 2009.

35. D. Triantafyllopoulou, N. Passas, A. Kaloxylos, and L. Merakos, Coordinated Handover Initiation and Cross-Layer Adaptation for Mobile Multimedia Systems, IEEE Transactions on Multimedia, special issue on "Quality-Driven Cross-Layer Design for Multimedia Communications", vol. 11, no. 6, pp. 1131-1139, October 2009.

36. I. Modeas, A. Kaloxylos, G. Lampropoulos, N. Passas, and L. Merakos, Radio Access Selection in Integrated UMTS/WLAN Networks, International Journal of Communications, Network and System Sciences, Scientific Research Publishing, vol. 2, no. 9, pp. 805-821, December 2009.

37. A. Kaloxylos, I. Modeas, F. Georgiadis, and N. Passas, Network Selection Algorithm for Heterogeneous Wireless Networks: from Design to Implementation, International Journal of Network Protocols and Algorithms, Scientific Research Publishing, vol. 1, no. 1, pp. 27-47, December 2009.

38. D. Xenakis, D. Tsolkas, N. Passas, N. Alonistioti, and L. Merakos, Dynamic Resource Allocation in Adaptive Wireless OFDMA Systems, Wiley Wireless Communications and Mobile Computing (WCMC) Journal, available online at Wiley Online Library, October 2010.

39. A. Lygizou, S. Xergias, N. Passas, Improved rtPS Scheduling with QoE metrics in Joint WiMAX / Satellite Networks, International Journal of P2P Network Trends and Technology, vol. 2, issue 1, pp. 4-12, 2011.

40. D. Triantafyllopoulou, N. Passas, E. Zervas, and L. Merakos, Analysis and Optimization of a Cross-Layer Adaptation Mechanism for Real-Time Applications in Wireless Networks”, Springer Wireless Networks (WINET) Journal, vol. 17, issue 5, July 2011.

41. A. Lygizou, N. Passas, S. Xergias, and L. Merakos, Effective Prediction for Video traffic in Joint WiMAX / Satellite Networks”, Springer Wireless Personal Communications Journal, June 2012.

42. D. Xenakis, N. Passas, and C. Verikoukis, An Energy-Centric Handover Decision Algorithm for the Integrated LTE Macrocell - Femtocell Network, special issue on Wireless Green Communications and Networking, Elsevier Computer Communications Journal, vol. 35, issue 14, August 2012.

43. D. Tsolkas, N. Passas, and L. Merakos, Increasing Spatial Spectrum Utilization through Opportunistic User-to-User Communications, Springer International Journal of Wireless Information Networks, vol. 20, issue 1, March 2013.

44. D. Tsolkas, N. Passas, and L. Merakos, Spatial Spectrum Reuse for Opportunistic Spectrum Access in Infrastructure-based Systems, Springer Wireless Personal Communications Journal, vol. 69, issue 4, April 2013.

45. D. Tsolkas, N. Passas, and L. Merakos, Alleviating Control Channel Interference in Femto-Overlaid LTE-Advanced Networks, IEEE Communications Magazine, vol. 51, issue 10, October 2013.

46. D. Xenakis, N. Passas, L. Merakos, and C. Verikoukis, Mobility Management for Femtocells in LTE-Advanced: Key Aspects and Survey of Handover Decision Algorithms, IEEE Communications Surveys and Tutorials, vol. 16, issue 1, First Quarter 2014.

47. D. Xenakis, N. Passas, and L. Merakos, Multi-Parameter Performance Analysis for Decentralized Cognitive Radio Networks, Springer Wireless Networks (WINET) Journal, vol. 20, issue 4, May 2014.

48. D. Xenakis, N. Passas, L. Merakos, and C. Verikoukis, Advanced Mobility Management for Reduced Interference and Energy Consumption in the Two-tier LTE-Advanced Network, Elsevier Computer Networks (COMNET) Journal, vol. 76, pp. 90111, Jan 2015.

49. E. Liotou, D. Tsolkas, N. Passas, and L. Merakos, Towards QoE Provisioning in Next Generation Cellular Networks”, IEEE COMSOC MMTC E-Letter, vol. 10, issue 3, May 2015.

50. E. Liotou, N. Passas, and L. Merakos, Quality of experience management in mobile cellular networks: key issues and design challenges”, IEEE Communications Magazine, vol. 53, issue 7, July 2015.

51. D. Tsolkas, N. Passas, and L. Merakos, Enabling Device Discovery Transmissions in LTE Networks with Fractional Frequency Reuse”, Elsevier Computer Networks (COMNET) Journal, vol. 88, pp. 149-160, Sept. 2015.

52. D. Xenakis, L. Merakos, M. Kountouris, N. Passas, and C. Verikoukis, Distance Distributions and Proximity Estimation given Knowledge of the Heterogeneous Network Layout, IEEE Transactions on Wireless Communications, vol. 14, issue 10, Oct. 2015.

53. D. Xenakis, N. Passas, L. Merakos, and C. Verikoukis, Handover Decision for Small Cells: Algorithms, Lessons Learned and Simulation Study”, Elsevier Computer Networks (COMNET), Computer Networks, Elsevier, Vol. 100, pp 64-74, May 2016.

54. D. Xenakis, N. Passas, L. Merakos, and C. Verikoukis, ANDSF-Assisted Vertical Handover Decisions in the IEEE 802.11/LTE-Advanced Network”, Elsevier Computer Networks (COMNET) Journal, vol. 106, September 2016.

55. D. Xenakis, M. Kountouris, L. Merakos, N. Passas, and C. Verikoukis, Performance Analysis of Network-Assisted D2D Discovery in Random Spatial Networks”, IEEE Transactions on Wireless Communications, vol. 15, no. 8, August 2016.

56. D. Tsolkas, N. Passas, and L. Merakos, Device discovery in LTE networks: A radio access perspective”, Elsevier Computer Networks (COMNET) Journal, vol. 106, September 2016.

57. D. Tsolkas, E. Liotou, N. Passas, and L. Merakos, A Survey on Parametric QoE Estimation for Popular Services”, Elsevier Journal of Network and Computer Applications (JNCA) , vol. 77, January 2017.

58. M. Jiang, D. Xenakis, S. Costanzo, N. Passas, and T. Mahmoodi, Radio Resource Sharing as a Service in 5G: A Software-defined Networking Approach”, Elsevier Computer Communications (COMCOM) Journal , accepted for publication.

59. S. Costanzo, D. Xenakis, N. Passas and L. Merakos, Augmented RAN with SDN Orchestration of Multi-tenant Base Stations”, Springer Wireless Personal Communications Journal , accepted for publication.



Conferences

60. N. Passas and L. Merakos, “Wait Time in Dynamic Bandwidth Allocation”, 5th Hellenic Conference on Informatics, Athens, December 1995.

61. N. Passas, N. Loukas and L. Merakos, “A Leaky-Bucket Based Scheduling Technique for Wireless Personal Communication Networks”, International Conference on Telecommunications, Istanbul, Turkey, April 1996.

62. N. Passas and L. Merakos, A Graceful Degradation Method for Congestion Control in Wireless Personal Communication Networks, IEEE Vehicular Technology Conference (IEEE VTC), Atlanta, GA, April 1996.

63. N. Passas and L. Merakos, A Rate-Based Overload Control Method for the Radio Channel in PCN, IEEE International Conference on Communications (IEEE ICC), Dallas, TX, June 1996.

64. N. Passas, D. Skyrianoglou, S. Outsios and L. Merakos, A Medium Access Control Framework for Wireless ATM Networks”, International Workshop on Mobile Communications, Thessaloniki, Greece, September 1996.

65. N. Passas, N. Loukas, A. Kaloxylos, T. Kuehnel and Y-S Wu, “Alternatives of Signalling Channel Allocation in Wireless ATM Networks”, International Workshop on Mobile Communications, Thessaloniki, Greece, September 1996.

66. F. Bauchot, G. Marmigere, N. Passas, L. Merakos and S. Decrauzat, “MASCARA: A MAC Protocol for Wireless ATM”, ACTS Mobile Communications Summit, Granada, Spain, November 1996.

67. F. Bauchot, N. Passas, G. Marmigere, L. Merakos and S. Decrauza, “MASCARA: A MAC Protocol for Wireless ATM”, International Conference on Telecommunications (ICT), Melbourne, Australia, April 1997.

68. N. Loukas, N. Passas, L. Merakos and I. Venieris, “Design of Call Control Signaling in Wireless ATM Networks, IEEE International Conference on Communications (IEEE ICC), Montreal, Canada, June 1997.

69. N. Passas and L. Merakos, “Traffic Scheduling in Wireless ATM Networks, IEEE ATM Workshop, Lisbon, Portugal, May 1997.

70. N. Passas, T. Korakis, E. Zervas and L. Merakos, “Improving Traffic Scheduling in Wireless ATM Networks”, IEEE Symposium on Computers and Communications, Athens, Greece, June-July 1998.

71. E. Zervas, A. Alonistioti and N. Passas, “A G-Transform based Systolic Array for Least Squares Problems”, European Signal Processing Conference (EUSIPCO), Rhodes Island, Greece, September 1998.

72. N. Passas, G. Lampropoulos and L. Merakos, “Dynamic Channel Assignment with Delay and Loss Considerations for Wireless TDMA LANs, IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (IEEE PIMRC), London, UK, September 2000.

73. N. Passas, G. Lampropoulos and L. Merakos, “A QoS-Oriented Dynamic Channel Assignment Method for Wireless ATM LANs”, IEEE Wireless Communications & Networking Conference (IEEE WCNC), Chicago, IL, September 2000.

74. D. Skyrianoglou, N. Passas and S. Kampouridou, “A DiffServ-based Classification Scheme for Internet Traffic Over Wireless Links, International Conference on Wireless LANs and Home Networks, Singapore, December 2001.

75. E. Zervas, N. Passas and R. Heaton, “A Sequential Blind Channel Estimation Technique for OFDM Systems”, International Conference on Communications, Rethymnon, Greece, July 2002.

76. E. Zervas, S. Liaskas, N. Passas and R. Heaton, “Pilot Assisted Clipping Avoidance for OFDM”, International Conference on Communications, Rethymnon, Greece, July 2002.

77. D. Skyrianoglou, N. Passas, and L. Merakos, “Improving QoS in a Multi-Hop Wireless Environment , Mediterranean Ad Hoc Networking Workshop, Sardegna, Italy, September 2002.

78. D. Skyrianoglou, N. Passas, A. Salkintzis, E. Zervas, “A Generic Adaptation Layer for Differentiated Services and Improved Performance in Wireless Networks, IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (IEEE PIMRC), Lisbon, Portugal, September 2002.

79. G.Lampropoulos, N. Frangiadakis, and N. Passas, “Enhancing Performance of IP Service in HIPERLAN/2 Networks, IEEE International Symposium on Wireless Personal Multimedia Communications (IEEE WPMC), Hawaii, USA, October 2002.

80. N. Passas, and L. Merakos, Unified QoS provision in wireless access networks , International Workshop on Wireless Mobile & Always Best Connected, Glasgow, UK, April 2003.

81. M. O'Droma, I. Ganchev, G. Morabito, R. Narcisi, N. Passas, S.Paskalis, V.Friderikos, A.S.Jahan, E.Tsontsis, C.Bader, J.Rotrou, H.Chaouchi,Always Best Connected Enabled 4G Wireless World”, 12th IST Summit on Mobile and Wireless Communications, Aveiro, Portugal, June 2003.

82. N. Passas, D. Skyrianoglou, and A. Salkintzis, Supporting UMTS QoS in WLANs, Personal Wireless Communications (PWC) 2003, Venice, Italy, September 2003.

83. N. Passas, E. Zervas and L. Merakos, Adaptable Resource Management in Wireless IP Links , IEEE Vehicular Technology Conference (IEEE VTC) 2003, Orlando, Florida, October 2003.

84. N. Passas, E. Zervas, G. Hortopan, and L. Merakos, Providing for QoS Maintenance in Wireless IP Environments, IEEE Global Communications Conference (IEEE GLOBECOM) 2003, San Francisco, CA, December 2003.

85. N. Passas and A. Salkintzis, “A New Scheme for Fast RSVP Reservations During Handover in Wireless IP Networks”, IP Based Cellular Networks (IPCN) 2003, Paris, France, December 2003.

86. D. Skyrianoglou and N. Passas, A Framework for Unified IP QoS Support Over UMTS and Wireless LANs, European Wireless 2004, Barcelona, Spain, February 2004.

87. M. Siebert, H. Chaouchi, I. Armuelles, N. Passas, I. Ganchev, M. O’Droma, “System and Service Integration in Heterogeneous Networks by a Policy Based Network Architecture”, European Wireless 2004, Barcelona, Spain, February 2004.

88. D. Skyrianoglou, A. Salkintzis and N. Passas, “Support of IP QoS over Wireless LANs”, IEEE Vehicular Technology Conference (IEEE VTC) Spring 2004, Milano, Italy, March 2004.

89. A. Salkintzis and N. Passas, “A New Approach for Fast Handovers in Mobile Multimedia Networks”, IEEE Vehicular Technology Conference (IEEE VTC) Spring 2004, Milano, Italy, March 2004.

90. D. Skyrianoglou, N. Passas, and A. Salkintzis, “Traffic Scheduling in IEEE 802.11e Networks Based on Actual Requirements”, Mobile Venue 2004, Athens, Greece, May 2004.

91. N. Passas, A. Salkintzis, G. Nikolaidis, and M. Katsamani, WLAN Signaling Enhancements for Improved Handover Performance, Wireless Personal Multimedia Communications (WPMC), Abano Terme, Italy, September 2004.

92. A. Salkintzis, D. Skyrianoglou, and N. Passas, “Seamless Multimedia QoS Across UMTS and WLAN Networks”, IEEE Vehicular Technology Conference (IEEE VTC) Spring 2005, Stockholm, Sweden, May 2005.

93. D. Skyrianoglou, N. Passas, and A. Salkintzis, Traffic Scheduling for Multimedia QoS Over Wireless LANs, IEEE International Conference on Communications (IEEE ICC) 2005, Seoul, Korea, May 2005.

94. G. Lampropoulos, N. Passas, A. Kaloxylos, and L. Merakos, “Connection-based Mobility Management for Seamless Service Continuity in Heterogeneous Networks”, International Workshop on Convergence of Heterogeneous Wireless Networks (ConWIN) 2005, Budapest, Hungary, July 2005. 

95. S. Xergias, N. Passas, and L. Merakos, Flexible Resource Allocation in IEEE 802.16 Wireless Metropolitan Area Networks”, 14th IEEE Workshop on Local and Metropolitan Area Networks (IEEE LANMAN), Chania, Greece, September 2005.

96. S. Xergias, A. Lygizou, N. Passas, and L. Merakos, “QoS Sensitive Traffic Scheduling in Broadband Wireless Mesh Networks”, 15th IST Summit on Mobile and Wireless Communications, Mykonos, Greece, June 2006.

97. S. Xergias, N. Passas, and L. Merakos, “Efficient Multicast Transmission in WiMax Mesh Networks”, IEEE International Conference on Communications (IEEE ICC) 2006, Workshop on IP over Broadcasting Networks, Istanbul, Turkey, June 2006.

98. G. Lampropoulos, N. Passas, L. Merakos, and A. Kaloxylos, “A Seamless Service Continuity Scheme for Enhanced Network Performance in UMTS/WLAN Networks”, 17th IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (IEEE PIMRC), Helsinki, Finland, September 2006.

99. A. Salkintzis, N. Passas, and D. Skyrianoglou, “Seamless Voice Call Continuity in 3G and WLANs”, 9th International Symposium on Wireless Personal Multimedia Communications (WPMC), San Diego, CA, September 2006.

100. D.-K. Triantafyllopoulou, N. Passas, and A. Kaloxylos, “A Cross-Layer Optimization Mechanism for Multimedia Traffic over IEEE 802.16 Networks”, European Wireless 2007, Paris, France, April 2007.

101. I. Modeas, A. Kaloxylos, N. Passas , and L. Merakos, An Algorithm for Radio Resources Management in Integrated Cellular/WLAN Networks, IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (IEEE PIMRC) 2007, Athens, Greece, September 2007.

102. G. Lampropoulos, A. Kaloxylos, N. Passas, and L. Merakos, A Power Consumption Analysis of Tight-Coupled WLAN/UMTS Networks, IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (IEEE PIMRC) 2007, Athens, Greece, September 2007.

103. D. Triantafyllopoulou, N. Passas, A.K. Salkintzis, and A. Kaloxylos, A Heuristic Cross-Layer Mechanism for Real-Time Traffic in IEEE 802.16 Networks, IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (IEEE PIMRC) 2007, Athens, Greece, September 2007.

104. A.K. Salkintzis, N. Passas, and S. Xergias, Performance Evaluation of Voice Call Transfer between UMTS and 802.16e”, Design & Developers Forum, IEEE GLOBECOM 2007, Washington D.C., November 2007.

105. D. Triantafyllopoulou, N. Passas, and A. Kaloxylos, Cross-Layer Adaptation for Real-Time Broadband Multimedia over IEEE 802.16e Networks, IEEE Broadband Multimedia Symposium 2008, Las Vegas, NV, April 2008.

106. S. Xergias, N. Passas, A. Lygizou, and A.K. Salkintzis, A Multimedia Traffic Scheduler for IEEE 802.16 Point-to-Multipoint Networks, IEEE International Conference on Communications (IEEE ICC) 2008, Beijing, China, May 2008.

107. D. Triantafyllopoulou, N. Passas, and A. Kaloxylos, Joint Application and Physical Layer Adaptation for Improved Performance in Wireless Networks, IEEE International Symposium on Wireless Pervasive Computing (IEEE ISWPC) 2008, Santorini, Greece, May 2008.

108. D. Xenakis, D. Tsolkas, S. Xergias, N. Passas, and L. Merakos, A Dynamic Subchannel Allocation Algorithm for IEEE 802.16e Networks, IEEE International Symposium on Wireless Pervasive Computing (IEEE ISWPC) 2008, Santorini, Greece, May 2008.

109. A. Lygizou, S. Xergias, N. Passas, and L. Merakos, A Prediction-based Scheduling Mechanism for Interconnection between WiMax and Satellite Networks, IEEE International Wireless Communications and Mobile Computing Conference (IEEE IWCMC) 2008, Chania, Greece, August 2008.

110. D. Triantafyllopoulou, N. Passas, and A. Kaloxylos, Integration of Handover in a Cross-Layer Mechanism for Mobile Multimedia Systems, IEEE International Communications Conference (IEEE ICC) 2009, Dresden, Germany, June 2009.

111. A. Kaloxylos, F. Georgiadis, I. Modeas, N. Passas, Design and Implementation of a Radio Access Selection Algorithm for Multi-mode Mobile Terminals, International ICST Conference on Mobile Networks and Management (MONAMI) 2009, Athens, Greece, October 2009.

112. Q.Bai, N.Passas and J.Nossek, Scheduling and resource allocation on OFDM and FBMC systems: an interactive approach and performance comparison, European Wireless 2010, Lucca, Italy, April 2010.

113. D. Xenakis, D. Tsolkas, N. Passas, and L. Merakos, Dynamic resource allocation in adaptive wireless multiuser multicarrier systems”, European Wireless 2010, Lucca, Italy, April 2010.

114. D. Triantafyllopoulou, N. Passas, E. Zervas, and L. Merakos “Optimized Cross-Layer Adaptation for Improved Resource Management in Wireless Networks”, The 8th International Symposium on Modeling and Optimization in Mobile, Ad-Hoc and Wireless Networks (WiOpt 2010), Workshop on Resource Allocation in Wireless Networks (RAWNET 2010), Avignon, France, June 2010.

115. A. Lygizou, and N. Passas, MF-TDMA slot allocation in Joint WiMAX / Satellite Networks, The 6th ACM International Wireless Communications and Mobile Computing Conference (IWCMC) 2010, Caen, France, June 2010.

116. S. Xergias, N. Passas, S. Sioutas, and L. Merakos, A joint traffic scheduling and slot allocation algorithm for mobile WiMAX Networks, The 21st IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (IEEE PIMRC 2010), Istanbul, Turkey, September 2010.

117. D. Tsolkas, D. Xenakis, N. Passas, and L. Merakos, “Opportunistic Spectrum Access over Mobile WiMAX Networks, The 15th IEEE International Workshop on Computer-Aided Modeling Analysis and Design of Communication Links and Networks (IEEE CAMAD) 2010, Miami, USA, December 2010.

118. D. Xenakis, N. Passas, L. Di Gregorio, and C. Verikoukis, “A Context-Aware Vertical Handover Framework Towards Energy-Efficiency, The 73rd IEEE Vehicular Technology Conference (IEEE VTC-Spring) 2011, Budapest, Hungary, May 2011.

119. D. Tsolkas, N. Passas, and L. Merakos, “Increasing Spectrum Utilization in Wireless Infrastructure-based Systems, The 16th IEEE Symposium on Computers and Communications (IEEE ISCC) 2011, Corfou, Greece, June 2011.

120. A. Lygizou, S. Xergias, and N. Passas, “rtPS Scheduling with QoE metrics in Joint WiMAX / Satellite Networks”, The 4th ICST Conference on Personal Satellite Services (PSATS) 2012, Bradford, UK, March 2012.

121. D. Xenakis, N. Passas, and C. Verikoukis, “ A Novel Handover Decision Policy for Reducing Power Transmissions in the two-tier LTE network, IEEE International Conference on Communications (IEEE ICC) 2012, Ottawa, Canada, June 2012.

122. A. Lygizou, N. Passas, and S. Xergias, Video traffic prediction for improved Scheduling in Joint WiMAX / Satellite Networks, The 8th IEEE International Wireless Communications & Mobile Computing Conference (IEEE IWCMC) 2012, Limassol, Cyprus, August 2012.

123. D. Tsolkas, E. Liotou, N. Passas, and L. Merakos, “ A Graph-Coloring Secondary Resource Allocation for D2D Communications in LTE Networks, The 17th IEEE International Workshop on Computer-Aided Modeling Analysis and Design of Communication Links and Networks (IEEE CAMAD) 2012, Barcelona, Spain, September 2012.

124. D. Xenakis, N. Passas, L. Merakos, and C. Verikoukis, “ Energy-Efficient and Interference-Aware Handover Decision for the LTE-Advanced Femtocell Network”, IEEE International Conference on Communications (IEEE ICC) 2013, Budapest, Hungary, June 2013.

125. D. Tsolkas, E. Liotou, N. Passas, and L. Merakos, “ Enabling D2D Communications in LTE Networks”, IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC) 2013, London, United Kingdom, September 2013.

126. D. Tsolkas, E. Liotou, N. Passas, and L. Merakos, “ The Need for QoE-driven Interference Management in Femtocell-Overlaid Cellular Networks”, 10th International Conference on Mobile and Ubiquitous Systems: Computing, Networking and Services (Mobiquitous) 2013 , Tokyo, Japan, December 2013.

127. S. Costanzo, D. Xenakis, N. Passas, and L. Merakos, “ OpeNB: A framework for Virtualizing Base Stations in LTE Networks”, IEEE International Conference on Communications (IEEE ICC) 2014 , Sydney, Australia, June 2014.

128. D. Xenakis, N. Passas, L. Merakos, and C. Verikoukis, “ ARCHON: An ANDSF-Assisted Energy-Efficient Vertical Handover Decision Algorithm for the Heterogeneous IEEE 802.11/LTE-Advanced Network”, IEEE International Conference on Communications (IEEE ICC) 2014 , Sydney, Australia, June 2014.

129. D. Tsolkas, N. Passas, L. Merakos, and A. Salkintzis, “ A Device Discovery Scheme for Proximity Services in LTE Networks”, IEEE Symposium on Computers and Communications (IEEE ISCC) 2014 , Madeira, Portugal, June 2014.

130. E. Liotou, E. Papadomichelakis, N. Passas, and L. Merakos, “ Quality of Experience-centric Management in LTE-A Mobile Networks: The Device-to-Device Communication Paradigm”, The 6th IEEE International Workshop on Quality of Multimedia Experience (IEEE QoMEX) 2014 , Singapore, September 2014.

131. E. Liotou, D. Tsolkas, N. Passas, and L. Merakos, “Ant Colony Optimization for enabling Device-to-Device communications”, The 19th IEEE International Workshop on Computer-Aided Modeling Analysis and Design of Communication Links and Networks (IEEE CAMAD) 2014 , Athens, Greece, December 2014.

132. E. Liotou, H. Elshaer, R. Schatz, R. Irmer, M. Dohler, N. Passas, and L. Merakos, “ Shaping QoE in the 5G ecosystem”, The 6th IEEE International Workshop on Quality of Multimedia Experience (IEEE QoMEX) 2014 , Costa Navarino, Greece, May 2015.

133. D. Tsolkas, E. Liotou, N. Passas, and L. Merakos, “ Addressing traffic demanding scenarios in cellular networks through QoE-based rate adaptation”, IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (IEEE PIMRC) 2015 , Hong Kong, China, August-September 2015.

134. D. Xenakis, M. Kountouris, L. Merakos, N. Passas, and C. Verikoukis, “On the Performance of Network-Assisted Device-to-Device Discovery”, IEEE Global Communications Conference (IEEE GLOBECOM) 2015 , San Diego, USA, December 2015.

135. E. Liotou, T. Hossfeld, C. Moldovan, F. Metzger, D. Tsolkas, and N. Passas, “Enriching HTTP adaptive streaming with context awareness: A tunnel case study”, IEEE International Conference on Communications (IEEE ICC) 2016 , Kuala Lumpur, Malaysia, May 2016.

136. E. Liotou, D. Tsolkas, and N. Passas, “A roadmap on QoE metrics and models”, 23rd International Conference on Telecommunications (ICT) , Thessaloniki, Greece, May 2016.

137. D. Tsolkas, and N. Passas, “Compensating Multiuser Synchronization Errors in 5G Communications: The Radio Resource Overhead”, 21st IEEE Symposium on Computers and Communications (IEEE ISCC) , Messina, Italy, June 2016.

138. E. Liotou, D. Tsolkas, K. Samdanis, N. Passas, and L. Merakos, “Towards Quality of Experience Management in the Next Generation of Mobile Networks”, European Conference on Networks and Communications (EuCNC) 2016, Athens, Greece, June 2016.

139. S. Tennina, D. Xenakis, M. Boschi, A. Colarieti, N. Passas, D. Tsolkas, “A System Level Simulator for Reliable Smart Energy Networks”, IEICE Information and Communication Technology Forum (ICTF) 2016, Patras, Greece, July 2016.

140. A. Tsiota, D. Xenakis, N. Passas, L. Merakos, “Jamming and Black Hole Attacks in the Smart Grid with Perfect Detection of Malicious Nodes”, IEICE Information and Communication Technology Forum (ICTF) 2016, Patras, Greece, July 2016.

141. D. Tsolkas, N. Passas, and L. Merakos, “ProVa: A Proximity Validation Approach For Enhanced Device Discovery”, IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (IEEE PIMRC) 2016, Valencia, Spain, September 2016.

142. E. Liotou, R. Schatz, A. Sackl, P. Casas, D. Tsolkas, N. Passas, and L. Merakos, “The Beauty of Consistency in Radio-Scheduling Decisions”, IEEE Global Communications Conference (IEEE GLOBECOM) 2016, Washington, DC USA, December 2016.

143. P.-V. Mekikis, A. Antonopoulos, E. Kartsakli, N. Passas, L. Alonso, and C. Verikoukis, “Stochastic Modeling of Wireless Charged Wearables for Reliable Health Monitoring in Hospital Environments”, IEEE International Conference on Communications (IEEE ICC) 2017, Paris, France, May 2017.