Konstantinos (Kostas) Christodoulopoulos

Nokia Bell Labs, Stuttgart

Konstantinos.1.christodoulopoulos at nokia-bell-labs dot com

I am a member of technical staff in Nokia Bell Labs, Stuttgart.

I hold the Diploma of Electrical and Computer Engineering (ECE) from National Technical University of Athens (NTUA). I obtained the M.Sc in Advance Computing from Imperial College of London, U.K., in 2004, and the Ph.D degree from the Department of Computer Engineering and Informatics (CEID), University of Patras, Greece, in 2009. I worked as an adjunct assistant professor at the same department from 2009 to 2011. I also worked as a senior researcher at the School of Computer Science and Statistics, Trinity College Dublin and as a contractor for I.B.M. Research Ireland, at CEID/UPatras, and ECE/NTUA.

My main research interests are in the areas of algorithms and protocols for optical and high speed networks, and networks for distributed and parallel computing systems.

Journal Articles

[J57] F. Locatelli, K. Christodoulopoulos, M. Svaluto Morelo, J. M. Fabrega, S. Spadaro, “Machine Learning-Based in-band OSNR Estimation from Optical Spectra“, IEEE Photonic Technology Letters (PTL), to appear.

[J56] K. Christodoulopoulos, C. Delezoide, N. Sambo, A. Kretsis, I. Sartzetakis, A. Sgambelluri, N. Argyris, G. Kanakis, P. Giardina, G. Bernini, D. Roccato, A. Percelsi, R. Morro, H. Avramopoulos, P. Castoldi, P. Layec, S. Bigo, “Toward efficient, reliable, and autonomous optical networks: the ORCHESTRA solution”, IEEE/OSA Journal of Optical Communications and Networking 2019. [Invited]

[J55] N. Sambo, K. Christodoulopoulos, N. Argyris, P. Giardina, C. Delezoide, D. Roccato, A. Percelsi, R. Morro, A. Sgambelluri, A. Kretsis, G. Kanakis, G. Bernini, E. Varvarigos, P. Castoldi, “Field Trial: Demonstrating Automatic Reconfiguration of Optical Networks based on Finite State Machine”, IEEE/OSA, Journal of Lightwave Technology, 2019. [Invited]

[J54] C. Delezoide, K. Christodoulopoulos, A. Kretsis, N. Argyris, G. Kanakis, A. Sgambelluri, N. Sambo, P. Giardina, G. Bernini, D. Roccato, A. Percelsi, R. Morro, H. Avramopoulos, E Varvarigos, P. Castoldi, P. Layec, S. Bigo, “Marginless Operation of Optical Networks”, IEEE/OSA, Journal of Lightwave Technology, 2019. [Invited]

[J53] I. Sartzetakis, K. Christodoulopoulos, E. Varvarigos, “Accurate quality of transmission estimation with machine learning”, IEEE/OSA, Journal of Optical Communications and Networking, 2019.

[J52] N. Sambo, K. Christodoulopoulos, N. Argyris, P. Giardina, C. Delezoide, A. Sgambelluri, A. Kretsis, G. Kanakis, F. Fresi, G. Bernini, H. Avramopoulos, E. Varvarigos, P. Castoldi, “Experimental Demonstration of a Fully Disaggregated and Automated White Box Comprised of Different Types of Transponders and Monitors”, IEEE/OSA Journal of Lightwave Technology, 2019.

[J51] A. Siokis, K. Christodoulopoulos, E. Varvarigos, “Layout model for optical interconnects based on λ-routing grids and topology embeddings”, IEEE/OSA, Journal of Optical Communications and Networking, 2018.

[J50] I. Sartzetakis, N. Sambo, K. Christodoulopoulos, P. Castoldi, E. Varvarigos, “Exploiting spectrum sharing for soft failure recovery”, IEEE/OSA, Journal of Optical Communications and Networking, 2018.

[J49] G. Landi, M. Capitani, A. Kretsis, K. Kontodimas, P. Kokkinos, D. Gallico, M. Biancani, K. Christodoulopoulos, E. Varvarigos, “Inter-domain optimization and orchestration for optical datacenter networks”, IEEE/OSA, Journal of Optical Communications and Networking, 2018.

[J48] I. Gravalos, P. Makris, K. Christodoulopoulos, E. Varvarigos, "Efficient Network Planning for Internet of Things with QoS Constraints", IEEE Journal of Internet of Things, 5 (5), 2018.

[J47] P. Bakopoulos, K. Christodoulopoulos, G. Landi, M. Aziz, E. Zahavi, D. Gallico, R. Pitwon, K. Tokas, I. Patronas, M. Capitani, C. Spatharakis, K. Yiannopoulos, K. Wang, K. Kontodimas, I. Lazarou, P. Wieder, D. Reisis, E. Varvarigos, M. Biancani, H. Avramopoulos, “NEPHELE: An End-to-End Scalable and Dynamically Reconfigurable Optical Architecture for Application-Aware SDN Cloud Data Centers”, IEEE Communications Magazine, 2018.

[J46] I. Sartzetakis, N. Sambo, K. Christodoulopoulos, P. Castoldi, E. Varvarigos, “Exploiting Spectrum Sharing for Soft Failure Recovery” , IEEE/OSA Journal of Optical Communications and Networking, 2018.

[J45] P. Papanikolaou, K. Christodoulopoulos, E. Varvarigos, “Optimization Techniques for Incremental Planning of Multilayer Elastic Optical Networks”, IEEE/OSA Journal of Optical Communications and Networking, 2018.

[J44] G. Landi, M. Capitani, A. Kretsis, K. Kontodimas, P. Kokkinos, D. Gallico, M. Biancani, K. Christodoulopoulos, E. Varvarigos, “Inter-Domain Optimization and Orchestration for Optical Datacenter Networks”, IEEE/OSA Journal of Optical Communications and Networking, 10 (7), 2018.

[J43] I Sartzetakis, K Christodoulopoulos, E Varvarigos, “Cross-Layer Adaptive Elastic Optical Networks”, IEEE/OSA Journal of Optical Communications and Networking (JOCN), 2018. [Invited]

[J42] P. Soumplis, K. Christodoulopoulos, M. Quagliotti, A. Pagano, E. Varvarigos, “Multi-Period Planning With Actual Physical and Traffic Conditions”, IEEE/OSA Journal of Optical Communications and Networking (JOCN), 2018. [Invited]

[J41] K Christodoulopoulos, K Kontodimas, A Siokis, K Yiannopoulos, E. Varvarigos, "Efficient bandwidth allocation in the NEPHELE optical/electrical datacenter interconnect", IEEE/OSA Journal of Optical Communications and Networking (JOCN), 2017.

[J40] P. Soumplis, K. Christodoulopoulos, M. Quagliotti, A. Pagano, E. Varvarigos, "Network Planning with Actual Margins", IEEE/OSA Journal of Lightwave Technology (JLT), to appear

[J39] A. Siokis, K. Christodoulopoulos, N. Pleros, E. Varvarigos, "Electro-optic switches based on space switching of multiplexed WDM signals: Blocking vs non-blocking design trade-offs", Elsevier Optical Switching and Networking 25, pp. 40-56, 2017

[J38] P. Maniotis, N. Terzenidis, A. Siokis, K. Christodoulopoulos, E. Varvarigos, M. Immonen, H. J. Yan, L. X. Zhu, K. Hasharoni, R. Pitwon, K. Wang, N. Pleros, "Application-oriented On-board Optical Technologies for HPCs", IEEE/OSA Journal of Lightwave Technology (JLT), 2017

[J37] P. Papanikolaou, K. Christodoulopoulos, E. Varvarigos, "Joint multi-layer survivability techniques for IP-over-elastic-optical-networks", IEEE/OSA Journal of Optical Communications and Networking (JOCN), 9 (1), 2017

[J36] A. Siokis, K. Christodoulopoulos, E. Varvarigos, " Multipoint Architectures for On-Board Optical Interconnects", IEEE/OSA Journal of Optical Communications and Networking (JOCN), Vol. 8 is. 11, 2016.

[J35] I. Sartzetakis, K. Christodoulopoulos, C. Tsekrekos, D. Syvridis, E. Varvarigos, "Quality of transmission estimation in WDM and elastic optical networks accounting for space–spectrum dependencies", IEEE/OSA Journal of Optical Communications and Networking (JOCN), Vol. 8, is. 9, 2016

[J34] M.S. Moreolo, J.M. Fabrega, L. Martín, K. Christodoulopoulos, E. Varvarigos, J. P. F. Palacios, " Flexgrid Technologies Enabling BRAS Centralization in MANs", IEEE/OSA Journal of Optical Communications and Networking (JOCN), Vol. 8, is. 7, 2016

[J33] V. Gkamas, K. Christodoulopoulos, D.J. Vergados, E. Varvarigos, "Energy-minimized design of IP over flexible optical networks", Wiley International Journal of Communication Systems, 2015.

[J32] V. Gkamas, K. Christodoulopoulos, E. Varvarigos, "A joint multi-layer planning algorithm for IP over flexible optical networks", IEEE/OSA Journal of Lightwave Technology (JLT), Vol. 33, Is. 14, 2015.

[J31] K. Christodoulopoulos, C. Papageorgiou, E. Varvarigos, "Minimizing Expected Transmissions Multicast in Wireless Multihop Networks", Springer International Journal of Wireless Information Networks: Vol. 22, Is. 3, pp. 205-219, 2015.

[J30] P. Papanikolaou, P. Soumplis, K. Manousakis, G. Papadimitriou, G. Ellinas, K. Christodoulopoulos, E. Varvarigos, "Minimizing Energy and Cost in fixed-grid and flex-grid networks", IEEE/OSA Journal of Optical Communications and Networking (JOCN), Vol. 7, Is. 4, 2015.

[J29] K. Christodoulopoulos, D. Lugones, K. Katrinis, M. Rufinni, D. O'Mahony, "Performance Evaluation of a Hybrid Optical/Electrical Interconnect", IEEE/OSA Journal of Optical Communications and Networking (JOCN), Vol. 7, Is. 3, 2015.

[J28] P. Soumplis, K. Christodoulopoulos, E. Varvarigos, "Dynamic Connection Establishment and Network Re-optimization in Flexible Optical Networks", Springer Photonic Network Communications (PNC), 2015. [Invited]

[J27] A. Kretsis, P. Kokkinos, K. Christodoulopoulos, T. Varvarigou, E. Varvarigos, "Mantis: Cloud-based optical network planning and operation tool", Elsevier Compute Networks, Vol. 77, pp. 153-168, 2015.

[J26] E. Varvarigos, K. Christodoulopoulos, "Algorithmic Aspects in Planning Fixed and Flexible Optical Networks With Emphasis on Linear Optimization and Heuristic Techniques", IEEE/OSA Journal Lightwave Technology (JLT), Vol 32, Is. 4, pp. 681-693, 2014. [Invited]

[J25] A Kretsis, K Christodoulopoulos, P Kokkinos, E Varvarigos, "Planning and operating flexible optical networks: Algorithmic issues and tools", IEEE Communications Magazine, Vol. 52, Is. 1, pp. 61-69, 2014.

[J24] K. Christodoulopoulos, P. Soumplis, E. Varvarigos, "Planning flexible optical networks under physical layer constraints", IEEE/OSA Journal of Optical Communications and Networking, (JOCN), Vol. 5, Is. 11, pp. 1296-1312, 2013.

[J23] K. Christodoulopoulos, K. Katrinis, M. Ruffini, D. O' Mahony, "Tailoring the Network to the Problem: Topology Configuration in Hybrid EPS/OCS Interconnects", Willey Interscience Concurrency and Computation: Practice and Experience, Vol. 25, Is. 17, pp. 2412-2432, 2013.

[J22] K. Christodoulopoulos, I. Tomkos, E. Varvarigos, "Time-Varying Spectrum Allocation Policies in Flexible Optical Networks", IEEE Journal on Selected Areas in Communication (JSAC), Vol 31, Is. 1, pp. 13-25, 2013.

[J21] E. Palkopoulou, M. Angelou, D. Klonidis, K. Christodoulopoulos, A. Klekamp, F. Buchali, E. Varvarigos, I. Tomkos, "Quantifying spectrum, cost, and energy efficiency in fixed-grid and flex-grid networks", IEEE/OSA Journal of Optical Communications and Networking, Nov, 2012 [Invited]

[J20] K. Christodoulopoulos, K. Manousakis, E. Varvarigos, "Reach Adapting Algorithms for Mixed Line Rate WDM Transport Networks", IEEE/OSA Journal of Lightwave Technology, Vol 29, Is. 21, 2011.

[J19] K. Christodoulopoulos, P. Kokkinos, E. Varvarigos, "Indirect and Direct Multicost Algorithms for Online Impairment-Aware RWA", IEEE/ACM Transactions on Networking, Vol 19, Is. 6, 2011.

[J18] K. Christodoulopoulos, I. Tomkos, E.Varvarigos, "Elastic Bandwidth Allocation in Flexible OFDM-based Optical Networks", IEEE/OSA Journal of Lightwave Technology, 2011.

[J17] P. Kokkinos, K. Christodoulopoulos, E. Varvarigos, "Efficient Data Consolidation in Grid Networks", Future Generation Computer Systems, Elsevier, Vol. 27, Is. 2, 2011.

[J16] K. Christodoulopoulos, P. Kokkinos, K. Manousakis, E. Varvarigos, "Impairment Aware RWA in optical networks: over-provisioning or cross optimization?", Journal of Networks, Special Issue on All-Optical Routing, Vol. 5, No. 11, 2010.

[J15] K. Christodoulopoulos, K. Manousakis, E. Varvarigos, "Offline Routing and Wavelength Assignment in Transparent WDM Networks", IEEE/ACM Transactions on Networking, Vol. 18, Is. 5, 2010.

[J14] K. Manousakis, P. Kokkinos, K. Christodoulopoulos, E. Varvarigos, "Joint Online Routing, Wavelength Assignment and Regenerator Allocation in Translucent Optical Networks", IEEE/OSA Journal of Lightwave Technology, Vol. 28, is. 8, pp. 1152-1163, Apr. 2010.

[J13] T. Stevens, M. De Leenheer, C. Develder, B. Dhoedt, K. Christodoulopoulos, P. Kokkinos, E. Varvarigos, "Multi-Cost Job Routing and Scheduling in Grid Networks", Future Generation Computer Systems, Elsevier, Vol. 25, Is. 8, pp. 912-925, Sept. 2009.

[J12] K. Manousakis, K. Christodoulopoulos, E. Kamitsas, I. Tomkos, E. Varvarigos, "Offline Impairment-Aware Routing and Wavelength Assignment Algorithms in Translucent WDM Optical Networks", IEEE/OSA Journal of Lightwave Technology, Vol. 27, Is. 12, pp. 1866 - 1877, June, 2009.

[J11] K. Christodoulopoulos, K. Manousakis, E. Varvarigos, M. Angelou, "Considering Physical Layer Impairments in Offline RWA", IEEE Network Magazine, Vol. 23, Is. 3, pp. 26-33, 2009.

[J10] K. Christodoulopoulos, V. Sourlas, I. Mpakolas, E. Varvarigos, "A Comparison of Centralized and Distributed Meta-Scheduling Architectures for Computation and Communication Tasks in Grid Networks", Computer Communications, Elsevier, Vol. 32, Is. 7-10, pp. 1172-1184, May 2009.

[J9] E. Varvarigos, V. Sourlas, K. Christodoulopoulos, "Routing and Scheduling Connections in Networks that Support Advance Reservations", Computer Networks, Elsevier, Vol. 52, no. 15, pp. 2988-3006, Oct. 2008.

[J8] K. Christodoulopoulos, E. Varvarigos, K. Vlachos, "A new Burst Assembly Scheme based on the Average Packet Delay and its Performance for TCP Traffic", Journal of Optical Switching and Networking, Elsevier, Vol. 4, no. 3-4, pp. 200-212, Nov. 2007.

[J7] R. V. Caenegem, D. Colle, M. Pickavet, P. Demeester, K. Christodoulopoulos, K. Vlachos, E. Varvarigos, L. Stampoulidis, D. Roccato, R. Vilar, "The Design of an All-Optical Packet-Switching Network", IEEE Communications Magazine, Vol. 45, no. 11, pp. 52 - 61, Nov. 2007.

[J6] K. Christodoulopoulos, V. Gkamas, E. Varvarigos, "Statistical Analysis and Modeling of Jobs in a Grid Environment", Journal of Grid Computing, Springer, Vol. 6, pp. 77-101, Nov. 2007.

[J5] K. Vlachos, E. Van Breusegem , K. Christodoulopoulos, D. Colle , K. Ramantas, P. Demeester, "Constrained and Unconstrained Overspill Routing in Optical Networks: A Detailed Performance Evaluation", Photonic Network Communications, Springer, Vol. 13, No. 3, pp. 227-240, June 2007.

[J4] J. Aracil, N. Akar, S. Bjornstad, M. Casoni, K. Christodoulopoulos, D. Careglio, J. Fdez-Palacios, C. Gauger, O. Gonzalez de Dios, G. Hu, E. Karasan, M. Klinkowski, D. Morato, R. Nejabati, H. Overby , C. Raffaelli, D. Simeonidou, N. Stol, G. Tosi-Beleffi, K. Vlachos, "Research in Optical Burst Switching within the e-Photon/ONe Network of Excellence", Journal of Optical Switching and Networking, Elsevier, Vol. 4, Is. 1, pp. 1-19, Feb. 2007.

[J3] K. Manousakis, V. Sourlas, K. Christodoulopoulos, E. A. Varvarigos, K. Vlachos, "A Bandwidth Monitoring Mechanism Enhancing SNMP to Record Timed Resource Reservations", Journal of Network and Systems Management, Springer, Vol. 14, No. 4, pp. 583-597, Dec 2006.

[J2] E. Kehayas, K. Vyrsokinos,L. Stampoulidis, K. Christodoulopoulos, K. Vlachos, H. Avramopoulos "ARTEMIS: A 40 Gb/s All-Optical Self-Routing Node and Network Architecture employing Asynchronous Bit and Packet-Level Optical Signal Processing", IEEE/OSA Journal of Lightwave Technology, Vol. 24, no.8, pp. 2967-2977, Aug. 2006.

[J1] K. Christodoulopoulos, L. SpellE>Stampoulidis, E. Kehayas, K. Vlachos, E. Varvarigos, "Efficient burst reservation protocol: a hybrid signaling protocol for efficient burst-level reservations and quality-of-service differentiation in optical burst switching networks", OSA Journal of Optical Networking, Vol 5, Is. 3, 2006.

Conference Articles

[C63] A. Mahajan K. Christodoulopoulos, R. Martinez, S. Spadaro, R. Munoz, "Machine Learning Assisted EDFA Gain Ripple Modelling for Accurate QoT Estimation", European Conference on Optical Communication (ECOC), 2019.

[C62] K. Kontodimas, K. Christodoulopoulos, E. Varvarigos, "Simplifying Optical DCN Fabrics with Blocking Space Switching and Wavelength-Constrained WDM", International Conference on Optical Network Design and Modeling (ONDM), 2019.

[C61] C. Delezoide, K. Christodoulopoulos, A. Kretsis, N. Argyris, G. Kanakist, A. Sgambelluri, N. Sambo, P. Giardina, G. Bernini, D. Roccato, A. Percelsi, R. Morro, H. Avramopoulos, E. Varvarigos, P. Castoldi, P. Layec, S. Bigο, "Field trial of marginless operations of an optical network facing ageing and performance fluctuations", European Conference on Optical Communication (ECOC), 2018.

[C60] K. Tokas, C. Spatharakis, I. Patronas, P. Bakopoulos, G. Landi, K. Christodoulopoulos, M. Capitani, A. Kyriakos, M. Aziz, R. Pitwon, D. Gallico, D. Reisis, E. Varvarigos, E. Zahavi, H. Avramopoulos, "Real time demonstration of an end-to-end optical datacenter network with dynamic bandwidth allocation", European Conference on Optical Communication (ECOC), 2018.

[C59] I. Sartzetakis, K. Christodoulopoulos, E. Varvarigos, "Formulating QoT estimation with machine learning", European Conference on Optical Communication (ECOC), 2018.

[C58] N. Sambo, K. Christodoulopoulos, N. Argyris, P. Giardina, C. Delezoide, D. Roccato, A. Percelsi, R. Morro, A. Sgambelluri, G. Kanakis, G. Bernini, P. Castoldi, "Dynamic (re) configuration of optical networks based on monitoring information: field trial", Photonic Networks and Devices Conference, 2019.

[C57] K. Kontodimas, K. Christodoulopoulos, E. Zahavi, E. Varvarigos, "Resource allocation in slotted optical data center networks", International Conference on Optical Network Design and Modeling (ONDM), 2018.

[C56] I. Patronas, N. Gkatzios, V. Kitsakis, D. Reisis, K. Christodoulopoulos, E. Varvarigos, "Scheduler Accelerator for TDMA Data Centers", Parallel, Distributed and Network-based Processing Conference (PDP), 2018.

[C55] N. Sambo, K. Christodoulopoulos, N. Argyris, P. Giardina, C. Delezoide, A. Sgambelluri, A. Kretsis, G. Kanakis, F. Fresi, G. Bernini, H. Avramopoulos, E. Varvarigos, P. Castoldi "Experimental demonstration of fully disaggregated white box including different types of transponders and monitors, controlled by NETCONF and YANG", Optical Fiber Communication Conference (OFC), M4A. 3, 2018.

[C54] K. Christodoulopoulos, N. Sambo, N. Argyris, P. Giardina, G. Kanakis, A. Kretsis, F. Fresi, A. Sgambelluri, G. Bernini, C. Delezoide, F. Cugini, H. Avramopoulos, E. Varvarigos, "Observe-Decide-Act: Experimental Demonstration of a Self-Healing Network", Optical Fiber Communication Conference (OFC), M3A. 7, 2018.

[C53] G. Landi, M. Capitani, A. Kretsis, P. Kokkinos, K. Christodoulopoulos, E. Varvarigos "Joint Intra-and Inter-Datacenter Network Optimization and Orchestration", Optical Fiber Communication Conference (OFC), Th2A.34, 2018.

[C52] P. Bakopoulos, K. Tokas, C. Spatharakis, I. Patronas, G. Landi, K. Christodoulopoulos, M. Capitani, A. Kyriakos, M. Aziz, D. Reisis, E. Varvarigos, E. Zahavi, H. Avramopoulos, "Optical datacenter network employing slotted (TDMA) operation for dynamic resource allocation", Optical Interconnects, 2018.

[C51] N .Sambo, P. Giardina, I. Sartzetakis, A. Sgambelluri, F. Fresi, M. Dallaglio, G. Meloni, G. Bernini, K. Christodoulopoulos, P. Castoldi, E. Varvarigos, "Experimental demonstration of network automation based on QoT estimation and monitoring in both single-and multidomains", European Conference and Exhibition on Optical Communications (ECOC), 2017.

[C50] I. Sartzetakis, K. Christodoulopoulos, E. Varvarigos, "On reducing optical monitoring uncertainties and localizing soft failures", IEEE International Conference on Communications (ICC), 2017

[C49] P. Papanikolaou, K. Christodoulopoulos, E. Varvarigos, "Incremental planning of multi-layer elastic optical networks", International ConferenceOptical Network Design and Modeling (ONDM), 2017

[C48] G. Landi, M. Capitani, K. Christodoulopoulos, D. Gallico, M. Biancani, M. Aziz, "An Application-Aware SDN Controller for Hybrid Optical-Electrical DC Networks", ICN 2017

[C47] I. Sartzetakis, K. Christodoulopoulos, E. Varvarigos, "QoT aware adaptive elastic optical networks", Optical Fiber Communication Conference (OFC), 2017.

[C46] G Landi, I Patronas, K Kontodimas, M Aziz, K Christodoulopoulos, A. Kyriakos, M. Capitani, A. F. Hamedani, D. Reisis, E. Varvarigos, P. Bakopoulos, H. Avramopoulos, "SDN control framework with dynamic resource assignment for slotted optical datacenter networks", Optical Fiber Communications Conference (OFC), 2017

[C45] P Soumplis, K Christodoulopoulos, M Quagliotti, A Pagano, E Varvarigos, "Actual margins algorithm for multi-period planning", Optical Fiber Communication Conference (OFC), 2017

[C44] M. Aziz, H.A. Fazely, G. Landi, D. Gallico, K. Christodoulopoulos, P. Wieder, "SDN-enabled application-aware networking for data center networks", IEEE International Conference on Electronics, Circuits and Systems (ICECS), 2016.

[C43] K Christodoulopoulos, K Kontodimas, A Siokis, K Yiannopoulos, E. Varvarigos, "Collisions free scheduling in the NEPHELE hybrid electrical/optical datacenter interconnect", IEEE International Conference on Electronics, Circuits and Systems (ICECS), 2016.

[C42] I Gravalos, P Makris, K Christodoulopoulos, EA Varvarigos, "Efficient Gateways Placement for Internet of Things with QoS Constraints", IEEE Global Communications Conference (GLOBECOM), 2016.

[C41] P. Papanikolaou, K. Christodoulopoulos, E. Varvarigos, “Joint Multilayer Planning of Survivable Elastic Optical Networks”, Optical Fiber Communication Conference (OFC), M2K. 3, 2016.

[C40] K. Christodoulopoulos, N. Sambo, E. Varvarigos, “Exploiting Network Kriging for Fault Localization”, Optical Fiber Communication Conference (OFC), W1B. 5, 2016

[C39] I. Sartzetakis, K. Christodoulopoulos, C. Tsekrekos, D. Syvridis, E. Varvarigos, “Estimating QoT of Unestablished Lightpaths”, Optical Fiber Communication Conference (OFC), Tu3F. 2, 2016

[C38] A. Di Giglio, A. Pagano, K. Christodoulopoulos, P. Kokkinos, N. Argyris, C. Spatharakis, S. Dris, H. Avramopoulos, J-C. Antona, C. Delezoide, P. Jenneve, J. Pesic, Y. Pointurier, P. Castoldi, N. Sambo, G. Bernini, G. Carrozzo, E. Varvarigos, “Cross-layer, dynamic network orchestration, leveraging software-defined optical performance monitors”, AEIT Italian Conference on Photonics Technologies (Fotonica), 2015

[C37] P. Papanikolaou, K. Christodoulopoulos, E. Varvarigos, "Multilayer flex-grid network planning", International Conference on Optical Network Design and Modeling, (ONDM), 2015.

[C36] J.M. Fabrega, M. Moreolo, J.J. Vilchez, K. Christodoulopoulos, E. Varvarigos, J.P. Fernandez-Palacios, "Experimental validation of MTU-BRAS connectivity with DMT transmission and coherent detection in flexgrid metro networks using sliceable transceivers", Optical Fiber Communication conference (OFC), 2015.

[C35] S. Markou, A. Siokis, P. Maniotis, K. Christodoulopoulos, E. Varvarigos, N. Pleros, "Performance analysis and layout design of optical blades for HPCs using the OptoBoard-Sim simulator", IEEE Optical Interconnects (OI), 2015.

[C34] V. Gkamas, K. Christodoulopoulos, E. Varvarigos, "Energy-Aware Multi-layer Flexible Optical Network Operation", International Conference on Software, Telecommunications and Computer Networks (SoftCOM), 2015.

[C33] P. Soumplis, K. Christodoulopoulos, E. Varvarigos, "Dynamic connection establishment and network re-optimization in flexible optical networks",International Conference on Optical Network Design and Modeling (ONDM), 2014.

[C32] P. Soumplis, P. Papanikolaou, K. Christodoulopoulos, G. Papadimitriou, E. Varvarigos, "Energy minimization design of fixed-and flex-grid optical networks", Computer Aided Modeling and Design of Communication Links and Networks (CAMAD), 2014.

[C31] K. Yiannopoulos, E. Varvarigos, V. Katopodis, K. Christodoulopoulos, I. Lazarou, P. Bakopoulos, H. Avramopoulos, D. Klonidis, I. Tomkos, P. Dimos, G. Heliotis, "Coverage capabilities of a multi-wavelength passive optical network architecture", Computer Aided Modeling and Design of Communication Links and Networks (CAMAD), 2014.

[C30] A. Siokis, K. Christodoulopoulos, E. Varvarigos, "Laying out interconnects on optical printed circuit boards", ACM/IEEE symposium on Architectures for networking and communications systems (ANCS), 2014.

[C29] M. S. Moreolo, J.M. Fabrega, F.J. Vilchez, K Christodoulopoulos, E. Varvarigos, V. Lopez, J.P. Fernandez-Palacios, "Assessment of Flexgrid Technologies in the MAN for Centralized BRAS Architecture Using S-BVT", European Conference on Optical Communication (ECOC), 2014

[C28] C. Papageorgiou, K. Christodoulopoulos, N. Doulamis, E. Varvarigos, "On Least Expected Transmissions multicasting in wireless networks", International Conference on Computing, Networking and Communications (ICNC), 2014

[C27] D. Lugones, K. Christodoulopoulos, K. Katrinis, M. Ruffini, D. O Mahony, M. Collier, "Accelerating communication-intensive parallel workloads using commodity optical switches and a software-configurable control stack", European Conference on Parallel and Distributed Computing (Europar), 2013.

[C26] E. Palkopoulou, I. Stiakogiannakis,D. Klonidis, K. Christodoulopoulos, E. Varvarigos, O. Gerstel, I. Tomkos, "Dynamic Cooperative Spectrum Sharing in Elastic Networks", Optical Fiber Communications Conference (OFC), 2013.

[C25] K. Christodoulopoulos, P. Soumplis, E. Varvarigos, "Trading off Transponders for Spectrum in Flexgrid Networks", Optical Fiber Communications Conference (OFC), 2013.

[C24] K. Christodoulopoulos, K. Katrinis, M. Ruffini, D O Mahony, "Topology Configuration in Hybrid EPS/OCS Interconnects", European Conference on Parallel and Distributed Computing (Europar), 2012.

[C23] K. Christodoulopoulos, E. Varvarigos, "Routing and Spectrum Allocation Policies for Time-Varying Traffic in Flexible Optical Networks", International Conference on Optical Networking Design and Modeling (ONDM), 2012.

[C22] M. Angelou, K. Christodoulopoulos, D. Klonidis, A. Klekamp, F. Buchali, E. Varvarigos, I. Tomkos, "Spectrum, Cost and Energy Efficiency in Fixed-Grid and Flex-Grid Networks", Optical Fiber Communications Conference (OFC) 2012.

[C21] K. Christodoulopoulos, I. Tomkos, E. Varvarigos, "Dynamic Bandwidth Allocation in Flexible OFDM-based Networks", Optical Fiber Communications Conference (OFC), 2011.

[C20] K. Christodoulopoulos, K. Manousakis, E. Varvarigos, "Adapting the Transmission Reach in Mixed Line Rates WDM Transport Networks", International Conference on Optical Network Design and Modeling, (ONDM), 2011.

[C19] K. Christodoulopoulos, I. Tomkos, E. Varvarigos, "Routing and Spectrum Allocation in OFDM-based Optical Networks with Elastic Bandwidth Allocation", IEEE Global Conference on Communications (GLOBECOM), 2010.

[C18] K. Christodoulopoulos, I. Tomkos, E. Varvarigos, "Spectrally/Bitrate Flexible Optical Network Planning", European Conference on Optical Communication (ECOC), 2010.

[C17]De Groote, K. Manousakis, P. Kokkinos, D. Colle, M. Pickavet,K. Christodoulopoulos, E. Varvarigos, P. Demeester, "Cost comparison of different Translucent Optical Network Architectures", Conference of Telecommunication, Media and Internet Techno-Economics (CTTE),2010.

[C16] P. Kokkinos, K. Christodoulopoulos, K. Manousakis, E. Varvarigos, "Multi-Parametric Online RWA based on Impairment Generating Sources", IEEE Global Conference on Communications (GLOBECOM), Honolulu, USA, Dec. 2009.

[C15] K. Christodoulopoulos, K. Manousakis, M. Angelou, I. Tomkos, E. Varvarigos, "A Multicost Approach to Online Impairment-Aware RWA", IEEE International Conference on Communications (ICC), Dresden, Germany, June 2009.

[C14] K. Christodoulopoulos, K. Manousakis, E Varvarigos, "Cross-layer Optimization of Static Lightpath Demands in Transparent WDM Optical Networks", IEEE Information Theory Workshop (ITW), Volos, Greece, May 2009.

[C13] K. Manousakis, K. Christodoulopoulos, E. Varvarigos, "Impairment-Aware Offline RWA for Transparent Optical Networks", IEEE Conference on Computer Communications (INFOCOM), Rio De Janeiro, Brazil, April 2009.

[C12] K. Christodoulopoulos, K. Manousakis, E. Varvarigos, "Comparison of Routing and Wavelength Assignment Algorithms in WDM Networks", IEEE Global Telecommunications Conference (GLOBECOM), New Orleans, USA, Dec. 2008.

[C11] E. Varvarigos, V. Sourlas, K. Christodoulopoulos, "Routing and Scheduling Sessions in Networks that Support Advance Reservations", International Conference on Broadband Communications, Networks and Systems (BROADNETS), London, U.K., Sept. 2008.

[C10] K. Christodoulopoulos, N. Doulamis, E. Varvarigos, "Joint Communication and Computation Task Scheduling in Grids", IEEE/ACM International Symposium on Cluster Computing and the Grid (CCGrid), Lyon, France, May 2008.

[C9] P. Kokkinos, K. Christodoulopoulos, A. Kretsis, E. Varvarigos, "Data Consolidation: A Task Scheduling and Data Migration Technique for Grid Networks", IEEE/ACM International Symposium on Cluster Computing and the Grid (CCGrid), Lyon, France, May 2008.

[C8] K. Christodoulopoulos, E. Varvarigos, C. Develder,M. Leenheer, B. Dhoedt, "Job Demand Models For Optical Grid Research", International Conference on Optical Networking Design and Modeling (ONDM),Athens, Greece, May 2007.

[C7] K. Christodoulopoulos, V. Gkamas, E. Varvarigos, "Delay Components of Job Processing in a Grid: Statistical Analysis and Modeling", International Conference on Networking and Services (ICNS), Athens, Greece, 2007.

[C6] M. Oikonomakos, K. Christodoulopoulos, E. Varvarigos, "Profiling Computation Jobs in Grid Systems", IEEE/ACM International Symposium on Cluster Computing and the Grid (CCGrid), Rio De Janeiro, Brazil, May 2007.

[C5] K. Christodoulopoulos, K. Vlachos, K. Yiannopoulos, E. Varvarigos, "Relaxing Delayed Reservations: An approach for QoS provision and service differentiation in Optical Burst Switching networks", International Conference on Broadband Communications, Networks and Systems (BROADNETS), San Jose, USA, Oct. 2006.

[C4] K. Ramantas, K. Christodoulopoulos, K. Vlachos, E. Van Breusegem, M. Pickavet, "SLIP-N Architecture: A new Hybrid Optical Switching Scheme", International Conference on Broadband Communications, Networks and Systems (BROADNETS), San Jose, USA, Oct. 2006.

[C3] K. Christodoulopoulos, E. V. Breusegem, K. Vlachos, M. Pickavet, E. Varvarigos, D. Colle, "Performance Evaluation of Overspill Routing in Optical Networks", IEEE International Conference on Communications (ICC), Istanbul, Turkey, June 2006.

[C2]L. Stampoulidis, E. Kehayas, K. Vyrsokinos, K. Christodoulopoulos, D. Tsiokos, Bakopoulos, T. Kanellos, K. Vlachos, E. A. Varvarigos and H. Avramopoulos, "ARTEMIS: A 40 Gb/s All-Optical Self-Routing Node and Network Architecture employing Asynchronous Bit and Packet-Level Optical Signal Processing", IEEE Global Telecommunications Conference (GLOBECOM), St. Louis, USA, Dec. 2005.

[C1] K. Vyrsokinos, E Kehayas,L. Stampoulidis, H. Avramopoulos, K. Christodoulopoulos, K. Vlachos, E. A. Varvarigos, "ARTEMIS: A New Architecture for All-Optical Asynchronous Self-Routing Network with Efficient Contention Protection and QoS Differentiation", European Conference on Optical Communication (ECOC), Glasgow, U.K., Tech. Dig. We4.P.083, 2005.

Posters

[P8] K. Christodoulopoulos, P. Soumplis, I. Sartzetakis, M. Quagliotti, A. Di Giglio, A. Pagano, N. Argyris, C. Spatharakis, S. Dris, H. Avramopoulos, JC. Antona, C. Delezoide, P. Jennevé, J. Pesic, Y. Pointurier, N. Sambo, F. Cugini, P. Castoldi, G. Bernini, F. Moscatelli ,G. Carrozzo, E. Varvarigos, " ORCHESTRA- Optical performance monitoring enabling flexible networking", European Conference on Networks and Communications (EuCNC), 2016.

[P7] N Sambo, K Christodoulopoulos, P Castoldi, E Varvarigos, " Spectrum sharing for elastic transmission parameter adaptation", European Conference on Optical Communication (ECOC), 2016.

[P6] V. Gkamas, K. Christodoulopoulos, E. Varvarigos, "A comparison study of joint and sequential multi-layer planning for IP over flexible optical networks", Optical Fiber Communications Conference (OFC), 2015.

[P5] K. Christodoulopoulos, K. Katrinis, M. Ruffini, D. O'Mahony, "Accelerating HPC workloads with dynamic adaptation of a software-defined hybrid electronic/optical interconnect", Optical Fiber Communication Conference (OFC), 2014.

[P4] K. Christodoulopoulos, M. Angelou, P. Zakynthinos, D. Klonidis, E. Varvarigos, I. Tomkos, "The Value of Flexible Optical Networking, poster", ECOC, 2011

[P3] K. Manousakis, K. Christodoulopoulos, E. Varvarigos, "Avoiding Adjacent Channel Interference in Static RWA", 6th International Symposium on communication systems, networks and digital signal processing (CSNDSP) Graz, Austria, 2008.

[P2] K. Christodoulopoulos, N. Doulamis, E.Varvarigos "Joint Communication and Computation Task Scheduling in Grids", 3rd E-science Conference, 2007. (Best poster award).

[P1] K. Christodoulopoulos, E. Varvarigos "Statistical Analysis of the Workload and Modeling of the Time a Job Spends at Different States in the LCG/EGEE Environment", EGEE Conference, 2007.

Invited Talks

[I22] K. Christodoulopoulos, K. Kontodimas, L. Dembeck, E. Varvarigos, "Slotted Optical Datacenter Networks with Sub-Wavelength Resource Allocation", Optical Fiber Communication Conference (OFC), 2018.

[I21] K. Christodoulopoulos, I. Sartzetakis, P. Soumplis, E. Varvarigos, "Machine Learning Assisted Quality of Transmission Estimation and Planning with Reduced Margins", International Conference onOptical Network Design and Modeling (ONDM), 2019.

[I20] C. Delezoide, K. Christodoulopoulos, A. Kretsis, N. Argyris, G. Kanakis, A. Sgambelluri, N. Sambo, P. Giardina, G. Bernini, D. Roccato, A. Percelsi, R. Morro, H Avramopoulos, E Varvarigos, P Castoldi, P Layec, S Bigo, "Pre-emptive detection and localization of failures towards marginless operations of optical networks", International Conference on Transparent Optical Networks (ICTON), 2018.

[I19] A. Kretsis, P. Soumplis, K. Christodoulopoulos, E. Varvarigos, "DEPLOY Tool: Incrementally Planning Marginless Elastic Optical Networks", International Conference on Transparent Optical Networks (ICTON), 2018.

[I18] K. Christodoulopoulos, I. Sartzetakis, P. Soumplis, E. Varvarigos, "Cross-layer and dynamic network orchestration based on optical performance monitoring", International Conference onOptical Network Design and Modeling (ONDM), 2017.

[I17] I Sartzetakis, K Christodoulopoulos, E Varvarigos, "Improving QoT estimation accuracy through active monitoring", International Conference on Transparent Optical Networks (ICTON), 2017

[I16] K. Yiannopoulos, K. Kontodimas, K. Christodoulopoulos, E. Varvarigos, "Resource partitioning in the NEPHELE datacentre interconnect", International Conference on Transparent Optical Networks (ICTON), 2017.

[I15] A. Kretsis, L. Corazza, K. Christodoulopoulos, P. Kokkinos, E. Varvarigos, “An emulation environment for SDN enabled flexible IP/optical networks”, International Conference on Transparent Optical Networks (ICTON), 2016

[I14] K. Christodoulopoulos, K. Kontodimas, K. Yiannopoulos, E. Varvarigos, “Bandwidth allocation in the NEPHELE hybrid optical interconnect”, International Conference on Transparent Optical Networks (ICTON), 2016

[I13] K. Christodoulopoulos, E. Varvarigos, "Evaluating flexibility degrees in optical networks", Optical Fiber Communication Conference (OFC), 2015.

[I12] K. Christodoulopoulos, P. Kokkinos, A. Di Giglio, A. Pagano, N. Argyris, C. Spatharakis, S. Dris, H. Avramopoulos, JC. Antona, C. Delezoide, P. Jenneve, J. Pesic, Y. Pointurier, N. Sambo, F. Cugini, P. Castoldi, G. Bernini , G. Carrozzo, and E. Varvarigos, "ORCHESTRA - Optical performance monitoring enabling flexible networking", International Conference on Transparent Optical Networks (ICTON), 2015.

[I11] P. Castoldi, G. Bernini, K. Christodoulopoulos, F. Cugini, N. Sambo, “A monitoring architecture for self-configurable optical networks”, ”, International Conference on Transparent Optical Networks (ICTON), 2015

[I10] P. Soumplis, P. Papanikolaou, K. Christodoulopoulos, N. Argyris, C. Spatharakis, S. Dris, H. Avramopoulos, E. Varvarigos, "Cross-layer optimization: Network cost vs. physical layer margins", International Conference on Transparent Optical Networks (ICTON), 2015.

[I9] E. Varvarigos, K. Christodoulopoulos, "Algorithmic challenges in flexible optical networks", International Conference on Computing, Networking and Communications (ICNC), 2014.

[I8] A. Siokis, K. Christodoulopoulos, E. Varvarigos, "On-OPCB interconnection networks", International Conference on Transparent Optical Networks (ICTON), 2014.

[I7] A. Kretsis, P. Kokkinos, K. Christodoulopoulos, E. Varvarigos, "Mantis: Optical network planning and operation tool", International Conference on Transparent Optical Networks (ICTON), 2013.

[I6] E. Varvarigos, K. Christodoulopoulos, Static and dynamic spectrum allocation in flexi-grid optical networks", International Conference on Transparent Optical Networks, (ICTON), 2012.

[I5] E. Varvarigos, K. Christodoulopoulos, "Algorithmic aspects of optical network design", International Conference on Optical Network Design and Modeling, (ONDM), 2011.

[I4] K. Christodoulopoulos, "Elastic Bandwidth Allocation in Flexible OFDM-based Optical Networks", Workshop on Cross-layer Algorithms and Protocols for Optical Networks, International Conference on Broadband Communications, Networks and Systems (BROADNETS), Athens, Greece, Oct. 2010.

[I3] K. Christodoulopoulos, P. Kokkinos, K. Manousakis, E. Varvarigos, " Cross Layer RWA in WDM Networks: Is the Added Complexity Useful or a Burden?, International Conference on Transparent Optical Networks, (ICTON), Azores, Portugal, July 2009.

[I2] K. Christodoulopoulos, I. Tomkos, E. Varvarigos, "A Comparison of Offline IARWA Approaches", Networks and Optical Communications - Optical Cabling and Infrastructure (NOC-OCI), Valladolid, Spain, June 2009.

[I1] K. Christodoulopoulos, E. Varvarigos, "Routing and Scheduling in Grids", International Conference on Transparent Optical Networks, (

Book Chapters

[B6] A. Siokis, K. Christodoulopoulos, E. Varvarigos, "The role of optical interconnects in the design of data center architectures", Elsevier Optical Interconnects for Data Centers, pp 375-393, 2017.

[B5] L. Velasco, M. Ruiz, K. Christodoulopoulos, E. Varvarigos, M. Zotkiewicz, M. Pioro, “Routing and Spectrum Allocation”, Elastic Optical Networks, pp. 55-81, 2016.

[B4] A. Stavdas, C. Matrakidis, M. Gunkel, A. Asensio, L. Velasco, E. Varvarigos, K. Christodoulopoulos “Taking Advantage of Elastic Optical Networks”, Elastic Optical Networks, pp. 31-54, 2016.

[B3] K. Christodoulopoulos, E. Varvarigos, "Considering linear and non-linear impairments in offline-design", in "Cross-layer Design in Optical Networks",Eds Subramaniam,Chava, Springer, to appear.

[B2] K. Christodoulopoulos, E. Varvarigos, "Online Impairment Aware Routing and Wavelength Assignment in WDM Optical Networks", in "Horizons in Computer Science Research. Volume 6", Nova publishers, 2011, ISBN:978-1-61470-455-3.

[B1] P. Kokkinos, K. Christodoulopoulos, N. Doulamis, E. Varvarigos, "Quality of Service Scheduling of Computation and Communication Resources in Grid Networks", Chapter 3, Grid Computing Research Progress, Nova publishers, 2008. ISBN: 978-1-60456-404-4.

Teaching

Adjunct Assistant Professor, Computer Engineering and Informatics Department (CEID), University of Patras, Greece

2009-2010, Spring term, Mirco-Computers 2 (micro2).
2010-2011, Autumn term, Computer Networks Laboratory (netlab).
2010-2011, Autumn term, Micro-Computers Laboratory.

Extracurricular Activities

Movies
Music
Sports