Tor Skeie

• Sæternes, Erik Hide; Thune, Andreas; Rustad, Alf Birger; Skeie, Tor & Cai, Xing (2024). Automated parameter tuning with accuracy control for efficient reservoir simulations. Journal of Computational Science. ISSN 1877-7503. 75. doi: 10.1016/j.jocs.2023.102205. Fulltekst i vitenarkiv
• Thune, Andreas; Reinemo, Sven- Arne; Skeie, Tor & Cai, Xing (2023). Detailed modeling of heterogeneous and contention-constrained point-to-point MPI communication. IEEE Transactions on Parallel and Distributed Systems. ISSN 1045-9219. 34(5), s. 1580–1593. doi: 10.1109/TPDS.2023.3253881.
• Teigen, Bjørn Ivar; Davies, Neil; Thompson, Peter; Ellefsen, Kai Olav; Skeie, Tor & Tørresen, Jim (2022). ΔQ Generative Models: Modeling Time-Variation in Network Quality, Proceedings of the 2022 18th International Conference of Network and Service Management. IEEE (Institute of Electrical and Electronics Engineers). ISSN 978-3-903176-51-5. s. 233–239. doi: 10.23919/CNSM55787.2022.9965128.
• Teigen, Bjørn Ivar; Davies, Neil; Ellefsen, Kai Olav; Skeie, Tor & Tørresen, Jim (2022). Quantifying the Quality Attenuation of WiFi, Proceedings of the 47th IEEE Conference on Local Computer Networks . IEEE (Institute of Electrical and Electronics Engineers). ISSN 978-1-6654-8001-7. s. 189–197. doi: 10.1109/LCN53696.2022.9843690.
• Teigen, Bjørn Ivar; Davies, Neil; Ellefsen, Kai Olav; Skeie, Tor & Tørresen, Jim (2022). Protocol Violations in the WiFi Distributed Coordination Function of Raspberry Pi 4, 2022 17th Wireless On-Demand Network Systems and Services Conference (WONS). IEEE (Institute of Electrical and Electronics Engineers). ISSN 978-3-903176-46-1. doi: 10.23919/WONS54113.2022.9764440.
• Rocher-González, José; Gran, Ernst Gunnar; Reinemo, Sven- Arne; Skeie, Tor; Escudero-Sahuquillo, Jesús & Garcia, Pedro J. [Vis alle 7 forfattere av denne artikkelen] (2022). Adaptive Routing in InfiniBand Hardware. I Fazio, Maria; Panda, Dhabaleswar K.; Prodan, Radu; Cardellini, Valeria; Kantarci, Burak; Rana, Omer & Villari, Massimo (Red.), Proceedings of the 22nd IEEE International Symposium on Cluster, Cloud and Internet Computing (CCGrid 2022). IEEE conference proceedings. ISSN 978-1-6654-9957-6. s. 463–472. doi: 10.1109/CCGrid54584.2022.00056. Fulltekst i vitenarkiv Vis sammendrag

  Interconnection networks are the communication backbone of modern high-performance computing systems and an optimised interconnection network is crucial for the performance and utilisation of the system as a whole. One element of the interconnection network is the routing algorithm, which directly influences how we are able to utilise the physical network topology. InfiniBand is one of the most common network architectures used in high-performance computing and traditionally it only supported static routing. For multi-path networks such as Fat-trees, static routing is inefficient because it cannot balance traffic in real-time nor utilise multiple paths efficiently under adversarial traffic. This again potentially leads to unnecessary contention and an underutilised network, which has led to numerous proposals on how to avoid this by using adaptive routing. Adaptive routing has recently been introduced in InfiniBand and in this paper we evaluate to what extent the expected benefits of adaptive routing is true for InfiniBand. Through a set of experiments on HDR InfiniBand equipment we describe the basic behaviour of adaptive routing in InfiniBand, its benefits in Fat tree topologies and the unfortunate side effects related to unfairness that adaptive routing in general might introduce, including such phenomena as the reverse parking lot problem and congestion spreading.

• Teigen, Bjørn Ivar; Ellefsen, Kai Olav; Skeie, Tor & Tørresen, Jim (2021). Known Performance Issues Are Prevalent in Consumer WiFi Routers, 17th International Conference on Network and Service Management, CNSM 2021. IEEE (Institute of Electrical and Electronics Engineers). ISSN 978-3-903176-36-2. s. 254–258. doi: 10.23919/CNSM52442.2021.9615514.
• Tasoulas, Evangelos; Zahid, Feroz; Gran, Ernst Gunnar; Begnum, Kyrre; Johnsen, Bjørn Dag & Skeie, Tor (2019). Efficient routing and reconfiguration in virtualized HPC environments with vSwitch-enabled lossless networks. Concurrency and Computation. ISSN 1532-0626. 31(2). doi: 10.1002/cpe.4443. Fulltekst i vitenarkiv
• Zahid, Feroz; Taherkordi, Amirhosein; Gran, Ernst Gunnar; Skeie, Tor & Johnsen, Bjørn Dag (2018). A Self-Adaptive Network for HPC Clouds: Architecture, Framework, and Implementation. IEEE Transactions on Parallel and Distributed Systems. ISSN 1045-9219. 29(12), s. 2658–2671. doi: 10.1109/TPDS.2018.2842224. Fulltekst i vitenarkiv
• Abbas, Nasir; Zhang, Yan; Taherkordi, Amirhosein & Skeie, Tor (2017). Mobile Edge Computing: A Survey. IEEE Internet of Things Journal. ISSN 2327-4662. 5(1), s. 450–465. doi: 10.1109/JIOT.2017.2750180.
• Peñaranda, Roberto; Lopez, Pedro; Gómez, Maria E.; Gran, Ernst Gunnar & Skeie, Tor (2017). A Fault-Tolerant Routing Strategy for K-ary N-direct S-indirect Topologies Based on Intermediate Nodes. Concurrency and Computation. ISSN 1532-0626. 29(13). doi: 10.1002/cpe.4065. Fulltekst i vitenarkiv
• Zahid, Feroz; Gran, Ernst Gunnar; Bogdanski, Bartosz; Johnsen, Bjørn Dag & Skeie, Tor (2017). Efficient network isolation and load balancing in multi-tenant HPC clusters . Future Generation Computer Systems. ISSN 0167-739X. 72, s. 145–162. doi: 10.1016/j.future.2016.04.003. Fulltekst i vitenarkiv
• Pham, Hai Ngoc; Zhang, Yan; Skeie, Tor; Engelstad, Paal E. & Eliassen, Frank (2016). Joint energy-efficient cooperative spectrum sensing and power allocation in Cognitive Machine-to-Machine Communications, Proceedings of the 2016 International Wireless Communications and Mobile Computing Conference (IWCMC 2016). IEEE (Institute of Electrical and Electronics Engineers). ISSN 978-1-5090-0304-4. doi: 10.1109/IWCMC.2016.7577208.
• Tasoulas, Evangelos; Gran, Ernst Gunnar; Skeie, Tor & Johnsen, Bjørn Dag (2016). Fast hybrid network reconfiguration for large-scale lossless interconnection networks. I Pellegrini, Alessandro; Gkoulalas-Divanis, Aris; Di Sanzo, Pierangelo & Avresky, Dimiter R. (Red.), 2016 IEEE 15th International Symposium on Network Computing and Applications. IEEE (Institute of Electrical and Electronics Engineers). ISSN 978-1-5090-3216-7. s. 101–108. doi: 10.1109/NCA.2016.7778601.
• Peñaranda, Roberto; Gran, Ernst Gunnar; Skeie, Tor; Engracia Gómez, Maria & Lopez, Pedro (2016). A New Fault-Tolerant Routing Methodology for KNS Topologies. I García, Pedro & Escudero-Sahuquillo, Jesus (Red.), 2nd IEEE International Workshop on High-Performance Interconnection Networks in the Exascale and Big-Data Era (HiPINEB). IEEE (Institute of Electrical and Electronics Engineers). ISSN 978-1-5090-2121-5. s. 1–8. doi: 10.1109/HIPINEB.2016.9.
• Zahid, Feroz; Gran, Ernst Gunnar; Bogdanski, Bartosz Grzegorz; Johnsen, Bjørn Dag; Skeie, Tor & Tasoulas, Evangelos (2016). Compact network reconfiguration in fat-trees. The Journal of Supercomputing. ISSN 0920-8542. 72(12), s. 4438–4467. doi: 10.1007/s11227-016-1759-y.
• Tasoulas, Evangelos; Gran, Ernst Gunnar; Johnsen, Bjørn Dag; Begnum, Kyrre & Skeie, Tor (2015). Towards the InfiniBand SR-IOV vSwitch architecture. Proceedings IEEE International Conference on Cluster Computing. ISSN 1552-5244. 2015-October, s. 371–380. doi: 10.1109/CLUSTER.2015.58. Vis sammendrag

  To meet the demands of the Exascale era and facilitate Big Data analytics in the cloud while maintaining flexibility, cloud providers will have to offer efficient virtualized High Performance Computing clusters in a pay-as-you-go model. As a consequence, high performance network interconnect solutions, like InfiniBand (IB), will be beneficial. Currently, the only way to provide IB connectivity on Virtual Machines (VMs) is by utilizing direct device assignment. At the same time to be scalable, Single-Root I/O Virtualization (SR-IOV) is used. However, the current SR-IOV model employed by IB adapters is a Shared Port implementation with limited flexibility, as it does not allow transparent virtualization and live-migration of VMs. In this paper, we explore an alternative SR-IOV model for IB, the virtual switch (vSwitch), and propose and analyze two vSwitch implementations with different scalability characteristics. Furthermore, as network reconfiguration time is critical to make live-migration a practical option, we accompany our proposed architecture with a scalable and topology agnostic dynamic reconfiguration method, implemented and tested using OpenSM. Our results show that we are able to significantly reduce the reconfiguration time as route recalculations are no longer needed, and in large IB subnets, for certain scenarios, the number of reconfiguration subnet management packets (SMPs) sent is reduced from several hundred thousand down to a single one.

• Zahid, Feroz; Gran, Ernst Gunnar; Bogdanski, Bartosz; Johnsen, Bjørn Dag & Skeie, Tor (2015). SlimUpdate: Minimal Routing Update for Performance-Based Reconfigurations in Fat-Trees. I Escudero-Sahuquillo, Jesús & Javier Garcia, Pedro (Red.), The 1st IEEE International Workshop on High-Performance Interconnection Networks in the Exascale and Big-Data Era (HiPINEB 2015) held in conjunction with IEEE Cluster 2015. IEEE (Institute of Electrical and Electronics Engineers). ISSN 978-1-4673-6598-7. s. 849–856. doi: 10.1109/CLUSTER.2015.142. Vis sammendrag

  As the size of high-performance computing systems grows, the number of events requiring a network reconfiguration, as well as the complexity of each reconfiguration, is likely to increase. In large systems, the probability of component failure is high. At the same time, with more network components, ensuring high utilization of network resources becomes challenging. Reconfiguration in interconnection networks, like InfiniBand (IB), typically involves computation and distribution of a new set of routes in order to maintain connectivity and performance. In general, current routing algorithms do not consider the existing routes in a network when calculating new ones. Such configuration-oblivious routing might result in substantial modifications to the existing paths, and the reconfiguration becomes costly as it potentially involves a large number of source-destination pairs. In this paper, we propose a novel routing algorithm for IB based fat-tree topologies, SlimUpdate. SlimUpdate employs techniques to preserve existing forwarding entries in switches to ensure a minimal routing update, without any performance penalty, and with minimal computational overhead. We present an implementation of SlimUpdate in OpenSM, and compare it with the current de facto fat-tree routing algorithm. Our experiments and simulations show a decrease of up to 80% in the number of total path modifications when using SlimUpdate routing, while achieving similar or even better performance than the fat-tree routing in most reconfiguration scenarios.

• Zahid, Feroz; Gran, Ernst Gunnar; Bogdanski, Bartosz; Johnsen, Bjørn Dag & Skeie, Tor (2015). Partition-aware routing to improve network isolation in InfiniBand based multi-tenant clusters. I Balaji, Pavan & Xu, Cheng-Zhong (Red.), 15th IEEE/ACM International Symposium on Cluster, Cloud and Grid Computing, CCGrid 2015, 2015, Shenzhen, 4-7 May 2015. IEEE (Institute of Electrical and Electronics Engineers). ISSN 978-1-4799-8006-2. s. 189–198. doi: 10.1109/CCGrid.2015.96.
• Zahid, Feroz; Gran, Ernst Gunnar; Bogdanski, Bartosz; Johnsen, Bjørn Dag & Skeie, Tor (2015). A weighted fat-tree routing algorithm for efficient load-balancing in InfiniBand enterprise clusters. I Daneshtalab, Masoud & Brorsson, Mats (Red.), Proceedings of 23rd Euromicro International Conference on Parallel, Distributed, and Network-Based Processing (PDP 2015). IEEE (Institute of Electrical and Electronics Engineers). ISSN 978-1-4799-8490-9. s. 35–42. doi: 10.1109/PDP.2015.111. Vis sammendrag

  InfiniBand (IB) has become a popular network interconnect for high-performance computing (HPC) systems. Many of the large IB-based HPC systems use some variant of the fat-tree topology to take advantage of the useful properties fat-trees offer. The fat-tree routing algorithm is one of the most efficient deterministic routing algorithms for fat-tree topologies. The algorithm ensures that the number of routes assigned to each link are balanced across the fabric. However, one problem with its load-balancing technique is that it assumes uniform traffic distribution in the network. When routes towards nodes that mainly consume large amount of data are assigned to share links in the fabric while alternative links are underutilized, sub-optimal network throughput is obtained. Also, as the fat-tree algorithm routes nodes according to the indexing order, the performance may differ for two systems cabled in the exact same way. In this paper, we propose wFatTree, a novel fat-tree routing algorithm, which considers node traffic characteristics to balance load across the network links more evenly, and with predictable network performance. Our experiments and simulations show an improvement of up to 60% in total network throughput on large fat-tree installations when using wFatTree routing. Furthermore, wFatTree can also be used to prioritize traffic flowing towards the critical nodes in the network.

• Escudero-Sahuquillo, Jesús; Gran, Ernst Gunnar; García, Pedro; Flich, Jose; Skeie, Tor & Lysne, Olav [Vis alle 8 forfattere av denne artikkelen] (2015). Efficient and Cost-Effective Hybrid Congestion Control for HPC Interconnection Networks. IEEE Transactions on Parallel and Distributed Systems. ISSN 1045-9219. 26(1), s. 107–119. doi: 10.1109/TPDS.2014.2307851.
• Escudero-Sahuquillo, Jesús; Garcia, Pedro J.; Quiles, Francisco J.; Reinemo, Sve Arne; Skeie, Tor & Lysne, Olav [Vis alle 7 forfattere av denne artikkelen] (2014). A new proposal to deal with congestion in InfiniBand-based fat-trees. Journal of Parallel and Distributed Computing. ISSN 0743-7315. 74(1), s. 1802–1819. doi: 10.1016/j.jpdc.2013.09.002.
• Sem-Jacobsen, Frank Olaf; Mocholi, Samuel Rodrigo; Strano, A.; Skeie, Tor; Bertozzi, D. & Gilabert, F. (2013). Enabling Power Efficiency through Dynamic Rerouting On-Chip. ACM Transactions on Embedded Computing Systems. ISSN 1539-9087. 12(4). doi: 10.1145/2485984.2485999.
• Sem-Jacobsen, Frank Olaf; Mocholi, Samuel Rodrigo; Skeie, Tor; Strano, A. & Bertozzi, D. (2013). An Efficient, Low-Cost Routing Framework for Convex Mesh Partitions to Support Virtualisation. ACM Transactions on Embedded Computing Systems. ISSN 1539-9087. 12(4). doi: 10.1145/2485984.2485995.
• Escudero-Sahuquillo, Jesús; García, Pedro; Quiles, F. J.; Reinemo, Sve Arne; Skeie, Tor & Lysne, Olav [Vis alle 7 forfattere av denne artikkelen] (2013). A New Proposal to Deal with Congestion in InfiniBand-based Fat-Trees. Journal of Parallel and Distributed Computing. ISSN 0743-7315. 17(1), s. 1802–1819. doi: 10.1016/j.jpdc.2013.09.002.
• Guay, Wei Lin; Reinemo, Sven-Arne; Johnsen, Bjørn Dag; Skeie, Tor & Torudbakken, Ola (2012). A Scalable Signalling Mechanism for VM Migration with SR-IOV over InfiniBand, IEEE International Conference on Parallel and Distributed Systems. IEEE (Institute of Electrical and Electronics Engineers). ISSN 978-0-7695-4903-3. s. 384–391. doi: 10.1109/icpads.2012.60.
• Gran, Ernst Gunnar; Reinemo, Sven-Arne; Lysne, Olav; Skeie, Tor; Zahavi, Eitan & Shainer, Gilad (2012). Exploring the Scope of the InfiniBand Congestion Control Mechanism, IEEE International Parallel & Distributed Processing Symposium. IEEE (Institute of Electrical and Electronics Engineers). ISSN 978-1-4673-0975-2. s. 1131–1143. doi: 10.1109/ipdps.2012.104.
• Rodrigo, Samuel; Sem-Jacobsen, Frank Olaf; Tatenguem, Hervé; Skeie, Tor & Bertozzi, Davide (2012). Cost-effective Contention Avoidance in a CMP with Shared Memory Controllers, Euro-Par 2012 Parallel Processing. Springer. ISSN 978-3-642-32820-6. s. 741–752. doi: 10.1007/978-3-642-32820-6_73.
• Flich, Jose; Skeie, Tor; Mejìa, Andrès; Lysne, Olav; Lopez, Pedro & Robles, Antonio [Vis alle 10 forfattere av denne artikkelen] (2012). A Survey and Evaluation of Topology-Agnostic Deterministic Routing Algorithms. IEEE Transactions on Parallel and Distributed Systems. ISSN 1045-9219. 23(3), s. 405–425. doi: 10.1109/TPDS.2011.190.
• Guay, Wei Lin; Reinemo, Sve Arne; Lysne, Olav & Skeie, Tor (2011). dFtree - A Fat-tree Routing Algorithm using Dynamic Allocation of Virtual Lanes to Alleviate Congestion in InfiniBand Networks. I Balman, Mehmet & Byna, Surendra (Red.), Proceedings of the 2011 International Workshop on Network-aware Data Management (NDM '11). Association for Computing Machinery (ACM). ISSN 978-1-4503-1132-8. s. 1–10. doi: 10.1109/ipdps.2011.28.
• Sem-Jacobsen, Frank Olaf; Mocholi, Samuel Rodrigo & Skeie, Tor (2011). iFDOR - Dynamic Rerouting On-Chip. I Ukjent, U. (Red.), Proceedings of the Fifth International Workshop on Interconnection Network Architecture: On-Chip, Multi-Chip. ACM Publications. ISSN 978-1-4503-0272-2. s. 11–14. doi: 10.1145/1930037.1930041. Vis sammendrag

  Many-core chip design requires flexible routing solutions for the interconnect to handle faults, provide performance partitions, and react to dynamic changes in processing requirements and power/heat distribution. We have developed a logic based rerouting mechanism suitable for tolerating dynamic powering down of regions within the application partition on the chip. This mechanism is combined with the logic based FDOR routing algorithm to create a powerful routing algorithm with low implementation cost. This allows for higher system utilisation through enabling more efficient power management as well as supporting many irregular mesh topologies through flexible virtualisation. Results show that powering down a single switch results in an 8% throughput reduction in the worst case for the evaluated topology.

• Le-Trung, Quan; Engelstad, Paal Einar; Skeie, Tor; Eliassen, Frank & Taherkordi, Amirhosein (2011). Mobility Management for All-IP Mobile Networks. I Makaya, Christian & Pierre, Samuel (Red.), Emerging Wireless Networks - Concepts, Techniques, Applications. Taylor & Francis. ISSN 9781439821350.
• Sem-Jacobsen, Frank Olaf; Skeie, Tor; Lysne, Olav & Duato, José (2011). Dynamic Fault Tolerance in Fat Trees. IEEE transactions on computers. ISSN 0018-9340. 60(4), s. 508–525. doi: 10.1109/TC.2010.97.
• Pham, Hai Ngoc; Zhang, Yan; Engelstad, Paal Einar; Skeie, Tor & Eliassen, Frank (2010). Energy Minimization Approach for Optimal Cooperative Spectrum Sensing in Sensor-Aided Cognitive Radio Networks. I Chen, Hsiao-Hwa & Daneshmand, Mahmoud (Red.), Proceedings of the 2010 The 5th Annual ICST Wireless Internet Conference WICON 2010. Central European University Press. ISSN 978-963-9799-86-8.
• Sem-Jacobsen, Frank Olav; Lysne, Olav; Skeie, Tor & Duanto, Jose (2010). Dynamic Fault Tolerance in Fat-Trees. IEEE transactions on computers. ISSN 0018-9340.
• Xiang, Jie; Zhang, Yan; Skeie, Tor & Xie, Lang (2010). Downlink Spectrum Sharing for Cognitive Radio Femtocell Networks. IEEE Systems Journal. ISSN 1932-8184. 4(4), s. 524–534. doi: 10.1109/JSYST.2010.2083230.
• Lysne, Olav; Skeie, Tor; Reinemo, Svein Arne; Sem-Jacobsen, Frank Olav & Nordbotten, N.A. (2010). Scalable Interconnection Networks. I Tveito, Aslak; Bruaset, Are Magnus & Lysne, Olav (Red.), Simula Research Laboratory - by thinking constantly about it. Springer. ISSN 978-3-642-01155-9. s. 129–162.
• Xiang, J.; Zhang, Y. & Skeie, Tor (2010). Dynamic Spectrum Sharing in Cognitive Radio Femtocell Networks. I Xiao, Jun Hei & Lawrence, Cheung (Red.), 2009 Fourth International Conference on Access Networks (ACCESSNETS 2009). Springer. ISSN 978-3-642-11663-6.
• Xiang, Jie; Zhang, Yan & Skeie, Tor (2010). Medium access control protocols in cognitive radio networks. Wireless Communications & Mobile Computing. ISSN 1530-8669. 10(1), s. 31–49. doi: 10.1002/wcm.906.
• Le Trung, Quan; Engelstad, Paal Einar; Taherkordi, Amirhosein; Skeie, Tor & Pham, Hai Ngoc (2009). Information Storage, Reduction and Dissemination in Sensor Networks: A Survey. I Gibbs, Simon (Red.), 6th Annual IEEE Consumer Communications & Networking Conference IEEE CCNC 2009, Workshop Information Retrieval in Sensor Networks. IEEE Sarnoff Symposium. ISSN 978-1-4244-2309-5. s. 505–510.
• Casado, R.; Bermudez, A.; Robles-Gomez, A.; Lysne, Olav; Skeie, Tor & Solheim, Åshild Grønstad (2009). Network Reconfiguration in High-Performance Interconnection Networks. I Denko, Mieso K.; Yang, Laurence Tianruo & Zhang, Yan (Red.), Autonomic Computing and Networking. Springer. ISSN 978-0-387-89827-8. s. 313–332.
• Le Trung, Quan; Taherkordi, Amirhosein; Eliassen, Frank; Pham, Hai Ngoc; Skeie, Tor & Engelstad, Paal Einar (2009). DCM-Arch: An Architecture for Data, Control, and Management in Wireless Sensor Networks. I Awan, Irfan; Younas, Muhammad; Hara, Takahiro & Durresi, Arjan (Red.), The IEEE 23rd International Conference on Advanced Information Networking and Applications, AINA 2009, Bradford, United Kingdom, May 26-29, 2009. IEEE (Institute of Electrical and Electronics Engineers). ISSN 978-0-7695-3638-5. s. 898–905.
• Pham, Hai Ngoc; Zhang, Y.; Engelstad, Paal Einar; Skeie, Tor & Eliassen, Frank (2009). Optimal Cooperative Spectrum Sensing in Cognitive Sensor Networks. I IWCMC, IWCMC (Red.), The 5th International Wireless Communications and Mobile Computing Conference (IWCMC '09). ACM Publications. ISSN 978-1-60558-569-7. s. 1073–1079.
• Skeie, Tor; Sem-Jacobsen, Frank Olaf; Rodrigo, S.; Flich, J.; Bertozzi, D. & Simone, M. (2009). Flexible DOR Routing for Virtualization of Multicore Chips. I IEEE, IEEE (Red.), System-on-Chip, 2009. SOC 2009. International Symposium on. IEEE conference proceedings. ISSN 978-1-4244-4465-6. s. 73–76.
• Solheim, Åshild Grønstad; Lysne, Olav & Skeie, Tor (2009). RecTOR: A New and Efficient Method for Dynamic Network Reconfiguration. I Sips, H.; Epema, D. & Lin, H.-X. (Red.), Euro-Par 2009. Springer. ISSN 978-3-642-03868-6. s. 1052–1064.
• Robles-Gomez, A; Bermudez, A; Casado, R; Solheim, Åshild Grønstad; Sødring, T. & Skeie, Tor (2009). A new distributed management mechanism for ASI based networks. Computer Communications. ISSN 0140-3664. 32(2), s. 294–304. doi: 10.1016/j.comcom.2008.10.010.
• Le-Trung, Quan; Engelstad, Paal Einar; Pham, Vinh; Skeie, Tor; Taherkordi, Amirhosein & Eliassen, Frank (2009). Providing internet connectivity and mobility management for MANETs. International Journal of Web Information Systems. ISSN 1744-0084. 5(2), s. 239–263. doi: 10.1108/17440080910968472.
• Xiang, Jie; Zhang, Y; Skeie, Tor & He, J (2009). QoS Aware Admission and Power Control for Cognitive Radio Cellular Networks. Wireless Communications & Mobile Computing. ISSN 1530-8669. 9(11), s. 1520–1531. doi: 10.1002/wcm.765.
• Nordbotten, Nils & Skeie, Tor (2008). A Routing Methodology for Dynamic Fault Tolerance in Meshes and Tori. I Aluru, Srinivas; Parashar, Manish; Badrinath, Ramamurthy & Prasanna, Viktor K. (Red.), High Performance Computing - HiPC 2007: 14th International Conference. Springer. ISSN 978-3540772194. s. 514–527.
• Le Trung, Quan; Engelstad, Paal Einar; Skeie, Tor & Taherkordi, Amirhosein (2008). Load-Balance of Intra/Inter-MANET Traffic over Multiple Internet Gateways. I Kotsis, Gabriele (Red.), The 6th International Conference on Advances in Mobile Computing & Multimedia (MoMM2008). Association for Computing Machinery (ACM). ISSN 978-1-60558-269-6. s. 50–57.
• Flich, Jose; Duarto, J; Sødring, T.; Solheim, Åshild Grønstad; Skeie, Tor & Lysne, Olav (2008). On the Potential of NoC Virtualization for Multicore Chips. I Paliana, Sabri (Red.), Complex, Intelligent and Software Intensive Systems. IEEE Press. ISSN 978-0-7695-3109-0. s. 801–807.
• Sem-Jacobsen, Frank Olaf & Skeie, Tor (2008). Maintaining Quality of Service with Dynamic Fault Tolerance in Fat Trees. I Sadayappan, Ponnuswamy (Red.), High Performance Computing - HiPC 2008, 15th International Conference. Springer. ISSN 978-3-540-89893-1. s. 451–464.
• Sødring, T.; Solheim, Åshild Grønstad; Skeie, Tor & Reinemo, Svein- Arne (2008). An Analysis of Connectivity and Yield for 2D Mesh Based NoC with Interconnect Router Failures. I Fanucci, Luca (Red.), 11th EUROMICRO Conference on Digital System Design (DSD). University of Parma. ISSN 978-0-7695-3277-6.
• Xiang, Jie; Zhang, Y. & Skeie, Tor (2008). Joint Admission and Power Control for Cognitive Radio Cellular Networks. I Wong, Lawrence & Wei, Gang (Red.), The 11th IEEE International Conference on Communication Systems 2008 (ICCS 2008). IEEE Press. ISSN 978-1-4244-2423-8. s. 1519–1523.
• Lysne, Olav; Reinemo, Svein Arne; Skeie, Tor & Solheim, Åshild Grønstad (2008). Interconnection networks: Architectural challenges for utility computing data centers. Computer. ISSN 0018-9162. 41, s. 62–69.
• Robles-Gòmez, A; Bermudèz, A; Casado, R; Solheim, Åshild Grønstad; Sødring, T. & Skeie, Tor (2008). A New Distributed Management Mechanism for ASI Based Networks. Computer Communications. ISSN 0140-3664. 32(2), s. 294–304. doi: 10.1016/j.comcom.2008.10.010.
• Lysne, Olav; Montanana, JM; Flich, J; Duato, J; Pinkston, TM & Skeie, Tor (2008). An efficient and deadlock-free network reconfiguration protocol. IEEE transactions on computers. ISSN 0018-9340. 57, s. 762–779. doi: 10.1109/TC.2008.31.
• Bai, Aleksander; Skeie, Tor & Engelstad, Paal Einar (2007). A Model-Based Admission Control for 802.11e EDCA using Delay Predictions. I Olivers, Richard L. & Dahlberg, Teresa A* (Red.), International Performance Computing and Communications Conference (IPCCC). IEEE (Institute of Electrical and Electronics Engineers). ISSN 1-4244-1138-6. s. 226–235.
• Reinemo, Sve Arne & Skeie, Tor (2007). Effective Shortest Path Routing for Gigabit Ethernet. I Andonovic, Ivan & Thompson, John (Red.), Proceedings IEEE International Conference on Communications, ICC 2007. IEEE Sarnoff Symposium. ISSN 1-4244-0353-7. s. 6419–6424.
• Reinemo, Sve Arne; Skeie, Tor; Mejìa, Andrès; Flich, Jose & Duato, Jose (2007). Boosting Ethernet Performance by Segment-Based Routing. I D'Ambra, Pasqua (Red.), Euromicro Conference on Parallel, Distributed and Network-based Processing. IEEE (Institute of Electrical and Electronics Engineers). ISSN 0-7695-2784-1. s. 55–62.
• Grønsund, Pål Rolfsen; Engelstad, Paal Einar; Johnsen, Torbjørn & Skeie, Tor (2007). The physical performance and path loss in a fixed WiMAX deployment. I Mohsen, Guizani & Chen, Hsiao-Hwa (Red.), International Wireless Communications and Mobile Computing Conference (IWCMC2007). Association for Computing Machinery (ACM). ISSN 978-1-59593-695-0. s. 439–444.
• Grønsund, Pål Rolfsen; Engelstad, P.E.; Ayoun, Moti & Skeie, Tor (2007). Real Life Field Trial over a Pre-mobile WiMAX System with 4th Order Diversity. Lecture Notes in Computer Science (LNCS). ISSN 0302-9743. 4712.
• Grønsund, P.; Engelstad, P.E.; Johnsen, T. & Skeie, Tor (2007). Real Life Field Trial over a pre-mobile WiMAX System with 4th Order Diversity. Lecture Notes in Computer Science (LNCS). ISSN 0302-9743.
• Bai, Aleksander; Skeie, Tor & Engelstad, Paal E. (2007). Rate Configuration used in Interoperation between DiffServ and 802.11e EDCA, Proceedings of 16th IST Mobile and Wireless Communications Summit, 2007. IEEE. ISSN 963-8111-66-6.
• Sem-Jacobsen, Frank Olaf; Skeie, Tor; Lysne, Olav & Duato, Jose (2006). Dynamic Fault Tolerance with Misrouting in Fat Trees. I Feng, Wu-chi (Red.), Proceedings of the International Conference on Parallel Processing (ICPP). IEEE (Institute of Electrical and Electronics Engineers). ISSN 0-7695-2636-5. s. 33–42.
• Gomez, M.; Nordbotten, Nils Agne; Flich, J.; Lopez, Pedro; Robles, Antonio & Duato, J [Vis alle 7 forfattere av denne artikkelen] (2006). A Routing Methodology for Achieving Fault-Tolerance in Direct Networks. IEEE transactions on computers. ISSN 0018-9340.
• Solheim, Åshild Grønstad; Lysne, Olav; Skeie, Tor; Sødring, T.; Theiss, Ingebjørg Thelin & Johnsen, I. (2006). Routing for the ASI Fabric Manager. IEEE Communications Magazine. ISSN 0163-6804.
• Bai, Aleksander; Selvig, Bjørn; Skeie, Tor & Engelstad, Paal E. (2006). A Class Based Dynamic Admitted Time Limit Admission Control Algorithm for 802.11e EDCA, Proceedings of the 6th International Workshop on Applications and Services in Wireless Networks (ASWN 2006). Fraunhofer IRB Verlag. ISSN 978-3-8167-7111-1.
• Sem-Jacobsen, Frank Olaf; Skeie, Tor & Lysne, Olav (2005). A Dynamic Fault-Torlerant Routing Algorithm for Fat-trees. I Arabnia, Hamid R. (Red.), International Conference on Parallel and Distributed Processing Techniques and Applications. CSREA Press. ISSN 1-932415-58-0.
• Sem-Jacobsen, Frank Olaf; Skeie, Tor; Lysne, Olav; Tørudbakken, O.; Rongved, E. & Johnsen, B. (2005). Siamese-Twin: A Dynamically Fault-Tolerant Fat Tree. I Werner, Bob (Red.), International Parallel and Distributed Processing Symposium (IPDPS). IEEE (Institute of Electrical and Electronics Engineers). ISSN 0-7695-2312-9.
• Skeie, Tor; Johannessen, Svein & Holmeide, Øyvind (2004). Switched Ethernet in Automation Networking. I Zurawski, Richard (Red.), The Handbook on Information Technology in Industrial Automation. CRC Press. ISSN 0-8493-1985-4. s. 49-1–49-15.
• Gomez, M.; Flich, J.; Lopez, Pedro; Robles, Antonio; Duato, J & Nordbotten, Nils Agne [Vis alle 7 forfattere av denne artikkelen] (2004). An Effective Fault-Tolerant Routing Methodology for Direct Networks. I Eigenmann, Rudolf (Red.), Proceedings of the 2004 International Conference on Parallel Processing. IEEE (Institute of Electrical and Electronics Engineers). ISSN 0-7695-2197-5.
• Sem-Jacobsen, Frank Olaf; Reinemo, Sven-Arne; Skeie, Tor & Lysne, Olav (2004). Achieving Flow Level QoS in Cut-through Networks through Admission Control and DiffServ. I Arabnia, Hamid R. (Red.), Proceedings of the International Conference on Parallel and Distributed Processing Techniques and Applications (PDPTA). CSREA Press. s. 1084–1090.
• Skeie, Tor; Lysne, Olav; Flich, J.; Lopez, Pedro; Robles, Antonio & Duato, J (2004). LASH-TOR: A Generic Transition-Oriented Routing Algorithm. I Tzeng, Nian-Feng (Red.), Proceedings of the IEEE International Conference on Parallel and Distributed Systems (ICPADS). IEEE (Institute of Electrical and Electronics Engineers). s. 595–604.
• Horn, Geir; Lysne, Olav & Skeie, Tor (2004). The existence of a network of fixed-sized switches that satisfies any communication needs. I Arabnia, Hamid R. (Red.), Proceedings of the International Conference on Parallel and Distributed Processing Techniques and Applications (PDPTA). CSREA Press. s. 1056–1062.
• Nordbotten,, Nils; Skeie, Tor & Aakvaag., Niels (2004). Methods for service discovery in Bluetooth scatternets. Computer Communications. ISSN 0140-3664. 27(11), s. 1087–1096.
• Gomez, Maria; Duato, Jose; Flich, Jose; Lopez, Pedro; Robles, Antonio & Nordbotten, Nils [Vis alle 7 forfattere av denne artikkelen] (2004). An effcient fault-tolerant routing methodology for meshes and tori. IEEE computer architecture letters. ISSN 1556-6056.
• Gomez, M.; Duato, J; Flich, J.; Lopez, Pedro; Robles, Antonio & Nordbotten, Nils Agne [Vis alle 7 forfattere av denne artikkelen] (2004). An Efficient Fault-Tolerant Routing Methodology for Meshes and Tori. IEEE computer architecture letters. ISSN 1556-6056.
• Gomez, M.; Duato, J; Flich, J.; Lopez, Pedro; Robles, Antonio & Nordbotten, Nils Agne [Vis alle 7 forfattere av denne artikkelen] (2004). A New Adaptive Fault-Tolerant Routing Methodology for Direct Networks. Lecture Notes in Computer Science (LNCS). ISSN 0302-9743.
• Nordbotten, Nils Agne; Gomez, M.; Flich, J.; Lopez, Pedro; Robles, Antonio & Skeie, Tor [Vis alle 7 forfattere av denne artikkelen] (2004). A Fully Adaptive Fault-Tolerant Routing Methodology Based on Intermediate Nodes. Lecture Notes in Computer Science (LNCS). ISSN 0302-9743.

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• Lu, Xiaoyi; Zhan, Jianfeng; Panda, Dhabaleswar K.; Bittencourt, Luiz F.; Chen, Yong & Gavrilovska, Ada [Vis alle 17 forfattere av denne artikkelen] (2019). Welcome to HPBDC 2019. 2019 IEEE International Parallel and Distributed Processing Symposium Workshops (IPDPSW). doi: 10.1109/IPDPSW.2019.00076.
• Skeie, Tor (2019). Energy Internet: Concepts and Key Technoloiges.
• Skeie, Tor (2018). Distributed Deep Learning.
• Zahid, Feroz; Gran, Ernst Gunnar & Skeie, Tor (2016). Realizing a Self-Adaptive Network Architecture for HPC Clouds.
• Pham, Hai Ngoc; Zhang, Yan; Engelstad, Paal Einar; Skeie, Tor & Eliassen, Frank (2010). Energy Minimization Approach for Optimal Cooperative Spectrum Sensing in Sensor-Aided Cognitive Radio Networks. Vis sammendrag

  In a sensor-aided cognitive radio network, collaborating battery-powered sensors are deployed to aid the network in cooperative spectrum sensing. These sensors consume energy for spectrum sensing and therefore deplete their life-time, thus we study the key issue in minimizing the sensing energy consumed by such group of collaborating sensors. The IEEE P802.22 standard specifies spectrum sensing accuracy by the detection and false alarm probabilities, hence we address the energy minimization problem under this detection accuracy constraint. Firstly, we derive the bounds for the number of sensors to simultaneously guarantee the thresholds for high detection probability and low false alarm probability. With these bounds, we then formulate the optimization problem to find the optimal sensing interval and the optimal number of sensor that minimize the energy consumption. Thirdly, the approximated analytical solutions are derived to solve the optimization accurately and efficiently in polynomial time. Finally, numerical results show that the minimized energy is significantly lower than the energy consumed by a group of randomly selected sensors. The mean absolute error of the approximated optimal sensing interval compared with the exact value is less than 4% and 8% under good and bad SNR conditions, respectively. The approximated optimal number of sensors is shown to be very close to the exact number.

• Solheim, Åshild Grønstad; Lysne, Olav; Sødring, T.; Skeie, Tor & Libak, J. A. (2008). Routing-Contained Virtualization based on Up*/Down* Forwarding. I Aluru, Srinivas; Parashar, Manish; Badrinath, Ramamurthy & Prasanna, Viktor K. (Red.), High Performance Computing - HiPC 2007: 14th International Conference. Springer. ISSN 978-3540772194. s. 500–513.
• Pham, Hai Ngoc; Xiang, Jie; Yan, Zhang & Skeie, Tor (2008). QoS-Aware Channel Selection in Cognitive Radio Networks: A Game-Theoretic Approach. Vis sammendrag

  In a cognitive radio wireless network, each node can sense and opportunistically access the under-utilized spectrums in the primary system. Since the unoccupied spectrum is location-dependent and time-dependent, the available spectrums in each node are different. With this spectrum heterogeneity and different Quality-of-Service (QoS) requirement, different nodes may have different preferences in using a particular channel to communicate with its neighboring nodes. In this paper, we formulate this channel selection problem using a cooperative game theoretical approach such that the QoS requirement of each node is guaranteed and the network capacity is maximized. To further improve the performance, a learning negotiation mechanism is introduced. The key motivation is to derive new mixed strategies of the nodes with the reference to the historical profiles of all selected strategies in the past. Simulation results are presented to show the fast convergence of the game, the high efficiency of the learning mechanism, and the effect of mobility.

• Grønsund, P.; Engelstad, P.E.; Johnsen, T. & Skeie, Tor (2007). The Physical Performance and Path Loss in a Fixed WiMAX Deployment.
• Grønsund, P.; Engelstad, P.E.; Johnsen, T. & Skeie, Tor (2007). Real Life Field Trial over a pre-mobile WiMAX System with 4th Order Diversity.
• Solheim, Åshild Grønstad; Lysne, Olav; Sødring, T.; Skeie, Tor & Libak, J. A. (2007). Routing-Contained Virtualization based on Up*/Down* Forwarding.
• Sem-Jacobsen, Frank Olaf; Skeie, Tor; Lysne, Olav & Duato, Jose (2006). Dynamic Fault Tolerance with Misrouting in Fat Trees.
• Bai, Aleksander; Skeie, Tor & Engelstad, Paal E. (2006). Rate Configuration used in Interoperation between DiffServ and 802.11e EDCA.
• Bai, Aleksander; Selvig, Bjørn; Skeie, Tor & Engelstad, Paal E. (2006). A Class Based Dynamic Admitted Time Limit Admission Control Algorithm for 802.11e EDCA.
• Sem-Jacobsen, Frank Olaf; Skeie, Tor; Lysne, Olav; Tørudbakken, O.; Rongved, E. & Johnsen, B. (2005). Siamese-Twin: A Dynamically Fault-Tolerant Fat Tree.
• Sem-Jacobsen, Frank Olaf; Skeie, Tor & Lysne, Olav (2005). A Dynamic Fault-Torlerant Routing Algorithm for Fat-trees.
• Selvig, Bjørn; Bai, Aleksander; Skeie, Tor & Engelstad, Paal E. (2005). Differentiated Services in 802.11e WLANs.
• Lysne, Olav; Skeie, Tor; Theiss, Ingebjørg Thelin; Rognved, B. D. & Tørudbakken, O. (2004). The Interconnection Network: Architectural Challenges for Datacenters in the Computational GRID.
• Horn, Geir; Lysne, Olav & Skeie, Tor (2004). The existence of a network of fixed-sized switches that satisfies any communication needs.
• Gomez, Maria; Flich, Jose; Lopez, Pedro; Robles, Antonio; Duato, Jose & Nordbotten, Nils [Vis alle 7 forfattere av denne artikkelen] (2004). An effective fault-tolerant routing methodology for direct networks.
• Taherkordi, Amirhosein; Eliassen, Frank & Skeie, Tor (2011). Programming Wireless Sensor Networks: From Static to Adaptive Models. Unipub forlag.

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