@inproceedings {Simula.simula.856,
	title = {PreeN: Improving Steady-State Performance of ISP-Friendly P2P Applications},
	journal = {13th International conference on Distributed Computing and Networking, ICDCN 2012},
	volume = {7129},
	year = {2012},
	month = {January},
	publisher = {Springer},
	type = {Conference},
	abstract = {Much effort has been put into making P2P applications ISP-friendly, i.e. finding a solution that reduces inter-ISP traffic while maintaining the high file-sharing efficiency of existing P2P applications. Related works have analyzed different ISP-friendly P2P solutions by simulations. However, most of these simulation models have two common assumptions; 1) the peer arrival process follows a flash-crowd scenario, 2) the distribution of peers follows a uniform distribution. Most of the time, both these assumptions are not true for a P2P network. In this paper we show that the peer arrival process and the distribution of peers have a significant effect on the simulation results. We also show that solutions perform differently, e.g. in terms of the amount of inter-ISP traffic and download time, in a flash crowd scenario than in a steady state, limiting the applicability of the results and conclusions reported in previous works. Based on this new insight, we propose a Preemptive Neighbor Selection (PreeN) that makes an ISP-friendly P2P application efficient in steady state scenarios.},
	author = {Shams, Saif and Kvalbein, Amund and Paal Einar {Engelstad}},
	editor = {Bononi, L. and Datta, A. and Devismes, S. and Misra, A.}
}
@inproceedings {Simula.simula.858,
	title = {On Randomness in ISP-Friendly P2P Applications},
	journal = {The 26th IEEE International Conference on Advanced Information Networking and Applications, AINA-2012},
	year = {2012},
	month = {March},
	publisher = {IEEE},
	type = {Conference},
	abstract = {P2P networking is a popular technology for sharing large files efficiently without using powerful servers. The goal for a P2P file sharing application is to minimize the download time experienced by the peers. However, the efficiency of a P2P network comes at the expense of excessive network utilization. ISPs want to control the network utilization of P2P applications, and in particular it is desirable to minimize the inter-ISP traffic. The often contradicting interests of applications and network owners have led to the search for an ISP-friendly P2P application that reduces inter-ISP traffic while maintaining the high file-sharing efficiency. Existing solutions propose to localize most of the P2P traffic within the ISP, while randomly selecting a few external peers to ensure the global spread of content. However, these proposals disregard the inherent randomness that will naturally exist in P2P systems. In this paper, we analyze the different sources of inherent randomness in ISP-friendly P2P systems, and show that they can have a significant impact on performance, and therefore must be taken into account when designing new solutions.},
	author = {Shams, Saif and Kvalbein, Amund and Paal Einar {Engelstad}}
}
@inproceedings {Simula.simula.178,
	title = {Improving the Performance of Quality-Adaptive Video Streaming Over Multiple Heterogeneous Access Networks},
	journal = {Proceedings of the second annual ACM conference on Multimedia systems (MMSYS)},
	year = {2011},
	month = {February},
	pages = {57-68},
	publisher = {ACM},
	type = {Conference},
	abstract = {Devices capable of connecting to multiple, overlapping networks simultaneously are becoming increasingly common. For example, most laptops are equipped with LAN- and WLAN-interfaces, and smart phones can typically connect to both WLANs and 3G mobile networks. At the same time, streaming high-quality video is becoming increasingly popular. However, due to bandwidth limitations or the unreliable and unpredictable nature of some types of networks, streaming video can be subject to frequent periods of rebuffering and characterised by a low picture quality. In this paper, we present a client-side request scheduler that distributes requests for the video over multiple heterogeneous interfaces simultaneously. Each video is divided into independent segments with constant duration, enabling segments to be requested over separate links, utilizing all the available bandwidth. To increase performance even further, the segments are divided into smaller subsegments, and the sizes are dynamically calculated on the fly, based on the throughput of the different links. This is an improvement over our earlier subsegment approach, which divided segments into fixed size subsegments. Both subsegment approaches were evaluated with on-demand streaming and quasi-live streaming. The new subsegment approach reduces the number of playback interruptions and improves video quality significantly for all cases where the earlier approach struggled. Otherwise, they show similar performance.},
	isbn = {978-1-4503-0518-1},
	author = {Evensen, Kristian and Kaspar, Dominik and Griwodz, Carsten and Halvorsen, P{\r a}l and Audun Fosselie {Hansen} and Paal Einar {Engelstad}},
	editor = {Ketan Mayer-Pate {Begen}}
}
@article {Simula.simula.860,
	title = {Using Bandwidth Aggregation to Improve the Performance of Quality-Adaptive Streaming},
	journal = {Signal Processing: Image Communication},
	volume = {27},
	number = {4},
	year = {2011},
	pages = {312-328},
	publisher = {Elsevier},
	abstract = {Devices capable of connecting to multiple, overlapping networks simultaneously is becoming increasingly common. For example, most laptops are equipped with LAN- and WLAN-interface, and smart phones can typically connect to both WLANs and 3G mobile networks. At the same time, streaming high-quality video is becoming increasingly popular. However, due to bandwidth limitations or the unreliable and unpredictable nature of some types of networks, streaming video can be subject to frequent periods of rebuffering and characterized by a low picture quality. In this paper, we present a multilink extension to the data retrieval part of the DAVVI adaptive, segmented video streaming system. DAVVI implements the same core functionality as the MPEG DASH standard. It uses HTTP to retrieve data, segments video, provides clients with a description of the content, and allows clients to switch quality during playback. Any DAVVI-data retrieval extensions can also be implemented in a DASH-solution. The multilink-enabled DAVVI client divides video segments into smaller subsegments, which are requested over multiple interfaces simultaneously. The size of each subsegment is dynamic and calculated on the fly, based on the throughput of the different links. This is an improvement over our earlier subsegment approach, which divided segments into fixed size subsegments. The quality of the video is adapted based on the measured, aggregated throughput. Both the static and the dynamic subsegment approaches were evaluated with on-demand streaming and quasi-live streaming. The new subsegment approach reduces the number of playback interruptions and improves video quality significantly for all cases where the earlier approach struggled. Otherwise, they show similar performance.},
	doi = {doi:10.1016/j.image.2011.10.007},
	author = {Evensen, Kristian and Kaspar, Dominik and Griwodz, Carsten and Halvorsen, P{\r a}l and Audun Fosselie {Hansen} and Paal Einar {Engelstad}}
}
@inproceedings {Simula.ND.387,
	title = {A Dynamic Spectrum Access Scheme for Unlicensed Systems Coexisting With Primary OFDMA Systems},
	journal = {The 7th Annual IEEE Consumer Communications and Networking Conference (CCNC)},
	year = {2010},
	publisher = {IEEE},
	type = {Conference},
	abstract = {In this paper, we consider Mobile WiMAX and LTE as the future technologies for primary OFDMA systems and study Dynamic Spectrum Access (DSA) for unlicensed systems coexisting with primary OFDMA systems. We propose an effective DSA scheme that allows an unlicensed system to statistically and opportunistically access the whole spectrum bandwidth during the last consecutive symbols of each primary OFDMA subframe. There is a tradeoff in gaining high normalized throughput by enlarging the access duration in each subframe and keeping low interference caused to the primary system by shorten the access period. Then, we model that tradeoff by deriving the optimization problem that maximizes the normalized throughput of the unlicensed system while guaranteeing the harmful interference constraints set by the primary system. We develop and conduct our simulations in our simulator modified from the powerful WiMAX simulator developed by the WiMAX Forum in Ns-2.},
	isbn = {978-1-4244-5176-0},
	author = {Hai Ngoc {Pham} and P{\r a}l Rolfsen {Gr{\o}nsund} and Paal Einar {Engelstad} and Gr{\o}dalen, Ole},
	editor = {Ott, J{\"o}rg and Balandin, Sergey and Matuszewski, Marcin}
}
@inproceedings {Simula.ND.403,
	title = {Energy Minimization Approach for Optimal Cooperative Spectrum Sensing in Sensor-Aided Cognitive Radio Networks},
	journal = {2010 The 5th Annual ICST Wireless Internet Conference (WICON 2010)},
	year = {2010},
	publisher = {ICST/Create-Net},
	type = {Conference},
	abstract = {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.},
	isbn = {978-963-9799-86-8},
	author = {Hai Ngoc {Pham} and Zhang, Yan and Paal Einar {Engelstad} and Skeie, Tor and Eliassen, Frank},
	editor = {Mahmoud Daneshmand {Chen}}
}
@inproceedings {Simula.ND.379,
	title = {Enhancing Video-on-Demand Playout Over Multiple Heterogeneous Access Networks},
	journal = {Consumer Communications and Networking Conference (CCNC)},
	year = {2010},
	publisher = {IEEE},
	type = {Conference},
	abstract = {Multimedia streaming is increasing in popularity and has become one of the dominating services on the Internet today. Even though user devices are often equipped with multiple network interfaces and in reach of several access networks at the same time, media streams are normally communicated over only one of the available Internet connections. In this paper, we explore the challenges and potential benefits of using multiple access networks simultaneously. Exploiting HTTP{\textquoteright}s capability of handling requests for specific byte ranges of a file, we present the implementation of a lightweight, application-layer, on-demand streaming service that requires no changes to existing servers and infrastructure. Based on real-world experiments with a multihomed host, we investigate the potential performance gains of video-on-demand playout. We achieve a bandwidth aggregation efficiency of 90\% when downloading over 3 heterogeneous access networks in parallel. In addition, we analyze the effect of file segmentation on the buffer requirements and the startup latency.},
	isbn = {978-1-4244-5176-0},
	author = {Kaspar, Dominik and Evensen, Kristian and Paal Einar {Engelstad} and Audun Fosselie {Hansen} and Halvorsen, P{\r a}l and Griwodz, Carsten},
	editor = {IEEE, }
}
@inproceedings {Simula.telco.16,
	title = {Gateway Selection Scheme for Throughput Optimization in Multi-Radio Multi-Channel Wireless Mesh Networks Under Physical Interference Model},
	journal = {Proceedings of the 5th International Conference on Communications and Networking in China, (Invited Paper), ChinaCom 2010},
	year = {2010},
	publisher = {IEEE},
	type = {Conference},
	isbn = {973-963-9799-97-4},
	author = {Xin, Qin and Yao, Xin and Paal Einar {Engelstad}},
	editor = {Hsiao-Hwa Chen et {al.}}
}
@inproceedings {Simula.telco.18,
	title = {Latency-Efficient Communication in Wireless Mesh Networks Under Consideration of Large Interference Range},
	journal = {Proceedings of 8th International Conference of Numerical Analysis and Applied Mathematics},
	year = {2010},
	publisher = {American Institute of Physics},
	type = {Conference},
	isbn = {978-0-7354-0834-0},
	author = {Xin, Qin and Yao, Xin and Paal Einar {Engelstad}},
	editor = {Theodore E. {Simos} and Psihoyios, George and Tsitouras, Ch.}
}
@inproceedings {Simula.nd.441,
	title = {A Model for the Loss of Hello-Messages in a Wireless Mesh Network},
	journal = {Proceedings of ICC 2010},
	year = {2010},
	publisher = {IEEE},
	type = {Conference},
	author = {Egeland, Geir and Paal Einar {Engelstad}}
}
@inproceedings {Simula.nd.439,
	title = {Using HTTP Pipelining to Improve Progressive Download Over Multiple Heterogeneous Interfaces},
	journal = {International Conference on Communications (ICC)},
	year = {2010},
	pages = {1-5},
	publisher = {IEEE},
	type = {Conference},
	abstract = {Today, mobile devices like laptops and cell phones often come equipped with multiple network interfaces, enabling clients to simultaneously connect to independent access networks. Even though applications, such as multimedia streaming and video-on-demand delivery systems, could potentially benefit greatly from the aggregated bandwidth, implementation and standardization challenges have so far hindered the deployment of multilink solutions. Previously, we have explored the benefits of collaboratively using multiple Internet connections to progressively download and play back large multimedia files. In this paper, we present an improved version of our approach that utilizes HTTP{\textquoteright}s capability of request pipelining in combination with range retrieval requests. While, in our earlier work, the optimal choice of file segmentation size presented a tradeoff between throughput and startup latency, the enhanced solution is able to overcome this tradeoff. The use of very small segments no longer impairs the efficiency of throughput aggregation, which additionally makes our solution robust against link variances and agnostic to network heterogeneity. Read},
	isbn = {978-1-4244-6404-3},
	author = {Kaspar, Dominik and Evensen, Kristian and Paal Einar {Engelstad} and Audun Fosselie {Hansen}},
	editor = {Wilhelm Leuschner {Takawira}}
}
@inproceedings {Simula.ND.401,
	title = {Analysis of Peer Selection Algorithms in Cross-Layer P2P Architectures},
	journal = {International Workshop on Advances in Peer-to-Peer Technology, IWAP2PT09},
	year = {2009},
	month = {December},
	publisher = {IEEE COMSOC},
	type = {Workshop},
	abstract = {The large amount of peer-to-peer (P2P) traffic in today{\textquoteright}s Internet represents a great challenge for most Internet Service providers (ISPs). P2P traffic does not conform to traditional ISP traffic policies, and it makes it harder to perform traffic engineering in the network. It is especially the peer-selection mechanism of the P2P application that influences the traffic patterns and creates an imbalance for the ISP business. Some ISPs benefit from the P2P traffic, while others suffer. There are research efforts proposing cross-layer solutions where the P2P application uses the underlying routing information for the peer selection. These works put a lot of focus on improving the application performance, but take to a little extent into account how the ISPs are affected. In this paper we propose a framework to measure the effects of the peer-selection mechanism, not only on the P2P application performance, but also on the economy of different types of ISPs. We categorize all ISPs into three groups; core, transit and stub, depending on their position in the global Internet hierarchy. Using our proposed framework, we analyze the performance of different peer-selection algorithms.},
	author = {Shams, Saif and Paal Einar {Engelstad} and Kvalbein, Amund}
}
@inproceedings {Simula.ND.307,
	title = {An Analysis of the Heterogeneity and IP Packet Reordering Over Multiple Wireless Networks},
	journal = {IEEE Symposium on Computers and Communications (ISCC)},
	number = {CFP09SCC},
	year = {2009},
	pages = {637-642},
	publisher = {IEEE},
	type = {Conference},
	abstract = {With the increasing deployment of wireless technologies, such as WLAN, HSPA, and WiMAX, it is often the case that simultaneous coverage of several access networks is available to a single user device. In addition, devices are also often equipped with multiple network interfaces. Thus, if we can exploit all available network interfaces at the same time, we can obtain advantages like the aggregation of bandwidth and increased fault tolerance. However, the heterogeneity and dynamics of the links also introduce challenges. Due to different link delays, sending packets of the same flow over multiple heterogeneous paths causes the reordering of packets. In this paper, we quantify how network heterogeneity and the use of multiple links affect IP packet reordering. We show with practical measurements, according to commonly used metrics, that packet reordering over multiple links exceeds the reordering caused by common connections in high-speed, wide-area networks. We also demonstrate the heterogeneity and reordering exceeds the assumptions presented in related work. By using sufficiently large buffers, packet reordering can be avoided. However, for devices with high resource constraints, the workload of using large buffers is expensive. Sender-side solutions of dividing and scheduling a packet sequence to available links towards the client can reduce the buffer requirements. Initial experiments with a static scheduler that has knowledge of average link delay and throughput estimates show that packet reordering can be reduced by only 38\% due to the dynamic heterogeneity of the two links.},
	isbn = {978-1-4244-4671-1},
	author = {Kaspar, Dominik and Evensen, Kristian and Audun Fosselie {Hansen} and Paal Einar {Engelstad} and Halvorsen, P{\r a}l and Griwodz, Carsten}
}
@article {Simula.nd.419,
	title = {The Availability and Reliability of Wireless Multi-Hop Networks With Stochastic Link Failures},
	journal = {IEEE Journal on Selected Areas in Communications},
	volume = {27},
	number = {7},
	year = {2009},
	month = {September},
	publisher = {IEEE},
	doi = {10.1109/JSAC.2009.090910},
	author = {Egeland, Geir and Paal Einar {Engelstad}}
}
@inproceedings {Simula.nd.421,
	title = {The Economy of Redundancy in Wireless Multi-Hop Networks},
	journal = {IEEE Wireless Communications and Networking Conference (WCNC 2009)},
	year = {2009},
	month = {April},
	publisher = {ieee},
	type = {Conference},
	isbn = {978-1-4244-2948-6},
	author = {Egeland, Geir and Paal Einar {Engelstad}},
	editor = {Hanzo, Lajos}
}
@inproceedings {Simula.nd.427,
	title = {Energy Penalties for Non-Shortest Paths in Wireless Sensor Networks With Link Failures},
	journal = {The 5th International Wireless Communications and Mobile Computing Conference (IWCMC{\textquoteright}09)},
	year = {2009},
	month = {June},
	publisher = {ACM},
	type = {Conference},
	isbn = {978-1-60558-569-7},
	author = {Egeland, Geir and Paal Einar {Engelstad}}
}
@inproceedings {Simula.ND.369,
	title = {A Network-Layer Proxy for Bandwidth Aggregation and Reduction of IP Packet Reordering},
	journal = {The 34rd Annual IEEE Conference on Local Computer Networks (LCN)},
	year = {2009},
	month = {July},
	pages = {585-592},
	publisher = {IEEE},
	type = {Conference},
	abstract = {With today\&$\#$39;s widespread deployment of wireless technologies, it is often the case that a single communication device can select from a variety of access networks. At the same time, there is an ongoing trend towards integration of multiple network interfaces into end-hosts, such as cell phones with HSDPA, Bluetooth and WLAN. By using multiple Internet connections concurrently, network applications can benefit from aggregated bandwidth and increased fault tolerance. However, the heterogeneity of wireless environments introduce challenges with respect to implementation, deployment, and protocol compatibility. Variable link characteristics cause reordering when sending IP packets of the same flow over multiple paths. This paper introduces a multilink proxy that is able to transparently stripe traffic destined for multihomed clients. Operating on the network layer, the proxy uses path monitoring statistics to adapt to changes in throughput and latency. Experimental results obtained from a proof-of-concept implementation verify that our approach is able to fully aggregate the throughput of heterogeneous downlink streams, even if the path characteristics change over time. In addition, our novel method of equalizing delays by buffering packets on the proxy significantly reduces IP packet reordering and the buffer requirements of clients.},
	isbn = {978-1-4244-4488-5},
	doi = {10.1109/LCN.2009.5355198},
	author = {Evensen, Kristian and Kaspar, Dominik and Paal Einar {Engelstad} and Audun Fosselie {Hansen} and Griwodz, Carsten and Halvorsen, P{\r a}l}
}
@inproceedings {Simula.ND.377,
	title = {Optimal Cooperative Spectrum Sensing in Cognitive Sensor Networks},
	journal = {The 5th International Wireless Communications and Mobile Computing Conference (IWCMC {\textquoteright}09)},
	year = {2009},
	pages = {1073-1079},
	publisher = {ACM New York, NY, USA},
	type = {Conference},
	abstract = {This paper addresses the problem of optimal cooperative spectrum sensing in a cognitive-enabled sensor network where cognitive sensors can cooperate in the sensing of the spectrum. Such sensor networks are assumed to be power resource constrained. With a given threshold for the accuracy of the spectrum detection, we find the optimal number of cognitive sensors participating in the cooperative spectrum sensing and the optimal sensing interval that minimize the total energy consumption of the cooperative sensing. First, the mathematical lower bound and upper bound for the number of cooperative cognitive sensors are found. Then the optimization problem to minimize the total energy consumed by a group of sensors is presented. Finally, an efficient approximate solution to the optimization problem is proposed. Numerical calculations validate the accuracy and the performance of the proposed scheme. The impact of the noise uncertainty, the choice of the energy detection threshold, and the spectrum bandwidth on the detection accuracy and the minimum total energy consumption is also studied.},
	isbn = {978-1-60558-569-7},
	author = {Hai Ngoc {Pham} and Zhang, Yan and Paal Einar {Engelstad} and Skeie, Tor and Eliassen, Frank}
}
@inproceedings {Simula.nd.429,
	title = {Performance Analysis of Gateway Load Balancing in Ad Hoc Networks With Random Topologies},
	journal = {The 7th ACM International Symposium on Mobility Management and Wireless Access (Mobiwac09)},
	year = {2009},
	month = {October},
	publisher = {ACM},
	type = {1},
	isbn = {978-1-59593-809-1},
	author = {Pham, Vinh and Larsen, Erlend and Paal Einar {Engelstad} and Kure, {\O}ivind},
	editor = {Mobiwac, }
}
@inproceedings {Simula.nd.431,
	title = {Preemption Mechanisms for Push-to-Talk in Ad Hoc Networks},
	journal = {The 34th Annual IEEE Conference on Local Computer Networks (LCN)},
	year = {2009},
	publisher = {IEEE},
	type = {Conference},
	isbn = {978-1-4244-4487-8},
	author = {Larsen, Erlend and Pham, Vinh and Paal Einar {Engelstad} and Kure, {\O}ivind}
}
@article {Simula.nd.423,
	title = {Routing of Internal MANET Traffic Over External Networks},
	journal = {Mobile Information Systems},
	volume = {5},
	number = {3},
	year = {2009},
	month = {August},
	pages = {291-311},
	publisher = {ACM},
	abstract = {Many have proposed to connect Mobile Ad Hoc Networks (MANETs) to a wired backbone Internet access network. This paper demonstrates that a wired backbone network can be utilized for more than just providing access to the global Internet. Traffic between mobile nodes in the ad hoc network may also be routed via this backbone network to achieve higher throughput, and to reduce the load in the ad hoc network. This is referred to as transit routing. This paper proposes a cost metric algorithm that facilitates transit routing for some of the traffic flows between nodes in the MANET. The algorithm aims at carrying out transit routing for a flow only when it leads to improvements of the performance. The proposal is implemented and tested in the ns-2 network simulator, and the simulation results are promising.},
	author = {Pham, Vinh and Larsen, Erlend and Kure, {\O}ivind and Paal Einar {Engelstad}}
}
@inproceedings {Simula.nd.425,
	title = {Routing With Transmission Buffer Zones in MANETs},
	journal = {10th IEEE International Symposium on a World of Wireless, Mobile and Multimedia Networks (WoWMoM{\textquoteright}09)},
	year = {2009},
	month = {June},
	publisher = {IEEE},
	type = {Conference},
	isbn = {978-1-4244-4440-3},
	author = {Larsen, Erlend and Landmark, Lars and Pham, Vinh and Kure, {\O}ivind and Paal Einar {Engelstad}},
	editor = {Giordano, Silvia and Siris, Vasilios}
}
@inproceedings {Simula.ND.375,
	title = {Towards Dynamic Spectrum Access in Primary OFDMA Systems},
	journal = {The 20th Personal, Indoor and Mobile Radio Communications Symposium 2009 (PIMRC{\textquoteright}09)},
	year = {2009},
	pages = {848-852},
	type = {Conference},
	abstract = {OFDMA will be the major transmission technology in the future mobile wireless broadband systems, and is already used in Mobile WiMAX and LTE. In this paper, we use simulations to characterize the spectrum usage of such primary systems. This knowledge is useful for cognitive radio and other technologies for dynamic spectrum access that aim at improving the overall spectrum usage. We calculate the available capacity and analyze the distribution of the spectrum occupancy over time for various network scenarios and traffic models. Based on our analyses, we finally propose directions for improving the dynamic access of spectrum allocated to primary OFDMA systems.},
	author = {P{\r a}l Rolfsen {Gr{\o}nsund} and Hai Ngoc {Pham} and Paal Einar {Engelstad}}
}
@inproceedings {Simula.ND.86,
	title = {Could Proactive Link-State Routed Wireless Networks Benefit From Local Fast Reroute?},
	journal = {6th annual Communication Networks and Services Research Conference, 2008. CNSR 2008},
	year = {2008},
	month = {May},
	pages = {453-462},
	publisher = {IEEE},
	type = {Conference},
	abstract = {The communication performance in wireless net- works is often heavily influenced by failures caused by node mobility and radio disturbance. Proactive link- state routing protocols like OLSR and OSPFv3 with wireless extensions (WOSPF) are currently relying on slow re-convergence to restore successful packet for- warding. This may not be appropriate for particular applications, and it may cause instability during tran- sient failures. Support for fast and local reroute should therefore be added as a feature to proactive link-state based routing protocols. In this paper, we discuss the challenges and requirements that are associated with such solutions. In addition, we evaluate and discuss to what extent recent developments for fixed IP routing can serve as solutions. To our best knowledge, no pub- lished work presents a similar study on fast recovery in proactive link-state routed wireless networks.},
	isbn = {978-0-7695-3135-9},
	doi = {10.1109/CNSR.2008.26},
	author = {Audun Fosselie {Hansen} and Egeland, Geir and Paal Einar {Engelstad}},
	editor = {Patrick Kellenberg {IEEE}}
}
@inproceedings {Simula.ND.6,
	title = {A Model-Based Admission Control for 802.11e EDCA Using Delay Predictions},
	journal = {The 26th IEEE International Performance Computing and Communications Conference (IPCCC)},
	year = {2007},
	month = {April},
	pages = {226-235},
	publisher = {IEEE Computer Society Press},
	type = {Conference},
	abstract = {This paper presents a unique approach for a model-based admission control algorithm for the IEEE 802.11e Enhanced Distributed Channel Access (EDCA) standard. The analytical model used as the foundation for the algorithm covers both non-saturation and saturation conditions. This allows us to keep the system out of saturation by monitoring several variables. Since the medium access delay represents the service time of the system, it is used as the threshold condition to ensure that the queuing delay is within reasonable bounds. The paper describes the admission control algorithm and several simulation results are presented and discussed.},
	isbn = {1-4244-1138-6},
	author = {Bai, Aleksander and Skeie, Tor and Paal Einar {Engelstad}}
}
@inproceedings {Simula.ND.30,
	title = {The Physical Performance and Path Loss in a Fixed WiMAX Deployment},
	journal = {International Wireless Communications and Mobile Computing Conference},
	year = {2007},
	month = {August},
	pages = {439-444},
	publisher = {ACM Press},
	type = {Conference},
	abstract = {Fixed WiMAX is being deployed worldwide, and the networks are increasing in size. Measurements have been performed, but the amount of measurements are few and do therefore not demonstrate performance in a real life deployment. We have performed extensive analyses of the physical performance in a fixed WiMAX deployment which has been operative for a year and where the amount of subscribers constantly increases. The analyses presented in this paper focus on received signal strength and signal to noise ratio. Based on the measured parameters, we present a Path Loss model for fixed WiMAX which will hopefully be of great reference value due to the great amount of measurements presented. Finally, our Path Loss model is compared to other well known Path Loss models and is found to approach the free space loss model.},
	isbn = {978-1-59593-695-0},
	author = {Gr{\o}nsund, P{\r a}l and Paal Einar {Engelstad} and Johnsen, Torbj{\o}rn and Skeie, Tor},
	editor = {Guizani, Mohsen and Chen, Hsiao-Hwa}
}
@inproceedings {Simula.ND.40,
	title = {Real Life Field Trial Over a Pre-Mobile WiMAX System With 4th Order Diversity},
	journal = {The 7th International Conference on Next Generation Teletraffic and Wired/Wireless Advanced Networking (NEW2AN)},
	year = {2007},
	month = {September},
	pages = {121-132},
	publisher = {LNCS Springer},
	type = {Conference},
	abstract = {Mobile WiMAX is a promising wireless technology approaching market deployment. Much discussion concentrate on whether mobile WiMAX will reach a tipping point and become 4G or not. As a pre-mobile WiMAX system is being delivered, we decided to set up a real life field trial and perform the most important measurements over the system setup. The system was delivered with 4th order diversity. In this paper we analyze physical system performance based on field trial measurements, especially at locations with non line of sight conditions in urban areas. We investigate the gain with 2nd and 4th order base station diversity and derive analytical expressions. The system path loss is plotted and found to approach the Cost-231 Hata model for urban areas. Throughput is also measured and analyzed. Sub-channelization in the uplink points out to be an important feature for enhanced coverage.},
	isbn = {978-3-54074-832-8},
	author = {Gr{\o}nsund, P{\r a}l and Paal Einar {Engelstad} and Ayoun, Moti and Skeie, Tor},
	editor = {Koucheryavy, Yevgeni}
}
@inproceedings {Bai.2006.1,
	title = {A Class Based Dynamic Admitted Time Limit Admission Control Algorithm for 802.11e EDCA},
	journal = {Proceedings of the 6th International Workshop on Applications and Services in Wireless Networks (ASWN)},
	year = {2006},
	month = {May},
	pages = {243-249},
	publisher = {Fraunhofer FOKUS},
	type = {Workshop},
	abstract = {This paper presents a class based dynamic admission control algorithm for the IEEE 802.11e Enhanced Distributed Channel Acccess (EDCA) standard. The strength of our admission control is the dynamic and flexibility of the algorithm, which adapts to the situation and thus achieves higher throughput than other admission controls for 802.11 EDCA. The achievements of our admission control are presented and evaluated. Class and flow utilization is discussed before a special case of our admission control algorithm aimed at flow utilization is given.},
	isbn = {ISBN 10:3-8167-7111-4, ISBN 13:978-3-8167-7111-1},
	author = {Bai, Aleksander and Selvig, Bj{\o}rn and Skeie, Tor and Paal Einar {Engelstad}},
	editor = {Arbanowski, Stefan}
}
@inproceedings {Hansen.2006.2,
	title = {Profiles and Multi-Topology Routing in Highly Heterogeneous Ad Hoc Networks},
	journal = {INFOCOM 2006, Poster and Demo session, Barcelona, Spain April 23-29},
	year = {2006},
	month = {April},
	publisher = {IEEE},
	type = {1},
	abstract = {This paper points out multi-parameter heterogeneity as one of the main research challenges for future ad hoc network scenarios. Current research is often focusing on dealing with heterogeneity in terms of only one property, such as battery life or link capacity. Instead, we argue for a more holistic approach that can deal with heterogeneity in terms of a number of different parameters simultaneously. Profiled routing and multitopology routing are proposed as possible solutions.},
	author = {Audun Fosselie {Hansen} and Cicic, Tarik and Paal Einar {Engelstad}}
}
@inproceedings {Bai.2006.2,
	title = {On the Use of Rate Configuration in the Interoperation Between DiffServ and 802.11e EDCA},
	journal = {Proceedings of the 15th IST Mobile \& Wireless Communications},
	year = {2006},
	month = {June},
	publisher = {National Technical University of Athens},
	type = {Conference},
	address = {Heroon Polytechniou, 15773 Athens, Greece},
	abstract = {This paper investigates rate configuration of the Expedited Forwarding (EF) class of Differentiated Services (DiffServ) when used with 802.11e EDCA. The rate configuration problem is presented, and several approaches are tested and evaluated in order to solve the problem. Results reveal that the contention window makes rate configuration very hard for the highest priority class (AC\_VO) in 802.11e EDCA. Our evaluations show that 802.11e EDCA is not able to conform to DiffServ{\textquoteright}s EF PHB specifications.},
	isbn = {NA},
	author = {Bai, Aleksander and Skeie, Tor and Paal Einar {Engelstad}},
	editor = {Emmanuel N. {Protonotarios}}
}
