Vol. 63, n°7-8, September-October 2008
Content available on SpringerLink http://www.springerlink.com/content/120920/
Home networking: performance and architecture challenges
Khaldoun Al Agha (Univ. Paris XI, France), Walter Grote (Univ. FSM - Chile), Yukata Takahashi (Kyoto Univ., Japan)
K. Al Agha, W. Grote, Y. Takahashi
Ultra wideband over fibre transparent architecture for high-bit-rate home networks
Anna Pizzinat, Franck Payoux, Benoît Charbonnier, Sylvain Meyer
France Telecom Research and Development, 2, Av. P. Marzin, 22307 Lannion, France
Abstract: Bandwidth hungry services are developing rapidly in home networking and needs for gigabit home networks will appear shortly, following the introduction of gigabit optical access networks. In addition, ubiquitous wireless connectivity is required by users to connect multiple multimedia devices inside the home. Some wireless standards, such as ultra wideband (UWB), are able to provide Gbps data rate but with a limited coverage. To extend the coverage of this system to the scale of the house, some possible architectures are presented. Among them, we focus on a multipoint-to-multipoint (MP2MP) radio-over-fibre (RoF) architecture based on a N× N optical splitter that is very promising. The UWB MAC layer is able to control the system and no optical MAC layer is required, so that the optical path becomes a "transparent tunnel". Simulations and experimental investigations demonstrate the technical feasibility of this innovative MP2MP RoF architecture.
Keywords: Radio over fiber . Home networks . Ultra wideband
IEEE 802.11 goodput analysis for mixed real-time and data traffic for home networks
Walter Grote, Alex Grote, Isabel Delgado
Electronic Engineering Department of Universidad Técnica Federico Santa María, Casilla 110-V, Av. España, 1680 Valparaíso, Chile
Abstract: Increasingly, wireless networks are being used to provide connection services for devices running applications with very different quality of service requirements. Although this issue has been addressed by the IEEE 802.11e standard, the fact is that most networks deployed in home/office environments nowadays use IEEE 802.11a/b/g standard devices. Unfortunately, administrators often do not set configuration parameters of network devices to maximize resources performance, thus providing poor quality of service. In this paper, two IEEE 802.11a/b/g analytical performance evaluation models for mixed traffic Ad Hoc and infrastructure WLANs are presented, assuming that some network devices are executing single applications, like VoIP, videoIP or network browsing. In our analysis, network devices are grouped according to the expected traffic pattern of the applications they are running. Then, global and individual group goodput are calculated assuming a congested network. Based upon the outcome of this analysis for different settings of the device configuration parameters, it is shown that the performance of a standard home/office IEEE 802.11 wireless network can be significantly improved by choosing appropriate values of these parameters.
Keywords: Wireless networks .Wi-Fi . Quality of service . Goodput
Distributed energy efficiency in future home environments
Helmut Hlavacs1· Roman Weidlich1 · Karin A. Hummel1 · Amine M. Houyou2 · Andreas Berl2 · Hermann de Meer2
1 Department of Distributed and Multimedia Systems, University of Vienna, Lenaug. 2/8, 1080 Vienna, Austria
2 Faculty of Computer Science and Mathematics, University of Passau, Innstr. 43, 94032 Passau, Germany
Abstract: In this paper, a new architecture for sharing resources among home environments is proposed. Our approach goes far beyond traditional systems for distributed virtualization, like PlanetLab or grid computing, as it relies on complete decentralization in a peer-to-peer (P2P) like manner and, above all, aims at energy efficiency. Energy metrics are defined, which have to be optimized by the system. The system itself uses virtualization to transparently move tasks from one home to another to optimally utilize the existing computing power. We present an overview of our proposed architecture, consisting of a middleware interconnecting computers and routers in possibly millions of homes using P2P techniques. For demonstrating the potential energy saving of distributed applications, we present an analytical model for sharing downloads, which is verified by discrete event simulation. The model represents an optimistic case without P2P overhead and fairness. The model allows to assess the upper limit of the saving potential. An enhanced version of the simulation model also shows the effect of fairness. The fairer the system gets, the less efficient it is.
Keywords: Energy efficiency · Home networks · Peer-to-peer · Modeling · Simulation
Looking for network functionalities' extension by avoiding energy-compromised hotspots in wireless sensor networks
J. Rahmé1 · A. Carneiro Viana2 · K. Al Agha1
1LRI, Université Paris-SUD XI, Paris, France
2 ASAP/INRIA Saclay, Ile de France sud, France
Abstract: The vast literature on the wireless sensor research community contains many valuable proposals for managing energy consumption, the most important factor that determines sensors' lifetime. Interesting researches have been facing this requirement by focusing on the extension of the entire network lifetime: either by switching between node states (active, sleep) or by using energy-efficient routing. We argue that a better extension of the network lifetime can be obtained if an efficient combination of management mechanisms can be performed at the energy of each single sensor and at the load distribution over the network. Considering these two accuracy levels (i.e., node and network), this paper presents a new approach that uses cost functions to choose energy-efficient routes. In particular, by making different energy considerations at a node level, our approach distributes routing load, avoiding, thus, energy-compromised hotspots that may cause network disconnections. The proposed cost functions have completely decentralized and adaptive behavior and take into consideration the end-to-end energy consumption, the remaining energy of nodes, and the number of transmissions a node can make before its energy depletion. Our simulation results show that, though slightly increasing path lengths from sensor to sink nodes, some proposed cost functions (1) improve significantly the network lifetime for different neighborhood density degrees, while (2) preserving network connectivity for a longer period of time.
Keywords: Static wireless sensor networks · Load distribution · Energy management
Home networking at 60 GHz: challenges and research issues
Zulkuf Genc, Bao Linh Dang, Jing Wang, Ignas Niemegeers
Wireless and Mobile Communications (WMC) Group, Faculty of Electrical Engineering, Mathematics, and Computer Science (EEMCS) of Delft University of Technology, P.O. Box 5031, 2600 GA Delft, The Netherlands
Abstract: The recent developments in CMOS technology are about opening a new exciting door to affordable 60- GHz radio applications. One promising application area for 60-GHz radio is home networks in which there is an increasing demand for multi-gigabit wireless networking. The research efforts so far have generally focused on utilizing the 60-GHz band for point-to-point communication by addressing its physical aspects like propagation characteristics and channel models. The issues of 60-GHz networking at the system level have not been adequately considered. In this paper, the challenges and the research issues of 60-GHz networking are reviewed from the system-level perspective. We present them in the context of wireless local area networks for future home networks with discussions on some possible solutions for the introduced challenges.
Keywords: Home networking . 60 GHz . Future home networks .Wireless
Max-min fair survivable networks
A. Bashllari1 · D. Nace1 · E. Gourdin2 · O. Klopfenstein2
1 Laboratoire Heudiasyc UMR CNRS 6599, Université de Technologie de Compiègne, 60205 Compiègne Cedex, France
2 France Telecom R&D, 38-40 rue du Général-Leclerc, 92794 Issy-les-Moulineaux Cedex 9, France
Abstract: In this paper, we discuss applications of max- min fairness (MMF) in survivable networks. We focus on two specific applications intended to face failure situations and provide several computational results for each of them. The first application, called simple robust routing, generalizes the multipath routing in order to achieve acceptable levels of traffic demand satisfaction in case of single link failures while avoiding classical rerouting procedures. Such a method can be seen as a special case of dedicated resource recovery schemes. The second application is concerned with two shared resource restoration strategies and the corresponding problems of computing the MMF minimum traffic demand satisfaction ratio vectors associated with the set of single link failures. We consider the local rerouting and end-to-end rerouting without stub-release strategies. Computational results for realistic network instances provide a comparison of different routing and rerouting strategies in terms of traffic satisfaction rate. The question of estimating the bandwidth overhead, which can be required by the "simple robust routing scheme" in comparison with the classical restoration schemes, is also studied and answers based on computational results are provided.
Keywords: Max-min fairness · Recovery mechanisms · Routing · Linear programming · Path generation · Survivable networks
Flow control in distributed gateways
Sutthisak Inthawadee, Dobri Atanassov Batovski
Department of Telecommunications Science, Faculty of Science and Technology, Assumption University, Ram Khamhaeng Soi 24, Hua Mak, Bangkok 10240, Thailand
Abstract: The resultant traffic flows in a preferred direction within a set of cooperative gateway nodes is optimized taking into consideration the internal rate-delay products. The internal rates on directed links among adjacent gateway nodes are included in the set of control variables. It is also shown that the optimal internal rate-delay product of a set of connected gateway nodes can be obtained by locally optimizing in each node the rates of either the input ports or the output ports. The effectiveness of the proposed optimization algorithm is demonstrated for a typical sample gateway of three nodes with inhomogeneous arrival and service rates.
Keywords: Flow control . Poisson processes . Networks
SERP: secure energy-efficient routing protocol for densely deployed wireless sensor networks
Al-Sakib Khan Pathan, Choong Seon Hong
Networking Laboratory, Department of Computer Engineering, Kyung Hee University, 1 Seocheon, Giheung, Yongin 449-701, South Korea
Abstract: In this paper, we present secure energy-efficient routing protocol (SERP) for densely deployed wireless sensor networks which aims to achieve robust security for transmitted sensor readings with an energy-efficient network backbone. When the sensors with limited energy budgets are deployed in hazardous environment, ensuring energy efficiency and security of the sensor readings becomes a crucial task. Here, we address how to deal with such a deployment scenario. Our protocol ensures secure transmission of data from the source sensors to the base station in a way that it can best utilize the available amount of energy in the network. We use one-way hash chain and pre-stored shared secret keys for ensuring data transmission security. In SERP, first, a sink rooted tree structure is created as the backbone of the network. This energyefficient network structure is used for authenticated and encrypted data delivery from the source sensors to the base station. To introduce data freshness, SERP includes an optional key refreshment mechanism which could be applied depending on the application at hand. Our analysis and simulation results show that SERP provides a good level of confidentiality and authenticity of data that are transmitted from the sensors to the base station. It also helps for energy-efficient structuring of the network so that the maximum lifetime of the network could be achieved.
Keywords: Energy . Distance . One-way hash chain . Shared secret key