Unified clustering and communication protocol for wireless sensor networks

In this paper we present an energy-efficient cross layer protocol for providing application specific reservations in wireless senor networks called the “Unified Clustering and Communication Protocol ” (UCCP). Our modular cross layered framework satisfies three wireless sensor network requirements, namely, the QoS requirement of heterogeneous applications, energy aware clustering and data forwarding by relay sensor nodes. Our unified design approach is motivated by providing an integrated and viable solution for self organization and end-to-end communication is wireless sensor networks. Dynamic QoS based reservation guarantees are provided using a reservation-based TDMA approach. Our novel energy-efficient clustering approach employs a multi-objective optimization technique based on OR (operations research) practices. We adopt a simple hierarchy in which relay nodes forward data messages from cluster head to the sink, thus eliminating the overheads needed to maintain a routing protocol. Simulation results demonstrate that UCCP provides an energy-efficient and scalable solution to meet the application specific QoS demands in resource constrained sensor nodes. Index Terms — wireless sensor networks, unified communication, optimization, clustering and quality of service

On the Design of Ambient Intelligent Systems in the Context of Assistive Technologies

The design of Ambient Intelligent Systems (AISs) is discussed in the context of assistive technologies. The main issues include ubiquitous communications, context awareness, natural interactions and heterogeneity, which are analyzed using some examples. A layered architecture is proposed for heterogeneous sub-systems integration with three levels of interactions that may be used as a framework to design assistive AISs.Ministerio de Ciencia y Tecnología TIC2001-1868-C0

Integration between WSNs and Internet based on Address Internetworking for Web Services

There has been an increasing interest in wireless sensor networks as a new technology to realize ubiquitous computing, and demands for internetworking technology between the wireless sensor networks and the Internet which is based on IP address. For this purpose, this paper proposes and implements the internetworking scheme which assigns IP addresses to the sensor nodes and internetworks based on the gateway-based integration for internetworking between the wireless sensor networks and the Internet. That is, the proposed scheme makes the access to the wireless sensor networks be serviced as like the Web service with internetworking Internet IP address and ZigBee address which is allocated to the sensor node in wireless sensor networks. For validating the proposed scheme, we made experiments using Berkeley TinyOS, Mica Motes, dual protocol stack based on ZigBee and IP, and showed the service result using browser (IE) and IPv6 address based on DNS

Millimeter-wave Wireless LAN and its Extension toward 5G Heterogeneous Networks

Millimeter-wave (mmw) frequency bands, especially 60 GHz unlicensed band, are considered as a promising solution for gigabit short range wireless communication systems. IEEE standard 802.11ad, also known as WiGig, is standardized for the usage of the 60 GHz unlicensed band for wireless local area networks (WLANs). By using this mmw WLAN, multi-Gbps rate can be achieved to support bandwidth-intensive multimedia applications. Exhaustive search along with beamforming (BF) is usually used to overcome 60 GHz channel propagation loss and accomplish data transmissions in such mmw WLANs. Because of its short range transmission with a high susceptibility to path blocking, multiple number of mmw access points (APs) should be used to fully cover a typical target environment for future high capacity multi-Gbps WLANs. Therefore, coordination among mmw APs is highly needed to overcome packet collisions resulting from un-coordinated exhaustive search BF and to increase the total capacity of mmw WLANs. In this paper, we firstly give the current status of mmw WLANs with our developed WiGig AP prototype. Then, we highlight the great need for coordinated transmissions among mmw APs as a key enabler for future high capacity mmw WLANs. Two different types of coordinated mmw WLAN architecture are introduced. One is the distributed antenna type architecture to realize centralized coordination, while the other is an autonomous coordination with the assistance of legacy Wi-Fi signaling. Moreover, two heterogeneous network (HetNet) architectures are also introduced to efficiently extend the coordinated mmw WLANs to be used for future 5th Generation (5G) cellular networks.Comment: 18 pages, 24 figures, accepted, invited paper

Internet Predictions

More than a dozen leading experts give their opinions on where the Internet is headed and where it will be in the next decade in terms of technology, policy, and applications. They cover topics ranging from the Internet of Things to climate change to the digital storage of the future. A summary of the articles is available in the Web extras section

Compound Wired/Wireless Internetworking with OSPF

As wireless ad hoc networks become more deployed, there is a growing interest for compound internetworks, that is, internetworks that contain both fixed and ad hoc networks. Routing is one of the main challenges that arise in such compound internetworks. Although specialized routing protocols exist for wired and for ad-hoc networks, and several such specialized protocols could be used together in a compound internetwork, it has been shown that the use of a single routing solution in the whole internetwork brings several advantages. The IETF has standardized extensions of the Open Shortest Path First (OSPF) protocol for ad hoc operation. While previous performance evaluations of these extensions have focused on the wireless part of the internetwork and have been mostly performed by way of simulation tools, this paper studies practical issues of the use of a single protocol, extended OSPF, providing paths through a compound internetwork. In first term, it examines the behavior of OSPF in a real networking testbed. This testbed consists of an internetwork composed of 6 computers that form a static topology, \emph{i.e.}, computers do not move during network lifetime. In second term, the overall behavior of extended OSPF, both considering standard OSPF and its MANET extension, is examined. Despite the limitations of the testbed, these experiments provide both a proof-of-concept and complementary results compared to prior work in the domain, which was mostly based on simulations, and focused on wireless ad hoc network scenarios only.À mesure que les réseaux ad hoc sans fil deviennent de plus en plus déployés, il y a un intérêt croissant pour des internetworks (réseaux des réseaux) hybrides, c'est-à-dire, internetworks qui contiennent à la fois des réseaux ad hoc et des réseaux fixes. En ce domain-là, le routage est un des principaux défis qui se posent. Bien qu'il existe des protocoles de routage spécifiques pour réseaux filières et des réseaux sans fils et ad hoc, et plusieurs de ces protocoles pourraient être utilisés ensemble dans un internetwork hybride, il a été montré que l'utilisation d'une seule solution de routage dans un internetwork hybride a plusieurs avantages. L'IETF a standardisé trois extensions du protocole Open Shortest Path First (OSPF) ayant pour but le routage dans des réseaux ad hoc et à mobilité (MANETs). Les évaluations du rendement de ces extensions développées jusqu'à présent se sont concentrées sur la partie sans fil (ad hoc) de l'internetwork et ont été principalement effectuées à travers de simulations. Ce rapport étudie des questions pratiques liées a l'usage d'un seul protocol de routage, en l'occurrence OSPF, sur un internetwork hybride. D'abord, la performance de OSPF est analysée avec des experiénces sur un banc d'essai de réseaux (testbed). Ce testbed consiste en un internetwork hybride de 6 ordinateurs qui forment une topologie statique, c.-à.-d. où les ordinateurs ne bougent pas durant la vie du réseau. Deuxièmement, le comportement global du protocole OSPF étendu, à la fois sa version standard et son extension pour MANETs, est examiné. Malgré les limites du testbed, ces expériences fournissent à la fois une preuve de concept et des résultats qui confirment et complétent des travaux antérieurs dans le domaine, basés sur l'analyse du protocol sur MANETs à travers des simulations