Distributed Construction and Maintenance of Bandwidth-Efficient Bluetooth Scatternets

Bluetooth networks can be constructed as piconets or scatternets depending on the number of nodes in the network. Although piconet construction is a well-defined process specified in Bluetooth standards, scatternet construction policies and algorithms are not well specified. Among many solution proposals for this problem, only a few of them focus on efficient usage of bandwidth in the resulting scatternets. In this paper, we propose a distributed algorithm for the scatternet construction problem, that dynamically constructs and maintains a scatternet based on estimated traffic flow rates between nodes. The algorithm is adaptive to changes and maintains a constructed scatternet for bandwidth-efficiency when nodes come and go or when traffic flow rates change. Based on simulations, the paper also presents the improvements in bandwidth-efficiency provided by the proposed algorithm

A PROTOCOL SUITE FOR WIRELESS PERSONAL AREA NETWORKS

A Wireless Personal Area Network (WPAN) is an ad hoc network that consists of devices that surround an individual or an object. Bluetooth® technology is especially suitable for formation of WPANs due to the pervasiveness of devices with Bluetooth® chipsets, its operation in the unlicensed Industrial, Scientific, Medical (ISM) frequency band, and its interference resilience. Bluetooth® technology has great potential to become the de facto standard for communication between heterogeneous devices in WPANs. The piconet, which is the basic Bluetooth® networking unit, utilizes a Master/Slave (MS) configuration that permits only a single master and up to seven active slave devices. This structure limitation prevents Bluetooth® devices from directly participating in larger Mobile Ad Hoc Networks (MANETs) and Wireless Personal Area Networks (WPANs). In order to build larger Bluetooth® topologies, called scatternets, individual piconets must be interconnected. Since each piconet has a unique frequency hopping sequence, piconet interconnections are done by allowing some nodes, called bridges, to participate in more than one piconet. These bridge nodes divide their time between piconets by switching between Frequency Hopping (FH) channels and synchronizing to the piconet\u27s master. In this dissertation we address scatternet formation, routing, and security to make Bluetooth® scatternet communication feasible. We define criteria for efficient scatternet topologies, describe characteristics of different scatternet topology models as well as compare and contrast their properties, classify existing scatternet formation approaches based on the aforementioned models, and propose a distributed scatternet formation algorithm that efficiently forms a scatternet topology and is resilient to node failures. We propose a hybrid routing algorithm, using a bridge link agnostic approach, that provides on-demand discovery of destination devices by their address or by the services that devices provide to their peers, by extending the Service Discovery Protocol (SDP) to scatternets. We also propose a link level security scheme that provides secure communication between adjacent piconet masters, within what we call an Extended Scatternet Neighborhood (ESN)

Energy-efficient bluetooth scatternet formation based on device and link characteristics

Cataloged from PDF version of article.Bluetooth is a promising ad hoc networking technology. Although construction and operation of piconets are well defined in Bluetooth specifications, there is no unique standard for scatternet formation and operation. In this thesis, we propose a distributed and energy-efficient Bluetooth Scatternet Formation algorithm based on Device and Link characteristics (SF-DeviL) that is compatible with Bluetooth specifications. SF-DeviL handles energy efficiency using classes of devices, battery levels and the received signal strengths. SF-DeviL forms scatternets with tree topologies that are robust to battery depletions, where devices are arranged in an hierarchical order in terms of battery power and traffic generation rate. SF-DeviL is dynamic in the sense that the topology is reconfigured when battery levels are depleted, thereby increasing the lifetime of the scatternet. Unlike many of the algorithms in the literature SF-DeviL is also multihop, i.e., there is no requirement for each node to be in the transmission range of all other nodes.Pamuk, CananM.S

Constructing energy efficient bluetooth scatternets for wireless sensor networks

Cataloged from PDF version of article.The improvements in the area of wireless communication and micro-sensor technology have made the deployment of thousands, even millions, of low cost and low power sensor nodes in a region of interest a reality. After deploying sensor nodes in a target region of interest, which can be inaccessible by people, people can collect useful data from the region remotely. The sensor nodes use wireless communication and can collaborate with each other. However, sensor nodes are battery powered and therefore they have limited energy and lifetime. This makes energy as the main resource problem in sensor networks. The design process for sensor networks has to consider energy constraints as the main factor to extend the lifetime of the network. The wireless technology used for communication among sensor nodes can affect the lifetime of the network, since different technologies have different energy consumption parameters. Bluetooth, being low power and low cost, is a good candidate for being the underlying wireless connectivity technology for sensor networks tailored for various applications. But in order to build a large network of Bluetooth-enabled sensor nodes, we have to first form a Bluetooth scatternet. The topology of the Bluetooth scatternet affects the routing scheme to be used over that topology to collect and route informaton from sensor nodes to a base station. And routing scheme, in turn, affects how much energy is consumed during transport of information. Therefore, it is important to build a Bluetooth scatternet wisely to reduce and balance the energy consumption, hence extend the lifetime of a sensor network. In this thesis work, we propose a new Bluetooth scatternet formation algorithm to be used in Bluetooth-based sensor networks. Our algorithm is based on first computing a shortest path tree from the base station to all sensor nodes and then solving the degree constraint problem so that the degree of each node in the network is not greater than seven (a Bluetooth constraint). We also propose a balancing algorithm over the degree constrained tree to balance the energy consumption of the nodes that are closer to the base station. The closer nodes are the nodes that will consume more energy in the network since all traffic has to be forwarded over these nodes. Our simulation results show that our proposed algorithm improves the lifetime of the network by trying to reduce the energy consumed during data transfer and also by balancing the load among the nodes.Saginbekov, SainM.S

Distributed construction and maintenance of bandwidth-efficient bluetooth scatternets

Cataloged from PDF version of article.Bluetooth is currently the mainstream technology used for short range wireless communication due to its low power and low cost properties. In order to communicate, Bluetooth enabled devices can form networks called piconets, which consist of at most eight members. To construct larger Bluetooth networks, which are called scatternets, any number of piconets can be combined. Although piconet construction process is standardized by Bluetooth Special Interest Group, scatternet construction policies and algorithms are not yet clarified. There have been many solution proposals for the scatternet construction problem each of which focuses on different aspects of it like the efficiency of the construction algorithm, ease of routing in the resulting scatternet and number of piconets that constitute it. Although various considerations came into picture, bandwidth efficiency of the resulting scatternet topology, which depends on the placement of nodes and communication demand among them, did not take much attention. In this thesis, we provide a distributed and adaptive algorithm that constructs a scatternet and based on collected traffic flow information, modifies it to minimize the overall bandwidth usage. As consequences of efficient use of available bandwidth, reduce in average latency and total energy consumption as well as increase in available bandwidth for new communication demand are also aimed. Moreover, performance of the proposed algorithm is presented, based on the evaluation criteria described.Tekkalmaz, MetinM.S

Mobile Ad hoc Networking: Imperatives and Challenges

Mobile ad hoc networks (MANETs) represent complex distributed systems that comprise wireless mobile nodes that can freely and dynamically self-organize into arbitrary and temporary, "ad-hoc" network topologies, allowing people and devices to seamlessly internetwork in areas with no pre-existing communication infrastructure, e.g., disaster recovery environments. Ad hoc networking concept is not a new one, having been around in various forms for over 20 years. Traditionally, tactical networks have been the only communication networking application that followed the ad hoc paradigm. Recently, the introduction of new technologies such as the Bluetooth, IEEE 802.11 and Hyperlan are helping enable eventual commercial MANET deployments outside the military domain. These recent evolutions have been generating a renewed and growing interest in the research and development of MANET. This paper attempts to provide a comprehensive overview of this dynamic field. It first explains the important role that mobile ad hoc networks play in the evolution of future wireless technologies. Then, it reviews the latest research activities in these areas, including a summary of MANET\u27s characteristics, capabilities, applications, and design constraints. The paper concludes by presenting a set of challenges and problems requiring further research in the future

Energy efficiency in short and wide-area IoT technologies—A survey

In the last years, the Internet of Things (IoT) has emerged as a key application context in the design and evolution of technologies in the transition toward a 5G ecosystem. More and more IoT technologies have entered the market and represent important enablers in the deployment of networks of interconnected devices. As network and spatial device densities grow, energy efficiency and consumption are becoming an important aspect in analyzing the performance and suitability of different technologies. In this framework, this survey presents an extensive review of IoT technologies, including both Low-Power Short-Area Networks (LPSANs) and Low-Power Wide-Area Networks (LPWANs), from the perspective of energy efficiency and power consumption. Existing consumption models and energy efficiency mechanisms are categorized, analyzed and discussed, in order to highlight the main trends proposed in literature and standards toward achieving energy-efficient IoT networks. Current limitations and open challenges are also discussed, aiming at highlighting new possible research directions

Distributed Topology Organization and Transmission Scheduling in Wireless Ad Hoc Networks

An ad hoc network is a set of nodes that spontaneously form a multi-hop all-wireless infrastructure without centralized administration. We study two fundamental issues arising in this setting: topology organization and transmission scheduling. In topology organization we consider a system where nodes need to coordinate their transmissions on a non-broadcast frequency hopping channel to discover each other. We devise a symmetric technique where two nodes use a randomized schedule to synchronize and connect in minimum time. This forms the basis for a topology construction protocol where a set of initially unsynchronized nodes are quickly grouped in multiple interconnected communication channels such that the resulting topology is connected subject to channel membership constraints imposed by the physical layer. In the transmission scheduling problem we consider Time Division Multiple Access (TDMA)the network operates with a schedule where at each slot transmissions can be scheduled without conflicts at the intended receivers. TDMA can provide deterministic allocations but typically relies on two restrictive assumptions: network-wide slot synchronization and global knowledge of network topology and traffic requirements. We first introduce an asynchronous TDMA communication model where slot reference for each link is provided locally by the clock of one of the node endpoints. We study the overhead introduced when nodes switch among multiple time references and propose algorithms for its minimization. We then introduce a distributed asynchronous TDMA protocol where nodes dynamically adjust the rates their adjacent links via local slot reassignments to reach a schedule that realizes a set of optimal link rates. We introduce fairness models for both links and multi-hop sessions sharing the network and devise convergent distributed algorithms for computing the optimal rates for each model. These rates are enforced by a distributed algorithm that decides the slots reassigned during each link rate adjustment. For tree topologies we introduce an algorithm that incrementally converges to the optimal schedule in finite time; for arbitrary topologies an efficient heuristic is proposed. Both topology organization and transmission scheduling protocols are implemented over Bluetooth, a technology enabling ad hoc networking applications. Through extensive simulations they demonstrate excellent performance in both static and dynamic scenarios