Bluetooth Scatternet Formation Algorithm Research Articles

Forming MS-Free and Outdegree-Limited Bluetooth Scatternets in Pessimistic Environments

This paper introduces two distributed Bluetooth scatternet formation (BSF) algorithms, called $\mathtt{BSFWAVVY(MSF)}$ and $\mathtt{BSFWAVVY(ODL)}$ . The first algorithm forms scatternets that does not contain master–slave (MS) bridges (MS-free scatternets), whereas the second algorithm forms scatternets in which each piconet has at most $k$ slaves (outdegree-limited scatternets). The motivation is that MS-freeness and outdegree limitation are the two properties that significantly improve the quality of the scatternets. However, and contrary to the existing BSF algorithms, our algorithms consider these properties under pessimistic environments modeled as arbitrary networks (i.e., no assumptions are made on the underlying network topology). We give two lower bounds that prove the asymptotic optimality of our algorithms with respect to time complexity and message complexity. We also show that the problem of forming MS-free and outdegree-limited scatternets at the same time is ${\sf{NP}}$ - ${\sf{COMPLETE}}$ . We introduce a time-efficient implementation of $\mathtt{BSFWAVVY(MSF)}$ and $\mathtt{BSFWAVVY(ODL)}$ that exploits unique characteristics of Bluetooth networks. Simulation experiments show that our algorithms have short execution time relative to major BSF algorithms and it outperforms other major algorithms with respect to various performance metrics.

Bluetooth scatternet formation from a time-efficiency perspective

The Bluetooth Scatternet Formation (BSF) problem consists of interconnecting piconets in order to form a multi-hop topology. While a large number of BSF algorithms have been proposed, only few address time as a key parameter, and when doing so, virtually none of the solutions were tested under realistic settings. In particular, the baseband and link layers of Bluetooth are highly specific and known to have crucial impacts on performance. In this paper, we revisit performance studies for a number of time-efficient BSF algorithms, focusing on BlueStars, BlueMesh, and BlueMIS. We also introduce a novel time-efficient BSF algorithm called BSF-UED (for BSF based on Unnecessary-Edges Deletion), which forms connected scatternets deterministically and limits the outdegree of nodes to 7 heuristically. The performance of the algorithm is evaluated through detailed simulation experiments that take into account the low-level specificities of Bluetooth. We show that BSF-UED compares favorably against BlueMesh while requiring only 1/3 of its execution time. Only BlueStars is faster than BSF-UED, but at the cost of a very large number of slaves per master (much more than 7), which makes it impractical in many scenarios.

Towards better understanding of the behaviour of Bluetooth networks distributed algorithms

The use of frequency hopping spread spectrum in Bluetooth significantly differentiates its networks from classical radio networks. In order to observe such differences, we studied basic algorithms, in particular neighbour discovery and message exchange algorithms. Some of the major differences are found in the procedures of device discovery and link establishment, which are studied in this paper. We focus on their impact on Bluetooth networks' distributed algorithms. We show through detailed simulation experiments that minor modifications to the Bluetooth specifications or their implementation may significantly affect the performance of well-known neighbour discovery algorithms. We then study the impact of the procedures of link establishment with the purpose of finding time-efficient implementations of communication rounds for Bluetooth networks. We study OrderedExchange and RandomExchange as both algorithms implement communication rounds in Bluetooth, but use the PAGE and PAGE SCAN states differently. Theoretical analysis shows that RandomExchange has a better time complexity, while simulation experiments show that OrderedExchange significantly outperforms RandomExchange in networks with a practical size (110 nodes and less). We use the previous results to improve the time efficiency of Bluetooth scatternet formation algorithms through the introduction of the time-efficient algorithm OrderedExchangeCMIS. We believe that the study of some other basic algorithms (such as broadcasting, spanningtree and election) will lead to a better understanding of Bluetooth networks, and as a consequence, to more efficient algorithms that fully leverage the strength of this type of network.

Black Bridge: Scatternet Formation Algorithm for Solving a New Emerging Problem

Nowadays, it has become common to equip a device with Bluetooth. As such devices become pervasive in the world; much work has been done on forming them into a network, however, almost all the Bluetooth Scatternet Formation Algorithms assume devices are homogeneous. Even the exceptional algorithms barely mentioned a little about the different characteristics of devices like computational abilities, traffic loads for special nodes like bridge nodes or super nodes, which are usually the bottleneck in the scatternet. In this paper, we treat the devices differently not only based on the hardware characteristics, but also considering other conditions like different classes, different groups and so on. We use a two-phase Scatternet Formation Algorithm here: in the first phase, construct scatternets for a specified kind of devices; in the second phase, connect these scatternets by using least other kinds of devices as bridge nodes. Finally, we give some applications to show the benefit of classification.

SF-DeviL: an algorithm for energy-efficient Bluetooth scatternet formation and maintenance

Bluetooth is a short-range ad hoc networking technology, which enables formation of inexpensive personal area networks with low power consumption. Using Bluetooth technology, a small number of closely located devices can be interconnected within a piconet. Building larger ad hoc networks is possible by interconnecting multiple piconets to form a scatternet. As the Bluetooth topology grows from isolated piconets to a scatternet, energy-efficiency becomes a critical issue since additional power is consumed for multi-hop routing. A scatternet should be formed in such a way that batteries of mobile devices are efficiently used in order to lengthen scatternet lifetime. We discuss the problem of energy-efficient topology construction and maintenance for Bluetooth scatternets. An energy-efficient, distributed Bluetooth Scatternet Formation algorithm based on Device and Link characteristics (SF-DeviL) is presented. SF-DeviL forms scatternets with tree topologies and increases battery lifetimes of devices by using device types, battery levels and received signal strengths. The topology is dynamically reconfigured in SF-DeviL so that energy efficiency is maintained during the lifetime of the scatternet. It is shown through simulations that even without performing reconfiguration the network lifetime is increased by at least 229% compared to LMS algorithm and increased by at least 10% compared to BlueMesh algorithm in heterogeneous networks.