Comparative Performance Evaluation of Scatternet Formation Protocols for Networks of Bluetooth Devices

This paper describes the results of the first ns2-based comparative performance evaluation among four major solutions presented in the literature for forming multi-hop networks of Bluetooth devices (scatternet formation). The four protocols considered in this paper are BlueTrees [1], BlueStars [2], BlueNet [3] and the protocol presented in [4] which proposes geometric techniques for topology reduction combined with cluster-based scatternet formation. We implemented the operations of the four protocols from device discovery to scatternet formation. By means of a thorough performance evaluation we have identified protocol parameters and Bluetooth technology features that affect the duration of the formation process and the properties of the produced scatternet. We have investigated how possible modifications of the BT technology (e.g., backoff duration, possibility for a BT inquirer to identify itself) make device discovery more efficient for scatternet formation in multi-hop networks. We have then discussed implementation concerns for each of the selected protocols. Finally, we have analyzed the protocols overhead as well as the effect of the different protocols operations on key metrics of the generated scatternets, which includes the time needed for forming a scatternet, the number of its piconets, the number of slaves per piconet, the number of roles assumed by each node and the scatternet route lengths.     

A New Bluetooth Scatternet Formation Protocol

A Bluetooth ad hoc network can be formed by interconnecting piconets into scatternets. The constraints and properties of Bluetooth scatternets present special challenges in forming an ad hoc network efficiently. In this paper, we present and analyze a new randomized distributed protocol for Bluetooth scatternet formation. We prove that our protocol achieves O(logn) time complexity and O(n) message complexity. The scatternets formed by our protocol have the following properties: (1) any device is a member of at most two piconets, and (2) the number of piconets is close to be optimal. These properties can help prevent overloading of any single device and lead to low interference between piconets. We validate the theoretical results by simulations, which also show that the scatternets formed have O(logn) diameter. As an essential part of the scatternet formation protocol, we study the problem of device discovery: establishing multiple connections simultaneously with many Bluetooth devices. We investigate the collision rate and time requirement of the inquiry and page processes. Our simulation results indicate that the total number of packets sent is O(n) and that the maximum number of packets sent by any single device is O(logn).     

A Location-Aware Routing Protocol for the Bluetooth Scatternet

Bluetooth is a most promising technology for the wireless personal area networks and its specification describes how to build a piconet. Though the construction of scatternet from the piconets is left out in the specification, some of the existing solutions discuss the scatternet formation issues and routing schemes. Routing in a scatternet, that has more number of hops and relay nodes increases the difficulties of scheduling and consumes the bandwidth and power resources and thereby impacts on the performance of the entire network. In this paper, a novel routing protocol (LARP) for the Bluetooth scatternet is proposed, which reduces the hop counts between the source and the destination and reconstructs the routes dynamically using the location information of the Bluetooth devices. Besides, a hybrid location-aware routing protocol (HLARP) is proposed to construct the shortest routes among the devices with or without having the location information and degenerate the routing schemes without having any location information. Experimental results show that our protocols are efficient enough to construct the shortest routing paths and to minimize the transmission delay, bandwidth and power consumption as compared to the other protocols that we have considered. Chih-Yung Chang received the Ph.D. degree in Computer Science and Information Engineering from National Central University, Taiwan, in 1995. He joined the faculty of the Department of Computer and Information Science at Aletheia University, Taiwan, as an Assistant Professor in 1997. He was the Chair of the Department of Computer and Information Science, Aletheia University, from August 2000 to July 2002. He is currently an Associate Professor of Department of Computer Science and Information Engineering at Tamkang University, Taiwan. Dr. Chang served as an Associate Guest Editor of Journal of Internet Technology (JIT, 2004), Journal of Mobile Multimedia (JMM, 2005), and a member of Editorial Board of Tamsui Oxford Journal of Mathematical Sciences (2001--2005). He was an Area Chair of IEEE AINA'2005, Vice Chair of IEEE WisCom 2005 and EUC 2005, Track Chair (Learning Technology in Education Track) of IEEE ITRE'2005, Program Co-Chair of MNSA'2005, Workshop Co-Chair of INA'2005, MSEAT'2003, MSEAT'2004, Publication Chair of MSEAT'2005, and the Program Committee Member of USW'2005, WASN'2005, and the 11th Mobile Computing Workshop. Dr. Chang is a member of the IEEE Computer Society, Communication Society and IEICE society. His current research interests include wireless sensor networks, mobile learning, Bluetooth radio systems, Ad Hoc wireless networks, and mobile computing. Prasan Kumar Sahoo got his Master degree in Mathematics from Utkal University, India. He did his M.Tech. degree in Computer Science from Indian Institute of Technology (IIT), Kharagpur, India and received his Ph.D in Mathematics from Utkal University, India in April, 2002. He joined in the Software Research Center, National Central University, Taiwan and currently working as an Assistant Professor, in the department of Information Management, Vanung University, Taiwan, since 2003. He was the Program Committee Member of MSEAT'2004, MSEAT'2005, WASA'2006, and IEEE AHUC'2006. His research interests include the coverage problems, modeling and performance analysis of wireless sensor network and Bluetooth technology. Shih-Chieh Lee received the B.S. degree in Computer Science and Information Engineering from Tamkang University, Taiwan, in 1997. Since 2003 he has been a Ph.D. Students in Department of Computer Science and Information Engineering, Tamkang University. His research interests are wireless sensor networks, Ad Hoc wireless networks, and mobile/wireless computing.     

蓝牙散射网的构成机制

首先介绍了蓝牙技术的相关知识,然后在此基础上重点讨论了蓝牙散射网的构成机制,最后介绍了散射网的常见结构及性能比较。     

Bluegon: a polygon-shaped scatternet formation algorithm for Bluetooth

Bluetooth is one of the cable-replacement technologies. It uses short-range radio links to replace connecting cables. Bluetooth enables portable devices to form short-range wireless ad hoc networks. A set of Bluetooth devices sharing a common channel can form a personal area network called a piconet. Several piconets can also be interconnected to establish a scatternet. Zaruba, Basaghi and Chlamtac proposed a mechanism for forming a distributed scatternet called the Bluetree. The algorithm is based on selecting an arbitrary node serving as the Blueroot. The Blueroot initiates the construction of the Bluetree. Though the algorithm is very simple, there are some weak points. For example, being a tree limits its routing choices. There are also the problems of overloading on the Blueroot and the many master/slave bridges on any routing path. In this paper, we will improve the weaknesses of Bluetree by eliminating the bottleneck in the Blueroot and by reducing the number of bridges to half for almost any path. We call the new algorithm Bluegon since polygons (cycles) will be formed in the scatternet. Simulation results indicate the efficiencies of our algorithm. Copyright © 2006 John Wiley & Sons, Ltd.     

Analytical Models for Single-Hop and Multi-Hop Ad Hoc Networks

There is considerable interest in modeling the performance of ad hoc networks analytically. This paper presents approximate analytical models for the throughput performance of single-hop and multi-hop ad hoc networks. The inherent complexity of analysis of a multi-hop ad hoc network together with the fact that the behavior of a node is dependent not only on its neighbors' behavior, but also on the behavior of other unseen nodes makes multi-hop network analysis extremely difficult. However, our approach in this paper to analyze multi-hop networks offers an accurate approximation with moderate complexity. Our approach is based on characterizing the behavior of a node by its state and the state of the channel it sees. This approach is used to carry out an analysis of single-hop and multi-hop ad hoc networks in which different nodes may have different traffic loads. In order to validate the model, it is applied to IEEE 802.11-based networks, and it is shown through extensive simulations that the model is very accurate. Farshid Alizadeh-Shabdiz received his B.Sc. in 1989 at University of Science and Technology, M.Sc. in 1991 at Tehran University, Iran, and D.Sc. in 2004 at the George Washington University. He is a senior research engineer in Advanced Solution Group, part of Cross Country Automotive Services, and he is also a part time faculty member at Boston University. Dr. Alizadeh-Shabdiz was part of the design and implementation team of the three first satellite-based mobile networks: ICO global medium orbit satellite network voice and data services, Thuraya GEO satellite network, and the first phase of Inmarsat high speed data network. His research interests include MAC layer, physical layer and network layer of wireless and satellite networks. Suresh Subramaniam received the Ph.D. degree in electrical engineering from the University of Washington, Seattle, in 1997. He is an Associate Professor in the Department of Electrical and Computer Engineering at the George Washington University, Washington, DC. His research interests are in the architectural, algorithmic, and performance aspects of communication networks, with particular emphasis on optical and wireless ad hoc networks. Dr. Subramaniam is a co-editor of the books “Optical WDM Networks – Principles and Practice” and “Emerging Optical Network Technologies: Architectures, Protocols, and Performance”. He has been on the program committees of several conferences including Infocom, ICC, Globecom, and Broadnets, and served as TPC Co-Chair for the 2004 Broadband Optical Networking Symposium. He currently serves on the editorial boards of Journal of Communications and Networks and IEEE Communications Surveys and Tutorials. He is a co-recipient of the Best Paper Award at the 1997 SPIE Conference on All-Optical Communication Systems.     

Smart-Aloha for Multi-Hop Wireless Networks

This paper presents a novel slotted ALOHA-based protocol for use in ad hoc networks where nodes are equipped with adaptive array smart antennas. The protocol relies on the ability of the antenna and DoA (Direction of Arrival) algorithms to identify the direction of transmitters and then beamform appropriately to maximize SINR (Signal to Interference and Noise Ratio) at the receiver. The performance of the protocol is evaluated using analytical modeling as well as detailed simulation in OPNET and Matlab where we demonstrate the benefits of using smart antennas. The impact of using different number of antenna elements is also studied for this environment.This work is funded by the NSF under grant ANIR-0125728.Harkirat Singh is a PhD candidate in Computer Science at Portland State University. He holds Master in Computer Science from Portland State University and B. E. in Electrical Engineering from Indian Institute of Technology (IIT), Roorkee, India. After his under graduation he joined Automation division of Siemens AG. He has research interests in next-generation TCP/IP networking, Mobile Wireless Computing, Ad-hoc networking, and low-power lost-cost sensor networks.Suresh Singh received his B. Tech. Degree in Computer Science from the Indian Institute of Technology (IIT) Kanpur in 1984 and his Ph.D. degree in 1990 from the University of Massachusetts at Amherst, both in Computer Science. His areas of research include energy-efficient protocols for wireless networking, sensor networks, cellular networking with a focus on 3g standards, and performance evaluation. His work has been funded by several federal agencies such as NSF, DARPA, and ONR and by a variety of industries. He is a member of the ACM and IEEE.     

Blue pleiades,a new solution for device discovery and scatternet formation in multi-hop Bluetooth networks

In this paper we introduce a novel and unified approach to the problems of device discovery and scatternet formation for the Bluetooth standard. We introduce a stochastic model for Bluetooth device discovery and prove that a protocol based on very simple local rules generates a topology that, with high probability, is connected and, crucially, has constant maximum degree. Based on this, we develop a new protocol for device discovery and scatternet formation for multi-hop BlueTooth networks. By means of extensive ns2 simulations we show that our solution is simple to implement, fast and requires low overhead, both for the device discovery and the scatternet formation phases, and leads to better performance when compared to the major approaches so far proposed in the literature.     

Flooding for Reliable Multicast in Multi-Hop Ad Hoc Networks

Ad hoc networks are gaining popularity as a result of advances in smaller, more versatile and powerful mobile computing devices. The distinguishing feature of these networks is the universal mobility of all hosts. This requires re-engineering of basic network services including reliable multicast communication. This paper considers the special case of highly mobile fast-moving ad hoc networks and argues that, for such networks, traditional multicast approaches are not appropriate. Flooding is suggested as a possible alternative for reliable multicast and simulation results are used to illustrate its effects. The experimental results also demonstrate a rather interesting outcome that even flooding is insufficient for reliable multicast in ad hoc networks when mobility is very high. Some alternative, more persistent variations of flooding are sketched out.     

链形结构的蓝牙分散网拓扑构成算法与性能仿真

提出了一种新的链形结构的蓝牙分散网拓扑构成算法：所有蓝牙节点均以0．5的概率进入查询或查询扫描状态，同时地进行点对点的连接，形成尽可能多的临时皮网，再反复通过各种形式的合并与重组形成更大的皮网与多个皮网形成的组，直至最终形成仅有一个组的链形结构的分散网。仿真与性能分析表明：该算法实现简单，形成的分散网具有较少的皮网数目、较小的各节点角色的平均数与较小的节点最大度数、网络创建时间较短、拓扑动态维护方便、各节点无需均在通信范围内等优点。该算法适用于蓝牙分散网的拓扑构成。     

DDBNF：一个分布式的动态蓝牙网络形成算法

提出了一个分布式的、支持节点移动性的蓝牙匹克网构造算法DDBNF,它可以有效地将随机分布在某个区域内的n个节点划分为若干个匹克网.该算法只需获得每个节点的本地拓扑信息(一跳邻居节点),基于权值大小选举主节点,允许每个普通从节点直接访问至少一个主节点,保证了每个节点对之间快速的匹克网间以及匹克网内通信.     

A Novel Scatternet Scheme with IPv6 Compatibility

Some market analysts predict that there will be some 1.4 billion Bluetooth devices in operation by the year 2005 [8]. However, the current specification1.1 does not describe the algorithms or mechanisms to create a scatternet due to a variety of unsolved issues [3,12]. Since the upper layers are not defined in Bluetooth, it is not possible to implement the scatternet in current specification. Hence in this research, we need make some modifications to Bluetooth protocol in order to support the transmissions of packets in the scatternet. In this paper we describe a novel scatternet architecture, and present link performance of the proposed architecture. The issues of the routing algorithm, handoffs, and communications with other networks are also discussed.     

A Fair and Traffic Dependent Scheduling Algorithm for Bluetooth Scatternets

The Bluetooth specification defines the notion of interconnected piconets, called scatternets, but does not define the actual mechanisms and algorithms necessary to set up and maintain them. The operation of a scatternet requires some Bluetooth units to be inter-piconet units (gateways), which need to time-division multiplex their presence among their piconets. This requires a scatternet-scheduling algorithm that can schedule the presence of these units in an efficient manner. In this paper, we propose a distributed scatternet-scheduling scheme that is implemented using the HOLD mode of Bluetooth and adapts to non-uniform and changing traffic. Another attribute of the scheme is that it results in fair allocation of bandwidth to each Bluetooth unit. This scheme provides an integrated solution for both intra- and inter-piconet scheduling, i.e., for polling of slaves and scheduling of gateways.     

Ad hoc networking with Bluetooth: key metrics and distributed protocols for scatternet formation

Bluetooth is a promising technology for personal/local area wireless communications. A Bluetooth scatternet is composed of simple overlapping piconets, each with a low number of devices sharing the same radio channel. A scatternet may have different topological configurations, depending on the number of composing piconets, the role of the devices involved and the configuration of the links. This paper discusses the scatternet formation issue by analyzing topological characteristics of the scatternet formed. A matrix-based representation of the network topology is used to define metrics that are applied to evaluate the key cost parameters and the scatternet performance. Numerical examples are presented and discussed, highlighting the impact of metric selection on scatternet performance. Then, a distributed algorithm for scatternet topology optimization is introduced, that supports the formation of a “locally optimal” scatternet based on a selected metric. Numerical results obtained by adopting this distributed approach to “optimize” the network topology are shown to be close to the global optimum.     

Evaluating Bluetooth Performance as the Support for Context-Aware Applications

We present an experiment relative to the use of the Bluetooth wireless technology to provide network support for context-aware applications. We describe an approach to provide network interconnection using a combination of wireless and wired network technologies. We also describe the steps taken to create a Bluetooth based context-aware application. We, finally, evaluate, using a small test-bed and simulation the overall performance of this technology when adopted in the area of context-aware and ubiquitous computing.     

Channel Adaptive Shortest Path Routing for Ad Hoc Networks

1　IntroductionAdhocnetworksareformedwithoutrequiringthepreexistinginfrastructureorcentralizedadminis tration ,incontrasttocellularnetworks.Asidefromtheoriginalmilitaryapplication ,ithasapplicationinpublicsafetyandcommercialareas,butadaptiveprotocolsarerequiredinorderforthemtodoso .Twoimportantcharacteristicsofacommunicationlinkinadhocnetworksareitsunreliabilityanditsvariability .Thelinksinsuchanetworkareunreli ablebecauseoffading ,interference,noise,andper hapsthefailureofthetransmittingorrec…     

ABRP: Anchor-based Routing Protocol for Mobile Ad Hoc Networks

Ad hoc networks, which do not rely on any infrastructure such as access points or base stations, can be deployed rapidly and inexpensively even in situations with geographical or time constraints. Ad hoc networks are attractive in both military and disaster situations and also in commercial uses like sensor networks or conferencing. In ad hoc networks, each node acts both as a router and as a host. The topology of an ad hoc network may change dynamically, which makes it difficult to design an efficient routing protocol. As more and more wireless devices connect to the network, it is important to design a scalable routing protocol for ad hoc networks. In this paper, we present Anchor-based Routing Protocol (ABRP), a scalable routing protocol for ad hoc networks. It is a hybrid routing protocol, which combines the table-based routing strategy with the geographic routing strategy. However, GPS (Global Positioning System) (Kaplan, Understanding GPS principles and Applications, Boston: Artech House publishers, 1996) support is not needed. ABRP consists of a location-based clustering protocol, an intra-cell routing protocol and an inter-cell routing protocol. The location-based clustering protocol divides the network region into different cells. The intra-cell routing protocol routes packets within one cell. The inter-cell routing protocol is used to route packets between nodes in different cells. The combination of intra-cell and inter-cell routing protocol makes ABRP highly scalable, since each node needs to only maintain routes within a cell. The inter-cell routing protocol establishes multiple routes between different cells, which makes ABRP reliable and efficient. We evaluate the performance of ABRP using ns2 simulator. We simulated different size of networks from 200 nodes to 1600 nodes. Simulation results show that ABRP is efficient and scales well to large networks. ABRP combines the advantages of multi-path routing strategy and geographic routing strategy—efficiency and scalability, and avoids the burden—GPS support.     

Extending Global IP Connectivity for Ad Hoc Networks

Ad hoc networks have thus far been regarded as stand-alone networks without assumed connectivity to wired IP networks and the Internet. With wireless broadband communications and portable devices with appropriate CPU, memory and battery performance, ad hoc connectivity will become more feasible and demand for global connectivity through ad hoc networking is likely to rapidly grow. In this paper we propose an algorithm and describe a developed prototype for connectivity between an ad hoc network running the ad hoc on-demand distance-vector protocol and a wired IP network where mobile IP is used for mobility management. Implementation issues and performance metrics are also discussed.     

A Location Aware Mobility based Routing Protocol for the Bluetooth Scatternet

Bluetooth is a most promising technology designed for the wireless personal area networks for the cable replacement. In this paper, a location aware mobility based routing scheme for the Bluetooth scatternet is proposed that constructs the links dynamically. Our proposed routing protocol requires location information of the nodes and constructs the route between any source and destination and reduces the number of hops. Besides, the network routing problems are analyzed and role switch operations are proposed to mitigate the problems. Moreover, the roles switch and route optimization operations are also proposed to improve route performance. Rigorous simulation works are done to evaluate the performance of our protocol in terms of mobility speed and number of mobile nodes and to compare our results with similar Bluetooth routing protocols. It is observed that our protocol outperforms in terms of energy consumption and transmission packet overheads as compared to similar Bluetooth routing protocols.

An End-to-End Bandwidth Allocation Algorithm for Ad Hoc Networks

Bandwidth-guaranteed QoS service in ad hoc networks is a challenging task due to several factors such as the absence of the central control, the dynamic network topology, the hidden terminal problem and the multihop routing property. An end-to-end bandwidth allocation algorithm was proposed in [Lin and Liu, 15] to support the QoS service in ad hoc networks. However, without exploring the global resource information along the route, the performance of that algorithm is quite limited. In addition, it also incurs significant control overhead. We develop a new algorithm for end-to-end bandwidth calculation and assignment in ad hoc networks which utilizes the global resource information along the route to determine the available end-to-end bandwidth. Our method also employs the topology-transparent scheduling technology to reduce the control overhead. The proposed algorithm can be efficiently utilized in a distributed manner. Both theoretical analysis and simulation results show that our end-to-end bandwidth allocation scheme can significantly improve the network capacity compared with the existing method.