A traffic-aware scheduling for bluetooth scatternets

Bluetooth is a low cost, low power, short-range radio technology used for wireless personal area networks (PANS). Bluetooth scatternet is a set of piconets interconnected via bridge devices. Good interpiconet schedulings are necessary for bridge devices to switch among piconets they participate in. This paper proposes an interpiconet scheduling algorithm named "Traffic-Aware Scatternet Scheduling" (TASS), for bridges in Bluetooth scatternets. According to masters' traffic information, TASS can adaptively switch the bridge to high traffic load masters, and increase the usage of the bridge. In addition, TASS can reduce the number of failed "unsniffs" and the overhead of "bridge switch wastes" to further increase overall system performance. Simulation results show that TASS outperforms existing interpiconet scheduling in both network throughput and adaptability for various traffic loads.     

蓝牙技术的市场展望

蓝牙技术指建立通用的无线接口及控制软件的开放标准,使得各种便携式设备在近距离范围内实现无线的互连互通。蓝牙技术主要针对三大类的应用：话音／数据接入、外围设备互连和个人局域网。本文描述了利用蓝牙技术制造的点连接、点对多点连接的市场应用产品以及个人局域网等网络产品。文章最后还描述了蓝牙技术的市场前景,并指出蓝牙技术更适合在中国发展。     

An Analytical Study of the Delay in Bluetooth Networks Using the Personal Area Network Profile

Bluetooth is the most employed technology to develop wireless personal area networks. This letter studies the performance of Bluetooth transmissions that make use of the PAN (personal area network) profile. In particular, the study offers an analytical model that defines the optimal bound for the end-to-end data delay. The proposed 'delay budget' takes into account the overhead and segmentation provoked by the protocols involved in the transmission of user data. The model is empirically validated by comparing its results with those obtained through the measurements of actual Bluetooth connections.     

Personal Area Networks: Bluetooth or IEEE 802.11?

Interconnecting all our electronic devices we carry around, such as cellular phones, PDAs, and laptops, with wireless links requires a cheap, low-power radio technology that still delivers good performance. In this context, the Bluetooth wireless technology was developed to meet the requirements introduced by these personal area networks (PANs). However, today we see a widespread deployment of wireless local area network (WLAN) radios (primarily IEEE 802.11b) also in small devices, such as PDAs. This paper will compare the PAN capabilities of a Bluetooth-based system with an IEEE 802.11b-based system. In order to focus the comparison on link and networking functionality, the IEEE 802.11b radio is assumed to be operating at the same power level as the Bluetooth radio (i.e., assuming a 0 dBm radio). Results are obtained by means of simulations in which throughput and delay are measured for multihop and overlaid PANs. Estimations on power usage are also given in the simulations. The results indicate that as the number of PANs increases, the Bluetooth-based PANs basically maintain the same bandwidth per PAN, while the corresponding IEEE 802.11-based PANs suffer significantly from the increased co-channel interference. However, for cases with a few co-channel-interfering PANs (2-3 PANs hosting about 10-15 nodes), the IEEE 802.11b-based PANs offer a higher bandwidth per user than the corresponding Bluetooth PANs, which corresponds to the difference in link bandwidth between the two systems. At high interference levels, the Bluetooth PAN offers a higher capacity than the IEEE 802.11 PAN. The latter also shows unfairness among TCP connections in the PAN at high loads. The energy efficiency, defined as successfully transmitted bits per energy unit, decreases sharply for IEEE 802.11 with increased number of PANs, while Bluetooth maintains a constant level. Packet delays are also shown to be more stable for the Bluetooth PAN than for the IEEE 802.11 PAN as the number of PANs increases.     

Challenges of eWALL Wireless Interoperability

Due to development of different technologies there has been significant improvement in quality of life. As a result of that, average person’s lifetime duration has been increased. That triggers the problem of independent living of senior citizens. One of the main concerns of the world today is how to enable senior citizens to live independently. As a response to that, systems like eWALL are being developed. eWALL for Active Long Living is a FP7 funded project and it aims to develop system which will enable elderly people to live independently. These systems consist of a large number of sensors which make wireless sensor network. In this paper, different wireless technologies that can be used for communication in systems that are designed to support independent living of elderly people, have been described. The most important focus is at wireless personal area network technologies, like ZigBee, Bluetooth, Bluetooth Low Energy and wireless local area network technologies (e.g., Wi-Fi). There are many obstacles in designing wireless sensor network and most of them concern energy efficiency and interoperability of different technologies that are being used for communication. The main challenge in the current technology world is tremendous increase of use of various wireless devices and technologies, which can cause relatively high interference, so that the wireless devices can stop working. Using cognitive radio in solving the interoperability problem of different wireless technologies in wireless sensor networks has become interesting research topic. In this paper, research on interoperability of different wireless technologies is presented. Using Spectrum Engineering Advanced Monte Carlo Analysis Tool wireless sensors network in home environment was modelled. Interference based on devices layout and activity was investigated. Also, possible improvements that can be made with cognitive radio are investigated and obtained results are given in this paper.     

基于蓝牙技术的嵌入式网络接入点设计与实现

蓝牙技术作为一种短距离、低成本的无线通信技术标准,具有低功耗和稳定性强的特点,已广泛应用于各类手持移动设备中。本文阐述了一种将移动或固定数据终端设备通过无线蓝牙技术在短距离内实现无线接入局域网或Internet的嵌入式网络接入点(NAP)设计。     

Distributed topology construction of Bluetooth wireless personal area networks

Bluetooth, a wireless technology based on a frequency-hopping physical layer, enables portable devices to form short-range wireless ad hoc networks. Bluetooth hosts are not able to communicate unless they have previously discovered each other through synchronization of their timing and frequency-hopping patterns. Thus, even if all nodes are within proximity of each other, only those nodes which are synchronized with the transmitter can hear the transmission. To support any-to-any communication, nodes must be synchronized so that the pairs of nodes, which can communicate with each other, form a connected graph. Using Bluetooth as an example, we first provide deeper insights into the issue of link establishment in frequency-hopping wireless systems. We then introduce an asynchronous distributed protocol that begins with nodes having no knowledge of their surroundings and terminates with the formation of a connected network topology satisfying all constraints posed by Bluetooth. An attractive protocol feature is its ease in implementation using the communication primitives offered by the Bluetooth Specification.     

Energy-aware on-demand scatternet formation and routing for Bluetooth-based wireless sensor networks

Bluetooth is a promising short-range wireless communication technology with the characteristics of interference resilience and power efficiency, both desirable for wireless sensor networks. The new Intel Mote sensor devices have Bluetooth technology incorporated as the standard wireless communications interface. When using Bluetooth in applications where multihop routing is required, groups of Bluetooth piconets combine together to form a scatternet. However, most of the existing scatternet formation protocols are designed to facilitate communications between any two pairs of devices, regardless of the actual traffic demand pattern. For wireless sensor network applications with low-duty-cycle traffic patterns, an on-demand scatternet formation protocol can achieve significant power saving by avoiding unnecessary network connectivity. To that end, we introduce an on-demand scatternet and route formation protocol designed specifically for Bluetooth-based wireless sensor networks. Our protocol builds a scatternet on demand, and is able to cope with multiple sources initiating traffic simultaneously. In addition, our energy-aware forwarding nodes selection scheme is based on local information only, and results in more uniform network resource utilization and improved network lifetime. Simulation results show that our protocol can provide scatternet formation with reasonable delay and good load balance, which results in prolonged network lifetime for Bluetooth-based wireless sensor networks.     

An overview of the Bluetooth wireless technology

The Bluetooth^TM wireless technology is designed as a short-range connectivity solution for personal, portable, and handheld electronic devices. Since May 1998 the Bluetooth SIG has steered the development of the technology through the development of an open industry specification, including both protocols and application scenarios, and a qualification program designed to assure end-user value for Bluetooth products. This article highlights the Bluetooth wireless technology     

应用蓝牙技术组建无线局域网

采用蓝牙技术组建无线局域网，不仅在办公条件不完善时能发挥作用，在临时增删办公点和移动性办公业务方面也有着独特的优势。对蓝牙技术做了介绍，并就组网体系结构做了说明，对蓝牙技术的发展趋势做了展望。     

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.     

A Novel Multimedia Streaming Scheme for N-Screen Services in Wireless USB Networks

Ultra wideband (UWB) technology has emerged as a solution for the wireless interface between medical sensors and a personal server in future telemedicine systems. Wireless universal serial bus (USB) is the USB technology merged with UWB technology. Wireless USB can be applied to wireless personal area network applications as well as personal area network applications like wired USB. In case of n-screen service applications, data traffics must broadcast to the adjacent devices However, the current wireless USB is designed to support the communication through the point-to-point connection between the host and the device only. This policy increases delay and energy consumption of wireless host and devices significantly. Therefore, in this paper, we propose a novel multimedia streaming scheme for n-screen service in wireless USB networks. The simulation results show that proposed protocol can enhance the throughput and delay performance and improve energy efficiency by minimizing the multimedia data delivery process.     

SATELLITE-ENHANCED PERSONAL COMMUNICATIONS EXPERIMENTS

Users of future generation wireless information services will have diverse needs for voice, data, and potentially even video communications in a wide variety of circumstances. For users in dense, inner-city areas, low power personal communications services (PCS) technology should be ideal. Vehicular-based users travelling at high speeds will need high-power cellular technology. For users in remote or inaccessible locations, or for applications that are broadcast over a wide geographic area, a satellite technology would be the best choice. Packet data networks provide an excellent solution for users requiring occasional small messages, whereas circuit switched networks provide more economical solutions for larger messages. To provide ubiquitous personal communications service, it is necessary to capitalize on the strength of each wireless technology and network to create one seamless internetwork including both current and future wired and wireless networks. As an initial step in exploring the opportunities afforded by the merging of satellite and terrestrial networks, Bellcore and JPL conducted several experiments. These experiments utilized Bellcore's experimental personal communications system (including several messaging applications with adaptations to wireless networks), NASA's advanced communications technology satellite (ACTS), JPL's ACTS mobile terminal, and various commercial data networks (such as the wireline Internet and the RAM wireless packet data network). Looking at loss of bits, packets and higher layer blocks (over the satellite-terrestrial internetworks with mobile and stationary users under various conditions) our initial results indicate that the communication channel can vary dramatically, even within a single network. We show that these conditions necessitate powerful and adaptive protocols if we are to achieve a seamless internetworking of satellite and terrestrial networks.     

蓝牙通信及其安全体系

蓝牙通信技术作为一种短距离无线通信技术,将广泛应用于个人办公或商务环境中。蓝牙通信协议栈包括专为蓝牙通信开发的核心协议、借用继承协议。蓝牙规范通过各种应用轮廓来支持各种具体应用业务。蓝牙通信技术具有较完整的安全体系结构,能实现设备级的身份鉴别和授权,并能实现链路级的数据加密通信。但是,蓝牙通信技术在安全方面仍有值得思考的地方。     

蓝牙技术在电梯断电平层控制中的应用

蓝牙技术作为一种新的短距离无线数据通信．统,是顺应时代的发展。文中在现有电梯控制特点的基础上．绍了该套方案的硬件组成和电梯与蓝牙接入设备的通信流程。迅速应用于控制领域。将蓝牙技术应用于电梯断电平层控制系设计了一种利用蓝牙技术的电梯断电平层控制方案,详尽地介为蓝牙技术在电梯控制方面的应用提供了很大的参考价值。     

Soft real‐time communications over Bluetooth under interferences from ISM devices

Bluetooth is a suitable technology to support soft real‐time applications like multimedia streams at the personal area network level. In this paper, we analytically evaluate the worst‐case deadline failure probability of Bluetooth packets under co‐channel interference as a way to provide statistical guarantees when transmitting soft real‐time traffic using ACL links. We consider the interference from independent Bluetooth devices, as well as from other devices operating in the ISM band like 802.11b/g and Zigbee. Finally, we show as an example how to use our model to obtain some results for the transmission of a voice stream. Copyright © 2006 John Wiley & Sons, Ltd.     

短距离低功率无线通信接入系统

短距离低功率无线通信接入技术主要集中在物理层和媒体访问控制（MAC）层,包括蓝牙、超宽带（UWB）和Wi-Fi等。蓝牙是链接近距离设备的电缆数据传送的辅助技术;UWB作为窄脉冲无线电技术链接众多电子设备,提供宽带无线接入的灵活性和移动性;Wi-Fi给快速接入设备和WLAN内移动设备提供无线链接,用于较长距离链接,支持一定功率的移动终端接入。短距离低功率无线通信接入系统的标准化进程非常快,辅助标准多,但目前仍以蓝牙和Wi-Fi为主。     

蓝牙无线通信技术的应用

介绍了蓝牙无线通信技术的各种应用模式，描述了蓝牙技术在工业、信息家庭、军事上的应用及蓝牙技术的市场前景。     

Topics in integrated circuits for communications [Series Editorial]

Over the past several years, mobile personal communication devices have converged to a few popular platforms including the smart phone, personal media player, and personal navigation device. More recently, a miniature laptop known as a netbook has also become increasingly widespread. Common in all these devices is the incorporation of multiple communication functions such as personal navigation, personal area networking, local area networking, wireless personal area networking, TV reception, and mobile cellular networking. Moreover, many of these functions are provided via different communications standards; for example, the Global Positioning System (GPS) for personal navigation, IEEE 802.11a/g/n (otherwise known as Wi-Fi) for wireless local area networking, and Bluetooth and IEEE 802.15.4 (ZigBee) for wireless personal area networking. In the case of TV broadcasting, standards are well established but extremely fragmented. A short list of digital TV broadcast standards includes DVB-H, DVB-T, ISDB-T, T-DMB, CMMB, and MediaFLO. Cellular standards likewise are still fragmented based on GSM/EDGE and WCDMA/UMTS although the cellular industry is working diligently toward a consolidated fourth-generation system based on Third Generation Partnership Project (3GPP) Long Term Evolution (LTE).     

Analyzing the Secure Simple Pairing in Bluetooth v4.0

This paper analyzes the security of Bluetooth v4.0’s Secure Simple Pairing (SSP) protocol, for both the Bluetooth Basic Rate/Enhanced Data Rate (BR/EDR) and Bluetooth Low Energy (LE) operational modes. Bluetooth v4.0 is the latest version of a wireless communication standard for low-speed and low-range data transfer among devices in a human’s PAN. It allows increased network mobility among devices such as headsets, PDAs, wireless keyboards and mice. A pairing process is initiated when two devices desire to communicate, and this pairing needs to correctly authenticate devices so that a secret link key is established for secure communication. What is interesting is that device authentication relies on humans to communicate verification information between devices via a human-aided out-of-band channel. Bluetooth v4.0’s SSP protocol is designed to offer security against passive eavesdropping and man-in-the-middle (MitM) attacks. We conduct the first known detailed analysis of SSP for all its MitM-secure models. We highlight some issues related to exchange of public keys and use of the passkey in its models and discuss how to treat them properly.