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.     

三种无线通信协议综述

蓝牙（IEEE 802.15.1）、ZigBee（IEEE802.15.4）、Wi-Fi（IEEE 802.11）是当前流行的三种短距离无线通信协议标准,从应用的角度来看蓝牙技术是为取代个人的电子设备间的有线连接。ZigBee技术是为了建立一个可靠的无线监控网络,Wi-Fi技术的目的取代个人电脑的网线。现将对这三种流行的通信协议的主要特征比较,包括传输速度、功耗、安全。     

适用于移动云计算的抗中间人攻击的SSP方案

低功率蓝牙（BLE）专为资源受限的设备设计,但现有的研究已经指出其安全简单配对方案（SSP）存在中间人攻击（MITM）漏洞.文章指出造成MITM漏洞的根本原因是：配对信息被篡改以及JW模式自身的漏洞.为此文章中提出了两个适用于移动云计算（MCC）中BLE设备的SSP改进方案,所提出的方案基于哈希函数并利用MCC技术提高SSP的安全性.方案1适用于支持PE或者OOB模式的BLE设备,其利用哈希函数确保配对信息的真实性、可靠性.方案2通过哈希序列来解决仅支持JW模式的BLE设备的MITM攻击漏洞.文章分别从安全角度和性能角度对所提出的方案进行分析,以表明方案在不同级别敌手的攻击下可以提供MITM攻击防护能力.     

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。     

Bluetooth and Wi-Fi wireless protocols: a survey and a comparison

Bluetooth and IEEE 802.11 (Wi-Fi) are two communication protocol standards that define a physical layer and a MAC layer for wireless communications within a short range (from a few meters up to 100 m) with low power consumption (from less than 1 mW up to 100 mW). Bluetooth is oriented to connecting close devices, serving as a substitute for cables, while Wi-Fi is oriented toward computer-to-computer connections, as an extension of or substitution for cabled LANs. In this article we offer an overview of these popular wireless communication standards, comparing their main features and behaviors in terms of various metrics, including capacity, network topology, security, quality of service support, and power consumption.     

蓝牙接入设备的设计与实现

基于短距离无线通信问题的研究.为了使无线网络设备及有线网络之间能够方便有效地进行信息交换,利用新华龙公司的80C51F120芯片和蓝牙模块芯片BCM-05,文章设计一个蓝牙接入设备,使其能与各种现场设备进行数据通信.该设计的实现对家庭自动化,智能大厦及楼宇控制,办公室间通讯及计算机终端接口等实现通信具有一定应用价值.     

A Testbed for Energy Profile Characterization of IP Services in Smartphones over Live Networks

Mobile phones are becoming pervasively used to access Internet and multimedia contents due to their increasing processing power and its wide range of featured wireless communication technologies (Infrared, Bluetooth, NFC, GSM, UMTS, HSPA, WiMax, LTE). In this paper we also introduce mobile devices as a pervasive testbed platform to characterize the energy consumption profile of Internet services. The most innovative advantage provided by our solution is the testbed’s flexibility and simplicity, making it possible to carry out extensive testing campaigns using actual mobile devices in live networks with real services.     

Bluetooth协议模型及应用

Bluetooth是一种短距离范围内的无线数据和语音通信的开放性全球规范,目的是取代现有的PC、打印机、传真机和移动电话等设备上的有线接口。较详细介绍了Bluetooth的协议体系和应用模型。     

An enhanced and energy efficient communication architecture for Bluetooth wireless PANs

Bluetooth is a radio technology for Wireless Personal Area Networking (WPAN) operating in the 2.4 GHz ISM frequency band, and allows devices to be connected into short-range ad hoc networks. The Bluetooth medium access control protocol is based on the Master/Slave paradigm wherein any communication between slave devices has to go through the Master. While this model provides for simplicity, it incurs a longer delay between any two slave devices due to far from optimal packet forwarding, the use of double the bandwidth, and also additional energy wastage at the Master. Moreover, if more than two devices want to communicate as a group, this can only be achieved by either multiple unicast transmissions or a piconet-wide broadcast, clearly resulting in inefficiency. In this paper, we propose a novel Dynamic Slot Assignment (DSA) scheme whereby the Master device dynamically assigns slots to Slaves so as to allow them to communicate directly with each other without any Master intervention. This proposed communication architecture also provides for Quality of Service (QoS) requests, admission control, and multi-device conversation by which a multicast-like communication is implemented within a piconet. Through extensive simulation, we observe that DSA drastically enhances Bluetooth performance in terms of delay and throughput, while significantly reducing power consumption at the master and the overall piconet.     

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。     

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.     

A Bluetooth scatternet-route structure for multihop ad hoc networks

Bluetooth scatternets, integrating polling, and frequency hopping spread-sprectrum in their medium access control protocol, provide a contention-free environment for Bluetooth devices to access the medium and communicate over multihop links. Currently, most available scatternet formation protocols tend to interconnect all Bluetooth devices at the initial network startup stage and maintain all Bluetooth links thereafter. Instead of this "big scatternet" approach, we propose a scatternet-route structure to combine the scatternet formation with on-demand routing, thus eliminating unnecessary link and route maintenances. To the best of our knowledge, this is the first effort to address on-demand scatternet formation with every detail. We introduce an extended ID (EID) connectionless broadcast scheme, which, compared with original Bluetooth broadcast mechanism, achieves very much shortened route discovery delay. We also propose to synchronize the piconets along each scatternet route to remove piconet switch overhead and obtain even better channel utilization. Furthermore, we present a route-based scatternet scheduling scheme to enable fair and efficient packet transmissions over scatternet routes. Network performance analysis and simulations show that scatternet routes can provide multihop wireless channels with high network utilization and extremely stable throughput, being especially useful in the transmission of large batches of packets and real time data in wireless environment.     

Secure data communication in mobile ad hoc networks

We address the problem of secure and fault-tolerant communication in the presence of adversaries across a multihop wireless network with frequently changing topology. To effectively cope with arbitrary malicious disruption of data transmissions, we propose and evaluate the secure message transmission (SMT) protocol and its alternative, the secure single-path (SSP) protocol. Among the salient features of SMT and SSP is their ability to operate solely in an end-to-end manner and without restrictive assumptions on the network trust and security associations. As a result, the protocols are applicable to a wide range of network architectures. We demonstrate that highly reliable communication can be sustained with small delay and small delay variability, even when a substantial portion of the network nodes systematically or intermittently disrupt communication. SMT and SSP robustly detect transmission failures and continuously configure their operation to avoid and tolerate data loss, and to ensure the availability of communication. This is achieved at the expense of moderate transmission and routing overhead, which can be traded off for delay. Overall, the ability of the protocols to mitigate both malicious and benign faults allows fast and reliable data transport even in highly adverse network environments.     

基于DES的蓝牙安全机制研究

蓝牙作为一种短距离无线通信技术具有诸多优势,但蓝牙在设计之初对安全性的考虑不周导致了它的应用受限。分析了蓝牙的安全机制,阐述了蓝牙在认证鉴权方面的问题和E0流加密算法存在的缺陷。DES属于分组加密算法具有很高的安全性,为蓝牙加密算法的改进提供了一个新思路。最后利用VC6.0来仿真基于蓝牙的DES算法,结果说明了其具有更高的安全性能。     

EPA蓝牙通信在矿井测控系统中的应用

由于煤矿井下通信进行以太网组网时仍然需要布线,限制了现场设备的移动和网络重组。蓝牙无线通信技术具有安全性高,抗干扰性强,组网灵活的特点,替代传统以太网组网的通信技术成为必然趋势。本论文研究的矿井测控系统,将EPA蓝牙通信模块嵌入到矿井的现场设备中,实现了煤矿产业的自动化生产。     

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。     

Development of Bluewave: A Wireless Protocol for Industrial Automation

There is a growing trend in developing the wireless machine-to-machine (M2M) communication for factory automation. Currently, most wireless protocols for infrastructureless mobile ad-hoc networks focus on the mobility issue and are mainly suitable for narrowband radio devices. The mechanisms for route update and discovery that work well for wireless mobile ad-hoc networks prove to be redundant and instead add to processing overheads in a static wireless factory setting. This paper presents the development and implementation of a new wireless routing protocol, Bluewave, that caters specifically to wireless communication between machines in a factory setting. Bluewave utilizes features of Bluetooth technology when performing the route setup. The merits of the proposed protocol, in terms of shorter initialization time and route setup time, are duly discussed. A case study illustrating the application of Bluewave to an online condition-based maintenance scenario is presented. Experimental results obtained are furnished to show the viability of Bluewave in industrial automation     

Group-based multicast and dynamic membership in wireless networks with incomplete spatial coverage

In this paper we examine the problem of group-based multicast communication in the context of mobile computing with wireless communication technology. We propose a protocol in which group members may be mobile computers and such that the group membership may change dynamically. Multicasts are delivered in the same order at all group members (totally-ordered multicast). Mobile computers are resource-poor devices that communicate with a wired network through a number of spatially limited cells defining wireless links. The spatial coverage provided by wireless links may be either complete or incomplete, which makes the overall system model both general and realistic. The proposed protocol is simple and does not require any hand-off in the wired network upon movements of group members. Moreover, there is no part of the protocol requiring that group members do not move during its execution. This feature leads to mobility assumptions that are practical because they involve only the global movement of group members, e.g., assumptions of the form “a group member does not move very fast all the time”. This revised version was published online in June 2006 with corrections to the Cover Date.     

Scalable and QoS-Aware Dynamic Slot Assignment and Piconet Partitioning to Enhance the Performance of Bluetooth Ad Hoc Networks

Bluetooth is a radio technology for Wireless Personal Area Networks in the 2.4 GHz ISM frequency band and allows short-range devices to be connected in the form of ad hoc networks. The Bluetooth medium access control protocol is based on a strict master/slave concept wherein any communication between slave devices has to go through the master. While this model is simple, the use of such a nonoptimal packet forwarding scheme incurs much longer delays between any two slave-devices as double the bandwidth is used by the master. In addition, if two or more devices want to communicate as a group, this can only be achieved by either multiple unicast transmissions or a piconet-wide broadcast from the master. To handle these issues efficiently, we propose a novel combination of Dynamic Slot Assignment (DSA) and piconet partitioning. With DSA, the piconet master dynamically assigns slots to slaves so as to allow them to communicate directly with each other without any intervention from the master. Our proposed communication architecture provides for enhanced Quality of Service (QoS), better admission control, and multidevice conversation, which make a multicast-like communication feasible within the piconet. To widen the scope of DSA, we propose a QoS-aware Enhanced DSA (EDSA) version where dynamic piconet partitioning and scatternet support are exploited by grouping devices into piconets as per their connection endpoints, enabling it to be employed over a scatternet. We have performed extensive simulations and observe that these schemes drastically enhance Bluetooth performance in terms of the delay and the throughput, while significantly reducing the network power consumption.     

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。